Effects of growth hormone-releasing hormone and somatostatin on sleep EEG and nocturnal hormone secretion in male controls. When applied centrally to animals, growth hormone-releasing hormone (GHRH) stimulates slow-wave sleep (SWS), whereas somatostatin (SRIF) increases REM sleep. We investigated whether these peptides also affect the sleep EEG in humans when given intravenously by comparing polysomnographically the effects of four boluses of (1) placebo, (2) 50 micrograms GHRH or (3) 50 micrograms SRIF administered at 22.00, 23.00, 24.00 and 1.00 h to 7 male controls. In addition, we collected blood samples through a long catheter every 20 min from 22.00 to 7.00 h and measured plasma cortisol and growth hormone (GH) levels. In comparison with SRIF and placebo, GHRH produced a significant increase in plasma GH concentration throughout the night (mean +/- SD: 10.8 +/- 2.0 ng/ml after GHRH; 3.0 +/- 1.7 ng/ml after SRIF and 3.2 +/- 2.0 ng/ml after placebo). SRIF failed to substantially attenuate the nocturnal GH release. Nocturnal cortisol secretion was blunted after GHRH but remained unaffected by SRIF (61.4 +/- 12.9 ng/ml after placebo; 46.6 +/- 19.7 ng/ml after GHRH and 70.8 +/- 12.6 ng/ml after SRIF). Quantitative sleep EEG staging showed a significant increase in SWS after GHRH administration but no change after SRIF (percent spent in SWS per night: 14.0 +/- 5.6 after placebo, 20.2 +/- 6.6 after GHRH and 15.1 +/- 8.2 after SRIF). Application of SRIF was accompanied by a trend toward increased REM density. The effects of episodic GHRH administration upon SWS, GH and cortisol secretion were opposite to those previously reported for corticotropin-releasing hormone, which supports the view that neuroregulation of human sleep involves an interaction of central GHRH and corticotropin-releasing hormone.


Are 5-HT receptors or beta-adrenoceptors involved in idazoxan-induced food and water intake? Idazoxan (10 mg/kg, i.p.) produces an unexpected increase in food intake in freely-feeding rats which has been linked to its high affinity for non-adrenoceptor idazoxan binding sites. In this study, a dose-related antagonism of idazoxan-induced food intake by the beta-adrenoceptor antagonist (-)-propranolol (5-20 mg/kg, i.p.), which also blocks 5-HT1 (5-hydroxytryptamine1) receptors has been demonstrated. (+)-Propranolol (10, 20 mg/kg, i.p.) did not attenuate idazoxan-induced feeding. (-)-Propranolol (10 mg/kg, i.p.) but not the (+)-enantiomer (10 mg/kg, i.p.) also significantly inhibited the food intake, induced by the 5-HT1A agonist 8-OH-DPAT (0.25 mg/kg, i.p.). Idazoxan-induced feeding was not altered by the selective beta-adrenoceptor antagonists betaxolol (beta 1; 5 mg/kg, i.p.) and ICI 118,551 (beta 2; 5 mg/kg, i.p.) but was potentiated by the 5-HT receptor antagonist metergoline (5 mg/kg, i.p.). The anomalous findings with metergoline may reflect its action at different sub-types of 5-HT receptor. The water intake induced by idazoxan and the peripherally-active alpha 2-adrenoceptor antagonist L-659,066 was also blocked in a stereoselective manner by propranolol (10 mg/kg) but not significantly by either metergoline (5 mg/kg, i.p.), the beta 1-adrenoceptor antagonist betaxolol (5 mg/kg, i.p.) nor by the beta 2-adrenoceptor antagonist ICI 118,551 (5 mg/kg, i.p.). These results suggest that the food intake induced by idazoxan (and perhaps mediated by non-adrenoceptor idazoxan binding sites) may involve the 5-HT system, although further studies, using antagonists acting selectively at the different sub-types of 5-HT receptor, are required to confirm this.(ABSTRACT TRUNCATED AT 250 WORDS)


Effects of chronic treatment with ethanol and withdrawal of ethanol on levels of dopamine, 3,4-dihydroxyphenylacetic acid and homovanillic acid in the striatum of the rat. Influence of benzodiazepines, barbiturate and somatostatin. Administration of ethanol for 40 days, at 10.53 +/- 0.25 g/kg/day did not modify levels of dopamine (DA) or 3,4-dihydroxyphenylacetic acid (DOPAC) in the striatum of the rat; however, the concentration of homovanillic acid (HVA) and the ratio of turnover were increased in a statistically significant way (P < 0.05). Twenty-four hours after withdrawal of ethanol appears as the central time of the ethanol-induced abstinence syndrome, showing noticeable decreases in levels of DA (P < 0.05) and DOPAC (P < 0.05), with respect to control and chronically ethanol-treated groups. The concentrations of DA, DOPAC and HVA and ratio of turnover values showed a tendency to return to control normal levels of 48 hr after ethanol withdrawal, although the differences still showed statistical significance (P < 0.05). The intraperitoneal injection of saline, the water soluble benzodiazepine midazolam, the barbiturate thiopental and somatostatin, in single doses, resulted in a noticeable increase in levels of DA, DOPAC and HVA and ratio of turnover values. The intraperitoneal injection of midazolam produced statistically significant decreases in levels of DOPAC and ratio of turnover values (P < 0.01) in rats 48 hr after withdrawal of ethanol, with respect to control and chronically ethanol-treated animals, in contrast to the absence of changes produced when injecting thiopental or somatostatin.


Characterization of glutamate efflux from preoptic area synaptosomes. Treatment of ovariectomized rats in vivo with ovarian steroids has been found to influence the efflux of glutamate and gamma-aminobutyric acid from preoptic area synaptosomes incubated in vitro. Since these studies indicated a possible role of the glutamate carrier in steroid-modulated release of amino acids, the present studies examined the characteristics of efflux of glutamate and of the carrier system for glutamate in synaptosomes of the preoptic area derived from ovariectomized hormone-treated rats. The efflux of [3H]glutamate from preoptic area synaptosomes, was induced by glutamate and by the glutamate carrier agonist, D-aspartate; the putative glutamate carrier antagonist dihydrokainate failed to block this efflux. Dihydrokainate inhibited the uptake of glutamate but it was less effective than D-aspartate. The excitatory amino acid receptor agonists, N-methyl-D-aspartate and kainate were without effect while quisqualate modestly stimulated the efflux of [3H]glutamate. Efflux of [3H]glutamate, induced by glutamate itself or by D-aspartate was not blocked by the excitatory amino acid receptor antagonists, D-2-amino-5-phosphonovaleric acid, 6,7-dinitroquinoxaline-2,3-dione or kynurenate. Glutamate-induced efflux of [3H]glutamate did not require external Ca2+. Glutamate altered neither the basal nor the potassium-induced increases in the intrasynaptosomal concentration of Ca2+ as measured by the fura-2 method. Glutamate-induced efflux of [3H]glutamate was blocked by the putative chloride channel antagonist, 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid. It is concluded that the glutamate-induced efflux of [3H]glutamate in synaptosomes of the preoptic area is a carrier-mediated process that does not require activation of receptors.(ABSTRACT TRUNCATED AT 250 WORDS)


Pattern recognition by matched filtering: an analysis of sleep spindle and K-complex density under the influence of lormetazepam and zopiclone. The evaluation of sleep EEG patterns is mostly accomplished by visual analysis. With modern personal computers however, it is possible to perform signal detection within a reasonable length of time automatically. This paper presents a method for signal processing based on matched filtering. This allows the detection of sleep spindles and K-complexes in a sleep EEG recording with a high degree of accuracy. First the technique is described, and the results of a validation study based on the comparison of visual evaluations and computer analysis are presented. Thereafter, results of an application study are presented. Sleep spindle and K-complex density under the influence of lormetazepam and zopiclone were examined. Under both medications sleep spindle density increased while K-complex density decreased. Computation of Pearson's correlation coefficients demonstrated that the interindividual sleep spindle and K-complex variations under both treatments are highly correlated. The data suggest that lormetazepam and zopiclone, although chemically different, have a similar mode of action and display comparable effects on the sleep EEG.


Cerebrospinal-fluid neuropeptides: a biochemical subgrouping approach. Cerebrospinal-fluid (CSF) corticotropin-releasing hormone, somatostatin, and thyrotropin-releasing hormone were measured by specific radioimmunoassays in 257 hospitalized psychiatry patients suffering from dementia disorders (n = 85), schizophrenia (n = 104), and mood and anxiety disorders (n = 39). Neurological controls (n = 29) were also investigated. Since there were large overlaps of the peptide levels across the nosological groups we subjected the dataset to a three-dimensional normal mixture distribution analysis. We obtained four biochemically separable clusters. Dementia disorders, but not the others, were heterogeneously distributed in these clusters but after eliminating the effects of age and illness duration this difference disappeared. No single clinical, psychological, or background variable emerged as a prominent correlate of the neuropeptide clusters. It is concluded that although CSF neuropeptide concentrations in psychiatric patient populations appear to be separable into distinct, normally distributed subgroups this distinction does not coincide with present nosological classifications.


Effects of an oral glucose load on plasma neurotransmitters in humans: involvement of REM sleep? Plasma noradrenaline (NA), adrenaline (Ad), dopamine (DA), platelet serotonin (p5HT), free serotonin (f5HT), glucose, heart rate (HR) and blood pressure (BP) were measured before and after an oral load of glucose (OGTT) in 100 normal humans. One sham-feeding test was performed in every subject 2-3 weeks before OGTT. Aside from glucose rise, significant increases in NA, p5HT and the NA/Ad ratio were registered. No significant changes were observed in Ad, DA, f5HT, HR and BP mean +/- SE values. Significant reductions in the NA/p5HT, Ad/p5HT and DA/p5HT ratios' mean values were registered at 90 and 180 min. Several significant correlations were found amongst plasma neurotransmitters. Very high positive correlations were obtained when NA, Ad and DA were plotted against the ratio of each one of them over p5HT; however, they (r = 0.99) decreased significantly at 90 and 180 min. Upon evaluation of these results we infer that quiescence of adrenal glands occurs during OGTT. Under such circumstances, plasma neurotransmitters are left under the control of a central bipolar system: noradrenergic-parasympathetic. All numerical data strongly suggest that the noradrenergic system predominates at 60, 120 and 210 min, whereas parasympathetic predominance occurs at 90 and 180 min. The fact that the latter is interfered by atropine reinforces this hypothesis. Analyses of correlations also suggest that DA and p5HT probably act as a buffer and modulate the excessive increase in NA plasma levels registered during OGTT.


The influence of neuroleptics on specific syndromes and symptoms in schizophrenics with unfavourable long-term course. A 5-year follow-up study of 50 chronic schizophrenics. Fifty chronic schizophrenics with severe residual psychopathology were followed up over a 5-year period. All of them had continuously received neuroleptics for many years before and throughout the period of investigation. In 60% (n = 30) of the patients positive symptoms which were unchanged in quality and severity were present throughout the period of investigation. In 28% (n = 14) of the patients marked positive symptoms persisted from the very beginning up to 1990 (in every case more than 20 years). Applying Leonhard's classification it was obvious that syndromes are roughly unchanged with respect to the preneuroleptic era. In these patients neuroleptics seemed to have only unspecific suppressing effects on affectivity. It is supposed that in schizophrenia which leads to severe residual psychopathology, Leonhard's classification is superior to the positive-negative distinction and is a promising concept for future research in etiology and therapy.


Quantitative EEG and autonomic patterns of synthetic peptides related to dermorphin. The effects of dermorphin on EEG and autonomic variables are compared with the effects of 2 analogues and 2 homologues, all administered intracerebroventricularly in the rabbit. Dermorphin was the most effective in modifying all considered parameters: increase of cortically derived and calculated total power, bradycardia, respiratory depression and hypothermia. The dibenzylated heptapeptide was essentially inactive. The electrocortical pattern induced by the administration of L-dermorphin suggests a functional correlation between the amino acid D-ala 2 and the effects on EEG. Comparison between the effects produced by the N-terminal tetrapeptide and pentapeptide led us to hypothesize that amino acid Tyr 5 may be specifically involved in inducing the autonomic effects.


Comparative study on the behavioral and EEG changes induced by diazepam, buspirone and a novel anxioselective anxiolytic, DN-2327, in the cat. Behavioral and EEG effects of 2-(7-chloro-1,8-naphthyridin-2-yl)-3-[(1,4)-dioxa-8-(azas piro-[4.5]dec-8- yl)carbonylmethyl]isoindolin-1-one (DN-2327; 1, 5 and 20 mg/kg p.o.) were compared to those of diazepam (0.2 and 1 mg/kg p.o.) and buspirone (1 and 5 mg/kg p.o.) in freely moving cats. DN-2327 did not affect motor coordination or the relative percentages of the three sleep-wakefulness stages. Diazepam (1 mg/kg) increased wakefulness and non-REM sleep, and buspirone (5 mg/kg) also increased wakefulness and decreased REM sleep. In addition, diazepam (1 mg/kg) caused severe motor disturbance, but buspirone did not. The cortical EEG power density spectra during wakefulness were changed almost dose-dependently by DN-2327 (decreased: 2-7.75 Hz; increased: 20-49.75 Hz), and dose-dependently by diazepam (decreased: 2-7.75 Hz; increased 13-49.75 Hz) and buspirone (decreased: 4-9.75 and 13-19.75 Hz). The effect of DN-2327 on the cortical EEG varied with the sleep-wakefulness stage. The power of the 4- to 7.75-Hz frequency (theta) band of the hippocampal EEG during wakefulness was decreased by diazepam and buspirone but not by DN-2327, while the peak frequency of its spectra was decreased only by diazepam. On the other hand, during non-REM sleep, DN-2327 decreased the power of the theta band as did diazepam. These results indicate that the behavioral and EEG effects of DN-2327 differ completely from those of buspirone and considerably from those of diazepam and that the EEG effect of DN-2327 varies with the sleep-wakefulness stage.


Response of oligodendrocytes to glutamate and gamma-aminobutyric acid in the intact mouse optic nerve. The electrophysiological response to glutamate and gamma-aminobutyric acid (GABA) is determined in oligodendrocytes of the isolated intact mouse optic nerve, identified by their characteristic morphology following iontophoretic injection with horseradish peroxidase (HRP). In this study, mature myelin-forming oligodendrocytes are shown for the first time to respond to glutamate and GABA in situ, by a 2-3 mV depolarization. Morphologically homogeneous oligodendrocytes exhibit a heterogeneous response to glutamate and GABA; some cells respond to both excitatory amino acids, whereas others respond to one but not the other, and some oligodendrocytes do not respond to either. Oligodendrocytes uniformly depolarize in elevated [K+]o and it is concluded that the effect of glutamate and GABA is not mediated by an increase in [K+]o released from axons or astrocytes. The oligodendrocyte response to amino acids may be important in axon-to-oligodendrocyte signalling at the nodes of Ranvier.


Potency of depolarization-induced transmitter release is determined by divalent cation influx in PC 12 cells. Evoked release of [3H]dopamine ([3H]DA) from pheochromocytoma cells (PC 12) is dependent on extracellular calcium ([Ca2+]ex), but it can take place if calcium ions (Ca2+) are substituted by other divalent ions such as strontium (Sr2+) and barium (Ba2+). The potency of the divalent cations at supporting release varies with the cell type; in PC 12 cells the order of potency is Ba2+ > Sr2+ > Ca2+. The close correlation between depolarization-evoked Ca2+ entry and depolarization-evoked transmitter release prompted us to examine whether the higher evoked transmitter release in the presence of Sr2+ correlates with an increased evoked Sr2+ influx. Influx studies were conducted on PC12 cells using a radioactive tracer (45Ca2+ or 85Sr2+, < 1 microM) in the presence of either Sr2+ (0.5 mM) or Ca2+ (0.5 mM). Depolarization with K Cl (60 mM) increased evoked 45Ca2+ influx 2-fold when Ca2+ was substituted with Sr2+. Similarly, evoked 85Sr2+ influx increased 1.87-fold by substituting Ca2+ for Sr2+. Thus the amount of evoked cation influx is determined by the type of divalent ion which is accessible in the extracellular medium, independently of the radioactive tracer used. Increased evoked transmitter release in the presence of Sr2+ was associated with increased evoked Sr2+ influx. This suggests that the potency of evoked transmitter release is determined predominantly by the influx of divalent cations. Furthermore, the steps subsequent to cation influx in the release process are equally efficient for both cations.


The degeneration of the excitatory climbing fibers enhances [3H]MK-801 and [3H]CGP 39653 binding sites in the rat cerebellar cortex. The effect of a single injection of 3-acetylpyridine (3-AP), which led to a degeneration of the excitatory cerebellar climbing fibers, was studied on the binding of [3H]MK-801, a non-competitive NMDA antagonist, in the rat cerebellar cortex. The same treatment increased also the binding of [3H]CGP 39653, a new NMDA competitive antagonist. Saturation isotherms showed a significant increase of the maximal number of binding sites (Bmax) for [3H]CGP 39653 and [3H]MK-801 (+48 and 36% respectively) with no change in the affinity 4-9 days after the administration of 3-AP. Our data demonstrate that in the cerebellar cortex both NMDA recognition site labelled by [3H]CGP 39653 and its modulatory site labelled by [3H]MK-801 may undergo plastic changes when the glutamatergic receptors and transmission are denervated.


Dopaminergic neurons in the cat dorsal motor nucleus of the vagus, demonstrated by dopamine, AADC and TH immunohistochemistry. In the rostral part of the dorsal motor nucleus of the vagus of the cat, neurons do not contain histochemically detectable catecholamines, even though many perikarya contain both intense aromatic L-amino acid decarboxylase (AADC) immunoreactivity and strong monoamine oxidase enzymatic activity. Similarly located perikarya have distinct immunoreactivities to tyrosine hydroxylase (TH) and dopamine after treatment with colchicine. Since inhibition of monoamine oxidase fails to reveal dopamine in these cells, its absence in non-colchicine-treated animals cannot be due to rapid deamination. It appears that dopamine is synthesized by TH and AADC in dorsal motor vagal cells and is then rapidly transported from the perikarya.


Reduction of somatostatin receptors in rat hippocampus by treatment with 5,7-dihydroxytryptamine. Several lines of evidence suggest that somatostatin (SS) may interact with serotonergic neurons in the central nervous system. To assess whether SS acts presynaptically on serotonin (5-hydroxytryptamine, (5-HT)) neurons, SS receptors were measured in membranes from the hippocampus, a brain region that receives dense serotonergic innervation and has a high number of SS receptors in control and 5,7-dihydroxytryptamine (5,7-DHT)-treated rats, at 1 and 3 weeks after injection. Intracerebroventricular (i.c.v.) injection of the 5-HT-specific neurotoxin 5,7-DHT (11 micrograms (free base) dissolved in 10 microliters of isotonic saline containing 0.01% ascorbic acid) produced a 70% reduction in hippocampal 5-HT content at 3 weeks after injection but not at 1 week. This change was associated with a significant decrease in SS receptor density in rat hippocampus only at 3 weeks following the injection, without influencing the apparent affinity of the receptors at any time. Administration of 5,7-DHT did not affect somatostatin-like immunoreactivity (SSLI) levels at both times studied. These results suggest that some of the hippocampal SS receptors may be localized presynaptically on the serotonergic nerve terminals.


ACTH1-39 inputs to mesocorticolimbic dopaminergic neurons: light and electron microscopic examination. Single- and double-labeling immunocytochemical staining procedures were used to examine the relationship between adrenocorticotropin (ACTH)-containing nerve terminals and dopaminergic (DA) neurons in the rat midbrain, using both light and electron microscopy. At the light microscopic level, ACTH neuronal processes were found largely in restricted regions occupied by the mesolimbic and mesocortical DA neurons. At the electron microscopic level, in the central linear nucleus, ACTH axon terminals made symmetric and asymmetric synaptic contacts with DA dendrites, as well as appositions with unlabeled axon terminals which, in turn, synapsed upon DA dendrites. These data suggest that ACTH functions as a neurotransmitter/neuromodulator in the brain, and such ACTH-DA synapses may be important for stress-induced changes in mesocorticolimbic DA neuronal activity.


Regulation of dopaminergic activity, but not tyrosine hydroxylase, is diminished after chronic inorganic lead exposure. Previous work has indicated that the neurotoxic action of environmentally relevant levels of lead (Pb) on dopaminergic neurons is primarily presynaptic in nature and related to impaired regulation of dopamine (DA) synthesis and decreased DA release. This study was conducted to assess the functional integrity of the regulation of DA synthesis in caudate-putamen (C-P) and nucleus accumbens (NAc) of chronically Pb-exposed rats by measuring tyrosine hydroxylase (TH) activity. A pharmacological paradigm was employed that isolated autoreceptor-mediated regulation of the enzyme. At parturition dams received 0.2% Pb acetate (1090 ppm) in the drinking water while control dams received distilled water. Offspring were weaned to and maintained on the same solution given their dams until termination at 60 or 120 days. Rats were given saline or one of three DA agonists (EMD 23448, CGS 15855A, TL-99) 45 or 60 min before termination followed 15 min later by 750 mg/kg i.p. of gamma-butyrolactone (GBL) or saline. The ability of a DA agonist to prevent the GBL-induced increase in DA content was significantly altered in C-P of exposed rats compared to controls. No effect of Pb on DA content was observed in NAc. Furthermore, no differences in the ability of DA agonists to inhibit GBL-induced activation of TH in Pb-exposed compared to control animals were apparent in either brain region at either age by use of the tritium release method or the accumulation of L-DOPA. On the other hand, concentrations of DA metabolites in exposed rats given GBL and EMD 23448 were significantly lower than those in controls in both C-P and NAc. These findings support previous work suggesting that chronic Pb has multiple actions on CNS dopaminergic neurons consisting of impaired regulation of DA content and decreased DA release. However, these effects cannot be attributed to alterations in autoreceptor-mediated regulation of TH activity.


PFGE-resolved RFLP analysis and long range restriction mapping of the DNA of Arabidopsis thaliana using whole YAC clones as probes. The cleavage patterns of 23 rare-cutting restriction endonucleases (rcREs) on high molecular weight DNA, isolated from leaves of Arabidopsis thaliana (Arabidopsis), have been analysed using pulsed field gel electrophoresis (PFGE). The DNA digested with rcREs can be used for restriction fragment length polymorphism (RFLP) analysis. We show that RFLPs are more readily identified in restriction fragments that require resolution by PFGE than in smaller restriction fragments. Taking advantage of the low dispersed repetitive DNA content of the Arabidopsis genome, whole yeast artificial chromosomes (YACs) were used as probes to PFGE resolved genomic DNA. This enabled whole YAC clones to be used as RFLP markers and long range restriction maps to be constructed. These techniques should enhance the analysis of regions of the genome of Arabidopsis (and other organisms with low levels of dispersed repetitive DNA) that are the subject of chromosome walking strategies to isolate particular loci.


PCR-based RFLP analysis of DNA sequence diversity in the gastric pathogen Helicobacter pylori. DNA sequence diversity among 60 independent isolates of the gastric pathogen Helicobacter pylori was assessed by testing for restriction fragment length polymorphisms (RFLPs) in several PCR-amplified gene segments. 18 Mbol and 27 HaeIII RFLPs were found in the 2.4 kb ureA-ureB (urease) segment from the 60 strains; this identified 44 separate groups, with each group containing one to four isolates. With one exception, each isolate not distinguished from the others by RFLPs in ureA-ureB was distinguished by Mbol digestion of the neighboring 1.7 kb ureC-ureD segment. The 1.5 kb flaA (flagellin) gene, which is not close to ure gene cluster, was also highly polymorphic. In contrast, isolates from initial and followup biopsies yielded identical restriction patterns in each of the three cases tested. The potential of this method for detecting population heterogeneity was tested by mixing DNAs from different strains before amplification: the arrays of restriction fragments obtained indicated co-amplification from both genomes in each of the five pairwise combinations tested. These results show that H. pylori is a very diverse species, that indicate PCR-based RFLP tests are almost as sensitive as arbitrary primer PCR (RAPD) tests, and suggest that such RFLP tests will be useful for direct analysis of H. pylori in biopsy and gastric juice specimens.


Modulation of swimming rhythmicity by 5-hydroxytryptamine during post-embryonic development in Xenopus laevis. During the first 24 h of post-embryonic development in Xenopus laevis, a rapid change in the neural activity underlying swimming occurs in which the duration of ventral root discharge on each cycle increases from a single compound impulse to discrete bursts of activity. Moreover, this change in motor output progresses rostrocaudally, suggesting that it could result from the influence of a descending neural pathway upon the spinal rhythm-generating circuitry during early post-embryonic development. To begin to examine whether serotonergic neurons of brainstem raphe nuclei might have a role in this swimming development, we have studied the effects of 5-hydroxytryptamine (5HT) on fictive swimming in embryonic and larval animals. As previously demonstrated for other vertebrate locomotor rhythms, we find that bath-applied 5HT enhances the duration of motor activity on each cycle of larval fictive swimming. In addition, our results show that the sensitivity of the swimming rhythm to exogenous 5HT follows a strict rostrocaudal gradient. In young embryos (stages 32-36) 5HT does not affect the duration of ventral root impulses per cycle; by the time of hatching (stage 37/38), rostral but not caudal discharge is enhanced, and by stage 42 (24 h post-hatching) 5HT can increase motor burst durations along most of the length of the animal. These reversible changes induced by bath-applied 5HT closely resemble the normal rostrocaudal development of burst discharge during swimming in animals some 12 h older.(ABSTRACT TRUNCATED AT 250 WORDS)


Closure of potassium M-channels by muscarinic acetylcholine-receptor stimulants requires a diffusible messenger. The M-current (IK(M)) is a slow voltage-gated K+ current which can be inhibited by muscarinic acetylcholine-receptor (mAChR) agonists. In the present experiments we have tested whether this inhibition results from a local (membrane-delimited) interaction between the receptor and adjacent channels, or whether channel closure is mediated by a diffusible messenger. To do this, single KM(+)-channel currents were recorded from membrane patches in dissociated rat superior cervical sympathetic neurons by using cell-attached patch electrodes. Channel activity was inhibited when muscarine was applied to the cell membrane outside the patch but persisted when channels were exposed to muscarine added to the pipette solution. We conclude that a diffusible molecule (or molecules) is (are) required to induce intrapatch channel closure following activation of extra-patch receptors.


Electrophysiological characterization of a TTX-sensitive sodium current in native Xenopus oocytes. We have studied a fast inward current expressed in oocytes from one Xenopus laevis. This current was characterized as a sodium current. It was activated by depolarizations to -50 mV or higher, peaked within 3-5 ms, and then decayed following a mono-exponential timecourse. When clamped at different holding potentials, the current displayed voltage-dependent inactivation with a V0.5 of -51 mV. The channel responsible for this Na+ entry was blocked by tetrodotoxin with a K0.5 of 8 nM, and was resistant to block by lidocaine at concentrations up to 100 microM. The pharmacological similarities between neuronal and oocyte sodium channels suggest that the two channels share a conserved structure.


Wolbachia endosymbionts responsible for various alterations of sexuality in arthropods. Rickettsia-like maternally inherited bacteria have been shown to be involved in a variety of alterations of arthropod sexuality, such as female-biased sex ratios, parthenogenesis, and sterility of crosses either between infected males and uninfected females or between infected individuals (cytoplasmic incompatibility). We have characterized several of these microorganisms through partial sequences of the small (16S) and large (23S) subunit ribosomal DNA. All the symbionts identified, which include several cytoplasmic incompatibility microorganisms, several endosymbionts of terrestrial isopods, and symbionts of two thelytokous Trichogramma wasp species, belong to a monophyletic group of related symbionts, some of which have previously been detected in several insects exhibiting cytoplasmic incompatibility. Three molecular lineages can be identified on the basis of 16S as well as 23S sequences. Although they are only known as endocellular symbionts, Wolbachia spread by horizontal transfer across host lineages as evidenced by their diversification which occurred long after that of their hosts, and by the non-congruence of the phylogenetic relationships of symbionts and their hosts. Indeed, symbionts of two different lineages have been found in the same host species, whereas closely related endosymbionts are found in distinct insect orders. Isopod endosymbionts form a separate lineage, and they can determine feminization as well as cytoplasmic incompatibility. The ability to determine cytoplasmic incompatibility, found in all lineages, is probably ancestral to this group.


Psychostimulant-induced activity is attenuated by two putative dopamine release inhibitors. Centrally administered amphetamine (AMPH), cathinone, (CATH), or cocaine (COC) have each been shown to produce elevated activity in rats and this effect is dose responsive. The question remains whether these psychostimulants share a common mechanism of action (i.e., do these psychostimulants act by releasing dopamine to increase activity levels?). Experiments were, therefore, conducted to measure the spontaneous activity of these three centrally administered psychostimulants in rats following pretreatment with two putative dopamine release inhibitors, viz., 5-(4-methyl-1 piperazinyl)imidazol(2,1-b) (1,3,5)-benzothiadiazepine maleate [CGS 10746B (CGS); 20 mg/kg)] and 4-(4-benzofurazanyl)-1,4-dihydro-2,6-dimethyl-3,5-pyridinedicar boxylic acid methyl 1-methyl-ethyl ester [isradipine (ISR); 2.5 mg/kg)]. Rats fitted with chronic indwelling ventricular cannulae received a single dose of ICV-administered CATH (32 micrograms), AMPH (16 micrograms), COC (100 micrograms), or vehicle. Selection of these ICV doses of stimulant drugs was based upon results obtained in preliminary studies that indicated similar elevations of activity. ICV administration of each of these drugs/doses was preceded (20 min) by peripherally administered CGS, ISR, or vehicle. Results show that ICV CATH (32 micrograms), AMPH (16 micrograms), COC (100 micrograms) equieffectively elevate activity (two- to threefold) and that, in each case, this increase was significantly attenuated by pretreatment with CGS or ISR.


Effects of LY163502, a D2 dopaminergic agonist, on the sexual behavior of male rats. LY163502, a selective D2 receptor agonist, has been reported to stimulate sexual behavior in both copulating and noncopulating male rats. Three experiments were conducted to further characterize the role of dopamine on male sexual behavior. In the first experiment, quinelorane (LY163502) was directly infused into the medial preoptic area (MPOA) of castrated males either alone or in combination with subphysiological levels of testosterone (T) exposure. The results showed that male sexual behavior was not affected by infusion of LY163502 alone, subphysiological T levels alone, or the combination of LY163502 and subphysiological T levels. For the second experiment, all animals received physiological levels of T and MPOA infusions of LY163502 or saline. The results showed an earlier restoration of male sexual behavior in the LY163502 group when compared to the T-only group. In the third study, noncopulating, gonadally intact males received SC injections of either LY163502 or saline 30 min prior to copulatory testing. The results showed that LY163502 induced a significant decrease in mount and intromission latencies after 14 days of drug exposure. From these results, we conclude a) that D2 receptors play a role in the facilitation of male sexual behavior and b) that the action of dopamine at D2 receptors requires the presence of T.


Further studies on N-methyl-1(3,4-methylenedioxyphenyl)-2-aminopropane as a discriminative stimulus: antagonism by 5-hydroxytryptamine3 antagonists. Using a standard two-lever operant paradigm, male Sprague-Dawley rats were trained to discriminate 1.5 mg/kg N-methyl-1(3,4-methylenedioxyphenyl)-2- aminopropane (MDMA) from saline using a variable-interval 15-s schedule of reinforcement for food reward. Tests of stimulus antagonism were conducted to further define the mechanism of action of MDMA as a discriminative stimulus. Low doses of the 5-hydroxytryptamine1A (5-HT1A) antagonist NAN-190, the 5-HT2 antagonist pirenperone, and the dopamine antagonist haloperidol were able to somewhat attenuate the MDMA stimulus; however, none of these agents decreased MDMA-appropriate responding to less than 46%. The 5-HT3 antagonists zacopride and LY 278584 (ID50 = 0.02 micrograms/kg) antagonized the MDMA discriminative stimulus. Zacopride also attenuated the stimulus effects of 1-(2,5-dimethoxy-4-methylphenyl)-2-aminopropane (DOM) in DOM-trained animals but not those of (+)amphetamine in (+)amphetamine-trained animals. Several possible mechanistic interpretations are provided but it is concluded that MDMA produces its stimulus effects via a complex mechanism involving both dopaminergic and serotonergic components.


Comparison of the hyperhydrating effects of angiotensin II and isoproterenol. Administration of a single dose of angiotensin II (AII) has been shown to induce a state of hyperhydration in rats that can last from 6-10 h depending upon the route of administration and the dose. The objective of the present study was to determine whether another dipsogenic agent, isoproterenol (ISO), a beta-adrenoceptor agonist, could also induce a state of hyperhydration. The results indicate that a single SC dose of ISO can induce a hyperhydration that lasts from 4-6 h depending upon the dose administered. Administration of graded doses of either AII or ISO induced graded increases both in the time of hyperhydration and change in accumulative mean fluid exchange, (delta FE, fluid exchange of treated less fluid exchange of control). These two parameters were related linearly and directly for each drug, although the slopes, but not the intercepts, of the relationship for each drug differed significantly. Because the objective of optimal hyperhydration should be to achieve the longest duration of positive fluid balance with the least amount of ingested fluid (i.e., delta FE), the slopes of the two lines provide a convenient way to compare the hyperhydration induced by AII and ISO. By this criterion, it would appear that AII provides a more optimal hyperhydration than ISO.


Effect of mu-, kappa-, and delta-selective opioid agonists on thermoregulation in the rat. The effect of selective mu-, kappa-, and delta-agonists on brain surface temperature (Tb), oxygen consumption (Vo2), and heat exchange (Q) was studied in unrestrained, male Sprague-Dawley rats using whole-body calorimetry. Hyperthermia, produced by PL-017 (1.86 nM) given ICV, resulted from increased Vo2 and reduced Q during the first 15-45 min postinjection. Tb returned to control levels due to a combination of increased Q and reduced Vo2. PL-017-induced hyperthermia was abolished by the mu-selective antagonist CTAP (0.75 nM). Dynorphin A1-17 (4.65 nM), a kappa-selective agonist, reduced both Vo2 and Q, resulting in hypothermia that was blocked by the kappa-selective antagonist nor-binaltorphimine (25 nM). The delta-selective agonist DPDPE (4.64 nM) caused no significant changes in Tb, Vo2, or Q. The data indicate that central stimulation of the mu- and kappa-opioid receptors affects both oxidative metabolism and heat exchange, which result in a change in Tb. These alterations can be prevented with selective opioid antagonist pretreatment.


Constriction of environmental space and the behavioral response to the dopamine agonist quinpirole. The present study examines the influence of size of testing environment on the behavioral profile seen following injection of the dopamine D2 receptor agonist quinpirole (0.5 mg/kg, n = 16) or saline (n = 16). All rats were tested in a counterbalanced order in both a small and large environment. Oral (licking) behaviors were observed exclusively in the small environment and only in drug-treated rats; moreover, quinpirole increased rearing in the small but not large environment. Other behaviors--sniffing, face and body grooming--were affected by quinpirole but not in an environment-dependent manner. It is concluded that limiting environmental space promotes emergence of oral responding under quinpirole. The self-directed nature of this licking (paw- and tail-licking) may reflect a hierarchical transformation of quinpirole-induced hyperactivity from exploration of space to investigation of body parts.


Oxytocin blocks the environmentally conditioned compensatory response present after tolerance to ethanol-induced hypothermia in mice. The present study tested the hypothesis that the attenuation by oxytocin of tolerance to ethanol-induced hypothermia relies upon an impairment of the putative conditioning processes underlying environment-specific tolerance. According to the conditioning model of tolerance, such tolerance occurs because an opposite compensatory response conditioned to ethanol-paired cues attenuates ethanol's effects. Tolerance to ethanol-induced hypothermia was established to a particular environment over 4 days by injecting mice (daily) with oxytocin 2 h before ethanol, outside the colony room. As controls, other mice were injected similarly but following testing in the animal room. We found that oxytocin suppressed the conditioned compensatory response, revealed by injecting saline to every group in the tolerance-associated environment. These results suggest that oxytocin acted, at least partly, via an inhibition of the associative learning processes that facilitate tolerance development.


Role of adrenergic neuronal activity in the yawning induced by tacrine and NIK-247 in rats. The present experiments were performed to investigate the potential role of central adrenergic neurons in regulating occurrence of yawning in rats. Intraperitoneal injection of tacrine (THA) or 9-amino-2,3,5,6,7,8-hexahydro-1H-cyclopenta(b)-quinoline monohydrate HCl (NIK-247), cholinesterase inhibitors, induced yawning, which was markedly increased by pretreatment with the beta-adrenoceptor antagonist, pindolol. The yawning evoked by tacrine or NIK-247 given alone or in combination with pindolol was inhibited by pretreatment with scopolamine but not by mecamylamine or spiperone. Treatment with tacrine or NIK-247 increased acetylcholine content of the striatum, but this effect was not enhanced by pindolol, which per se did not affect basal acetylcholine content. Moreover, pretreatment with the central adrenaline synthesis inhibitors, (+-)-2,3-dichloro-alpha-methylbenzylamine HCl (LY-78335) and 2-cyclooctyl-2-hydroxyethylamine HCl (UK-1187A), increased tacrine-induced yawning. Subcutaneous injection of talipexole (B-HT 920), a dopamine D2 receptor agonist, evoked yawning, which was also increased by pindolol, LY-78335, and UK-1187A. These receptors antagonists and synthesis inhibitors per se did not cause yawning responses. The results suggest that the beta-adrenoceptor blockade and the inhibition of adrenaline synthesis facilitate the occurrence of yawning induced by cholinergic and dopaminergic agonists, and thus the central adrenergic neuronal systems may be implicated in the regulation of yawning responses.


Hyperthermia induced by the dopamine D1 receptor agonist SK&F38393 in combination with the dopamine D2 receptor agonist talipexole in the rat. The present experiments were performed to investigate the effects of dopamine D1 receptor agonists given alone or in combination with dopamine D2 receptor agonists on body temperature in rats. The selective dopamine D1 receptor agonist, 1-phenyl-2,3,4,5-tetrahydro-(1H)-3-benzazepine-7,8-diol (SK&F38393), produced hyperthermia. However, the dopamine D2 receptor agonist, B-HT 920 (talipexole), and the newly synthesized dopamine D2 receptor agonist, (S)-2-amino-4,5,6,7-tetrahydro-6-propylamino-benzothiazole (SND 919), did not change the temperature. Interestingly, the SK&F38393-induced hyperthermia was enhanced by talipexole and SND 919. The drastic hyperthermia induced by combined administration of dopamine D1 and D2 receptor agonists was blocked by either the dopamine D1 receptor antagonist, SCH23390, or the dopamine D2 receptor antagonist, spiperone. On the other hand, treatment with prazosin, yohimbine, propranolol, scopolamine, or methysergide failed to affect the marked hyperthermia. The present results suggest that a functional link between dopamine D1 and D2 receptors may be synergistic in the regulation of body temperature and that concurrent stimulation of both dopamine D1 and D2 receptors thereby produces marked hyperthermia in the rat.


Theoretical and therapeutic considerations for the anxiety disorders. Everyone is familiar with that paralyzing state of dread known as anxiety. Although it is unpleasant, the experience of anxiety has adaptive aspects: it can serve as an impetus to effect beneficial life change and can facilitate psychological development. Anxiety becomes of clinical concern, however, when it interferes with intellectual function, or arrests normal social or vocational pursuits. Anxiety disorders are chronic illnesses. Treatment can eliminate many of the disease's debilitating features, but the underlying disorder is not usually cured. Discontinuation of treatment-pharmacological, behavioral, or both-often results in the recurrence of symptoms. The focus of treatment, therefore, generally centers on striking a balance between the goal of alleviating the patient's symptoms, and the need to avoid the deleterious effects which result from long-term treatment (1). The intention of this paper is to review theoretical and therapeutic considerations for four types of anxiety disorder: panic disorder, generalized anxiety disorder, social phobia, and obsessive-compulsive disorder. In doing this, emphasis will be placed on the physiological concomitants and, when possible, neuropsychological bases of these illnesses. Furthermore, pharmacological treatment will be related to the underlying substrata of the disorder whenever possible.


Centrally acting dopamine D2 receptor ligands: agonists. The collected amount of research on D2 agonists is immense. The D2 research field has been, and still is, very dynamic. Despite this fact, only a few compounds have reached the clinic so far. At present there are clinical trials ongoing with partial D2 agonists possessing a range of intrinsic efficacies. Some of these agonists are tested for their potential effects in Parkinson's disease (high intrinsic efficacy), while others are tested for potential anti-psychotic effects (low intrinsic efficacy). An interesting possibility has arisen through the research on the synergism between D1 and D2 receptors. This could possibly be utilized in the alleviation of Parkinsonian symptomatology. The near future will show whether the compounds under evaluation hold promise for being new, valuable medicines for treating major diseases like Parkinson's disease and schizophrenia.


Pituitary adenylate cyclase activating polypeptide stimulates gallbladder motility in conscious dogs. We investigated whether pituitary adenylate cyclase activating polypeptide (PA-CAP27 and PACAP38) had any effect on gallbladder motility in conscious dogs, in which force transducers were chronically implanted in the gastric antrum, duodenum and gallbladder. PACAP27 and PACAP38 were administered intravenously during the digestive and interdigestive states at doses of 30, 100 and 300 pmol/kg. By way of comparison, cholecystokinin octapeptide (CCK-OP) was administrated at doses of 3, 9 and 27 pmol/kg. As a result, each peptide evoked transient and tonic contractions both in the digestive and interdigestive states, and the effect on the motor index was dose dependent. PACAP27 and PACAP38 were 0.11 +/- 0.03 and 0.04 +/- 0.01 as potent as CCK-OP in the digestive state, and 0.18 +/- 0.04 and 0.02 +/- 0.01 in the interdigestive state, respectively, on a molar basis. Although PACAP27 and PACAP38 belong to the vasoactive intestinal polypeptide (VIP) family, intravenous administration of 300 pmol/kg of VIP had no effect on interdigestive gallbladder motility, but on the other hand inhibited gallbladder motility in the digestive state. The contractile effects of PACAP27 and PACAP38 were almost completely abolished by pretreatment with atropine or hexamethonium, but not with L364718. An in vitro study using canine gallbladder strips showed that PACAP27 and PACAP38 had no effect on spontaneous gallbladder motor activity evoked by electric field stimulation, CCK-OP or acetylcholine. It was concluded that PACAP27 and PACAP38 stimulate gallbladder motility in conscious dogs through a preganglionic cholinergic mechanism.


A comparison of peripheral and central effects of clonidine on rat intestinal transit. This study was designed to examine the effects of centrally or peripherally administered clonidine on small intestinal transit (SIT) in rats with diarrhea. Adult, male rats weighing 200 to 250 grams were surgically implanted with a silicone catheter in the proximal small intestine. Some animals were additionally implanted with a cannula in the right lateral cerebroventricle. SIT was determined by measuring the progression of an intraduodenally administered radioactive marker (Na2CrO4, 0.5uCi) along the small intestine. In most experiments, the effects of clonidine or saline were determined in animals challenged with sodium ricinoleate (100 mg) intraduodenally, the active ingredient in castor oil except treatment with reserpine. Given subcutaneously (s.c.) clonidine significantly inhibited SIT at doses between 25 and 200 micrograms/kg. The effects of s.c. clonidine were antagonized by yohimbine, but not by reserpine or subdiaphragmatic truncal vagotomy. In contrast, given intracerebroventricularly (i.c.v.) clonidine produced a more long lasting effect at total doses greater than 20 micrograms. Intestinal antipropulsive effects of i.c.v. clonidine were blocked by yohimbine, but not by prazosin. Reserpine (s.c.) or 6-hydroxydopamine (i.c.v.) did not affect the actions of central clonidine. However, effects of i.c.v. clonidine were abolished after vagotomy. The results indicate that clonidine inhibits rat intestinal transit in similar total doses when given s.c. or i.c.v. Inhibition of SIT by clonidine results from alpha-2 adrenergic receptor activation. In the case of i.c.v. clonidine, the receptors appear to be located postsynaptically and the response is dependent upon intact vagal innervation.


Effects of gadolinium on N-methyl-D-aspartate (NMDA)-induced centrogenic arrhythmias. In urethane-anesthetized rats, the intracerebroventricular (i.c.v.) administration of N-methyl-D-aspartate (NMDA)-induced central arrhythmias. These cardiac rhythm disorders could be prevented by the i.c.v. microinjection of gadolinium, an inhibitor of exocytosis. These findings suggest that inhibition of central neurotransmitter exocytosis could protect against centrogenic arrhythmias.


Hepatic function during short-term total parenteral nutrition: effect of exposure of parenteral nutrients to light. Total parenteral nutrition (TPN) solutions either exposed to light (+L) or protected from light (-L) were infused for 5 days through jugular cannulas in freely moving rats placed in metabolic cages. At the end of the 5 day period, bile flow, biliary inorganic phosphate and biliary gamma-glutamyl transferase activity, as well as biliary concentrations of several essential and branch chain amino acids were significantly lower in the -L animals compared to +L animals. In addition, biliary glutathione was significantly lower in the +L animals. In both groups of animals, plasma tyrosine decreased significantly from pre-TPN values despite a doubling of plasma phenylalanine concentrations suggesting that tyrosine may become a conditionally essential amino acid in rats provided TPN. Our findings indicate that short-term parenteral infusion of light exposed TPN solutions alters hepatobiliary function as well as amino acid homeostasis and that the changes are minimized by light protection of the infusates. The exact mechanisms of the contribution of light exposure in the induction of hepatic dysfunction remain to elucidated.


Genome structure of spirochetes.

Genome structure of spirochetes. The genome structures of several pathogenic spirochetes have recently been determined. The genomes of Borrelia species consist of a linear chromosome of approximately one million base pairs (Mb) and various linear and circular plasmids. Analysis of restriction fragment length polymorphisms and 16S ribosomal RNA sequence data indicate the division of Borrelia burgdorferi into at least three distinct genetic groups. Leptospira interrogans has a circular chromosome 5 Mb in size and a 0.35 Mb extrachromosomal element. Repetitive sequence elements similar to insertion sequences have been identified in the Leptospira interrogans genome. The chromosome of Treponema pallidum subsp. pallidum is circular and has a size of approximately one Mb. Genetic studies conducted to date indicate that B. burgdorferi and L. interrogans have a high degree of genetic diversity, whereas remarkably few genetic differences have been observed among the pathogenic Treponema. Knowledge of the genomic structure of these organisms will serve as a basis for future genetic studies.


Structural and functional mitochondrial abnormalities associated with high levels of partially deleted mitochondrial DNAs in somatic cell hybrids. Kearns-Sayre syndrome (KSS) is a progressive and ultimately fatal human encephalomyopathy that is associated with large-scale deletions of mitochondrial DNA (mtDNA). To gain new insights into the developmental pathobiology of this disease, we studied the maintenance and expression of deleted mtDNAs (delta-mtDNAs) in somatic cell hybrids generated by fusion of HeLacot cells with a KSS fibroblast clone containing both wild-type and delta-mtDNAs. We observed that delta-mtDNAs were preferentially maintained over the KSS wild-type mtDNAs (wt-mtDNAs) in almost all isolated hybrid clones. Mitochondrial metabolism was not compromised in hybrids containing as much as 70-79% delta-mtDNAs. Two clones containing more than 99% delta-mtDNA were severely deficient in oxidative phosphorylation and exhibited abnormal, enlarged mitochondria. These clones had undetectable levels of mtDNA-encoded polypeptides, but contained normal amounts of a nuclear DNA-encoded mitochondrial protein. The data suggest a nonrandom pattern of mtDNA segregation in the triplasmic hybrids and a correlation among delta-mtDNA, structural mitochondrial abnormalities, and mitochondrial dysfunction.


Further analysis of mutant thiolase protein in fibroblasts from a Japanese boy with 3-ketothiolase deficiency. We examined the mutant protein of mitochondrial acetoacetyl-CoA thiolase (mutant T2) in fibroblasts from a Japanese boy with 3-ketothiolase deficiency. The molecular size of the mutant T2 protein, determined by pulse labeling and SDS/PAGE, was intermediate between the mature subunit and the precursor of T2. To characterize the mutant T2 protein, pulse-labeling and rhodamine 6G inhibition of mitochondrial transport in fibroblasts, cell-free translation experiments, and family studies by thiolase assay, immunoblotting, and pulse-labeling were carried out. The mutant T2 was detectable as early as a 10-min pulse. The probable precursor of the mutant T2 was not detectable in either the rhodamine 6G inhibition or cell-free translation experiments. In the parents, the K+ ion dependency of acetoacetyl-CoA thiolase activity was low and the T2 bands in immunoblots were faint. It would thus appear that the parents are heterozygotes of this disease. In pulse-labeling, only a band for the mutant T2 was detected in the patient and a single band for the normal mature subunit of T2 in the father; both bands were detected in the mother. These findings suggested that the mutant T2 in the patient was inherited from the mother, and that the expression of another mutant allele of the father may be either abolished or scanty.


The effect of ethylene glycol monomethyl ether and diethylene glycol monomethyl ether on hepatic gamma-glutamyl transpeptidase. In this paper, we determined whether ethylene glycol monomethyl ether (EGME) and diethylene glycol monomethyl ether (diEGME) induce hepatic gamma-glutamyl transpeptidase activity. Male adult Wistar rats weighing 220 g were used as experimental animals. EGME (100, 300 mg/kg per day) and diEGME (500, 1000, 2000 mg/kg per day) were administered by gavage for 1, 2 or 5 days or 4 weeks. In the 4-week study, experimental animals were administered EGME or diEGME once a day orally, 5 days/week. EGME treatment increased the serum gamma-glutamyl transpeptidase (GGT) level significantly, however, diEGME did not. The activities of three other enzymes (SGOT, SGPT and ALP) in serum were not altered by EGME or diEGME treatment and thus there was no biochemical indices of hepatic damage by EGME or diEGME. EGME treatment increased the GGT activities in the liver and lungs. Of the organs examined, the induction of GGT was the greatest in the liver. The inducibility in the liver was 216% for the 5-day treatment and 460% for the 4-week treatment. A dose-dependent increase of hepatic microsomal GGT activity by EGME was observed. On the other hand, renal GGT activities were declined to 72% and 60% of control by the 5-day and 4-week EGME treatments, respectively. DiEGME did not affect the GGT activities in any of the tissues except those of the brain. In the histochemical study, most hepatocytes at the periportal zones were stained with GGT staining after the 4-week treatment. However, the hepatocytes at the central zones were negative.


Radial mass density functions of vitrified helical specimens determined by scanning transmission electron microscopy: their potential use as substitutes for equatorial data. Using STEM dark field images, we have determined linear mass densities and radial density profiles of vitrified helical particles. The samples studied are: TMV, RNA-free helical polymers of TMV coat protein (TMV-P), Salmonella typhimurium bacterial flagellar filaments and Escherichia coli pili. The difference between the profiles obtained for TMV and TMV-P shows a maximum at a radius of about 4 nm, corresponding to the RNA in TMV. Of the peaks that are resolved in X-ray diffraction analysis we can resolve the ones for TMV at radii of approximately 4.2 and approximately 6.7 nm and a shoulder at approximately 7.8 nm. Density peaks in bacterial flagellar filaments appear at radii of approximately 4.2, approximately 6.5, approximately 8.5, and approximately 10.5 nm. Accurate mass data can be obtained if the filaments are embedded in ice layers of uniform thickness; their diameters need to be similar to that of the mass standard (TMV) when these data are measured in a comparative manner. Ice layers are often not uniform, and thickness variations are well revealed in STEM dark field. The signal-to-noise ratio and contrast for the transverse projections are lower than those measured for freeze-dried specimens: half an order and one order of magnitude, respectively. The thinnest uniformly thick ice layer still containing a single layer of particles is approximately 10-15 nm thicker than the particles. Radial mass density functions that are directly determined in STEM may have a potential use as substitutes for the unreliable equatorial data in helical reconstructions of TEM bright field images of vitrified specimens.


Extracellular matrix formation by epithelial cells from human polycystic kidney cysts in culture. Cells from the cysts of patients with autosomal dominant polycystic kidney disease (PKD) were grown in vitro under standard conditions without the aid of collagen-pretreated surfaces, and both the synthesis and composition of the extracellular matrix were investigated. At confluence, PKD cells presented the typical features of epithelial cells, but showed a different collagen composition from fibroblasts. Compared with normal tubular epithelia (NTE), PKD monolayers produced an excess of extracellular matrix, which accounted for 30% of the total incorporation of [3H] proline, although this value was considerably lower (by a factor of 10) in the case of NTE. Immunohistochemical and electrophoretic techniques revealed a complex collagen composition in the extracellular matrix which included [alpha (III)]3 and collagen IV. However, part of the collagen components remained unidentified in spite of the fact that they exhibited a typical M(r) of alpha 1(I) and alpha 2(I) in the presence of urea. Immunoprecipitation with monospecific antibodies and Northern blotting with specific probes failed to recognize alpha 1(I) and alpha 2(I), but demonstrated their presence in fibroblasts. Purification and cyanogen bromide digestion demonstrated a strong interhomology in fingerprint peptide composition among the uncharacterized collagens synthesized by PKD cells, thus suggesting a common identity. These observations document a markedly augmented production of extracellular matrix by PKD cultured cells in vitro, and show the presence of collagens which do not share homologies with the major collagen molecules. A better characterization of extracellular matrix composition is central to any comprehension of the cytogenetic mechanisms in vivo.


The level of anti-sporozoite antibodies in a highly endemic malaria area and its relationship with exposure to mosquitoes. Kilombero Malaria Project. The relationship between the humoral immune response to the conserved repeated epitope of the Plasmodium falciparum sporozoite and exposure to the mosquito vectors was examined in a study carried out in rural southern Tanzania, an area highly endemic for malaria. Considerable aggregation of the immune response between houses was observed. A statistically significant portion of this aggregation could be explained by differences in individual exposure to mosquitoes. However, two-thirds of the variance due to aggregation between households could not be accounted for, so that antibody level after controlling for exposure remained aggregated. Most of the variability in the development of the immune response was between individuals within households, and may be related to individual differences in behaviour and attractiveness to mosquitoes. The observed correlation of the immune response with exposure was due to continual exposure during several months, whereas recent exposure had almost no effect on the immune response observed in an endemic area. We concluded that in a highly endemic area the anti-sporozoite antibody level cannot be used as an indicator of recent infection and has only limited use as an indicator of continual infection.


Changes in DNA strand breaks in non-parenchymal cells following hepatocyte regeneration in CCl4-induced rat liver injury. DNA strand breaks (nicks) in non-parenchymal cells (NPCs) in CCl4-induced acute or chronic liver injury in rats were detected using an in situ nick translation method; their dynamic changes were analysed in relation to the proliferation pattern of hepatocytes and NPCs, as revealed by bromodeoxyuridine (BrdU)-uptake. In acute injury, hepatocyte proliferation started before centrilobular necrosis had occurred, whereas BrdU-labeled sinusoidal NPCs markedly increased only after centrilobular necrosis was apparent. DNA breakages in NPCs paralleled the proliferation pattern of these cells, suggesting that nicks are physiological, and reflect proliferation and activated gene expression. In chronic injury, liver cirrhosis developed after 9 weeks, but BrdU-labeling of hepatocytes was almost the same level as that in untreated liver. The number of BrdU-labeled NPCs showed only a slight increase, while those with DNA breakages were much more frequent in the cirrhotic stage, suggesting a significant role for NPCs in the fibrotic process. These results indicate that DNA strand breaks in NPCs act as a marker for activation states such as proliferation, differentiation and/or activated gene expression.


Distribution of xanthine oxidoreductase activity in human tissues--a histochemical and biochemical study. Localization of the activity of both the dehydrogenase and oxidase forms of xanthine oxidoreductase were studied in biopsy and postmortem specimens of various human tissues with a recently developed histochemical method using unfixed cryostat sections, poly-(vinyl alcohol) as tissue stabilizator, 1-methoxyphenazine methosulphate as intermediate electron acceptor and Tetranitro BT as final electron acceptor. High enzyme activity was found only in the liver and jejunum, whereas all the other organs studied showed no activity. In the liver, enzyme activity was found in sinusoidal cells and both in periportal and pericentral hepatocytes. In the jejunum, enterocytes and goblet cells, as well as the lamina propria beneath the basement membrane showed activity. The oxidase activity and total dehydrogenase and oxidase activity of xanthine oxidoreductase, as determined biochemically, were found in the liver and jejunum, but not in the kidney and spleen. This confirmed the histochemical results for these organs. Autolytic rat livers several hours after death were studied to exclude artefacts due to postmortem changes in the human material. These showed loss of activity both histochemically and biochemically. However, the percentage activity of xanthine oxidase did not change significantly in these livers compared with controls. The findings are discussed with respect to the possible function of the enzyme. Furthermore, the low conversion rate of xanthine dehydrogenase into xanthine oxidase during autolysis is discussed in relation to ischemia-reperfusion injury.


Cytopathology of PC12 cells infected with Japanese encephalitis virus. Infection of a clonal rat pheochromocytoma cell line, PC12, with Japanese encephalitis (JE) virus produced successively higher titers of virus in the culture fluid during the 72-h experimental period. In electron microscopical observation, JE virus entered PC12 cells by direct penetration through the plasma membrane at 2 min postinoculation (p.i.) and caused marked cellular hypertrophy and extensive proliferation of the cellular secretory system including rough endoplasmic reticulum (RER) and Golgi complexes starting 24 h p.i. The proliferating RER of the virally infected cells contained progeny virions and characteristic endoplasmic reticulum vesicles in its cisternae, and the proliferating Golgi complexes contained virions in their saccules. These findings indicated that the proliferation of the cellular secretory system occurred in association with viral replication and maturation in the system. Seventy-two hours p.i., the cellular secretory system of infected PC12 cells showed degenerative changes with vesiculation, disorganization, and dispersion of the Golgi complexes and fragmentation, focal cystic dilation, and dissolution of the RER in the same manner as those seen in the secretory system of JE-virus-infected neurons in the mouse brain. Thus, JE-virus-infected PC12 cells seem to be a suitable neurogenic cell line for the study of the pathogenic mechanism of JE virus. At the same time, the virally infected cells seem to offer an interesting cell model for the study of the morphogenesis of the cellular secretory system.


HTLV-II-specific antisera raised in rabbits immunized with a synthetic peptide of HTLV-II envelope protein. In order to discriminate HTLV-II from HTLV-I, HTLV-II-specific polyclonal antibodies against a synthetic peptide of HTLV-II envelope sequence were raised in rabbits. We immunized two adult rabbits with a KLH-conjugated synthetic peptide corresponding to the amino acid sequence 171-196 of the HTLV-II envelope sequence, which is a specific region for HTLV-II as evaluated with an ELISA method. The resulting rabbit antisera to the synthetic peptide reacted with gp46 of HTLV-II lysates in Western blot analysis but not with that of HTLV-I. Flow cytometric analysis and immunohistochemical study revealed that these affinity purified antisera recognized some HTLV-II-producing cell lines examined, but not HTLV-I-producing cell lines or other cell lines uninfected by HTLV. These findings indicate that these antisera specifically recognized the envelope glycoprotein (gp46) of HTLV-II and suggest the specificity of this region in the immune response to HTLV-II. Such antisera are useful in distinguishing between HTLV-I and HTLV-II infection and in determining the presence of individual HTLV-II-infected cells both in vivo and in vitro, including non-lymphoid cells. They may also assist in the elucidation of the pathogenesis of HTLV-II.


Proliferation of myocardial peroxisomes in experimental rat diabetes: a biochemical and immunocytochemical study. Myocardial peroxisomes were investigated in normal and diabetic rats. Catalase and acyl-CoA oxidase activities were increased in the diabetic rat heart and immunoblot analysis showed that both enzyme proteins were markedly enhanced in diabetic heart homogenates. After immunoenzyme staining, catalase and acyl-CoA oxidase were localized in fine granules in the myocardium, which were increased in number in diabetic rats. The numerical density of the granules stained for catalase was increased 1.7 times and that for acyl-CoA oxidase 1.8 times, compared with controls. Protein A-gold labeling for catalase and acyl-CoA oxidase was present in myocardial peroxisomes. The labeling density for both enzymes was increased in diabetic rats by 1.6 times for catalase and 1.5 times for acyl-CoA oxidase, compared with controls. The results indicate that myocardial peroxisomes are increased in the diabetic rat and that this proliferation is accompanied by an increase in catalase and acyl-CoA oxidase activities.


Distribution patterns of proinsulin and insulin in human insulinomas: an immunohistochemical analysis in 76 tumors. The distribution of proinsulin and insulin immunoreactivity was studied in 76 human insulinomas and in normal pancreas. One trabecular and two solid insulinomas showed the staining pattern of normal beta cells. A "near normal" staining pattern (perinuclear proinsulin and diffuse or polarized insulin staining) existed in 10 of 27 trabecular and 11 of 44 solid insulinomas. An "intermediate" staining pattern (intense perinuclear as well as weaker diffuse proinsulin staining with diffuse or polarized insulin staining) was observed in 10 of 27 trabecular and 20 of 44 solid insulinomas. Different "abnormal" staining patterns were found in 6 of 27 trabecular and 6 of 44 solid insulinomas. Of the 5 glandular insulinomas, 4 exhibited a "near normal" and one an "abnormal" staining pattern. No correlation was found between any particular staining pattern and the multihormonality or malignancy of the insulinomas. The diffuse labeling for proinsulin in about 50% of the insulinomas is suggestive of abnormal prohormone processing.


Three-dimensional study of epithelioid cells by a quick-freezing and deep-etching method in muramyl dipeptide-induced granulomas. The three-dimensional ultrastructure of epithelioid cells was studied by the quick-freezing and deep-etching (QF-DE), as well as the freeze-substitution (QF-FS) methods. The granulomas were induced in rats by injecting muramyl dipeptide (MDP) into the hind footpads. At 3 weeks after the injection, the footpads were perfused with a fixative, excised, and quickly frozen to prepare the replica membranes. Some unfixed footpads were also quickly frozen and freeze-substituted. Dense networks of intermediate filaments, connected with the nuclei, mitochondria and other vesicular cell organelles, were observed throughout the cytoplasm of epithelioid cells by the QF-DE method. A few actin filaments were located in filopodia and just beneath the cell membranes. Interdigitation of the cell membranes between adjacent cells was clearly demonstrated by the QF-FS method and clathrin-coated pits were identified at the base of interdigitating filopodia. In addition, the exact moment of fusion between endosomes and lysosomes was ascertained by the same method. These results suggest that the cytoskeletal organization of epithelioid cells resembles that of epithelial cells rather than actively motile macrophages.


Comparative sequence analysis and expression of bovine PrP gene in mouse L-929 cells. A cDNA clone encoding bovine scrapie-associated fibril protein, PrP, from a bovine brain cDNA library and six amplified genomic DNA clones of bovine PrP were characterized. These clones possessed specific characteristics observed in other animal PrP genes. However, the bovine PrP was divided into two types by the number of repeats. One possessed four octapeptide repetitive sequences, like other animal PrP genes, and consisted of 256 amino acids; the other had five such repetitive sequences and 264 amino acids. The amino acid sequence of the former bovine PrP agreed with that of sheep PrP up to the 165th amino acid from the N-terminus. Bovine PrP cDNA introduced into mouse L-929 cells were stably expressed. The expression level of recombinant bovine PrP in the cells judged by immunofluorescence was higher than that of authentic mouse PrP. The recombinant PrP comigrated with authentic bovine PrP in SDS-polyacrylamide gel electrophoresis, suggesting that the recombinant product was fully glycosylated in L-929 cells. Distinct bundles of the intermediate filaments were frequently seen at the perinuclear region of the cells.


[Lipid peroxidation and erythrocyte membrane function in congenital heart defects in relation to the use of beta-adrenoblockers]. Oxygen tension in the blood and tissues, lipid peroxidation (LP) intensity (content of malonic blood dialdehyde and activity of superoxide dismutase in erythrocytes), spectrum of fatty acids and phospholipid composition of erythrocytic membranes, their passive K(+) permeability, total ATP content in erythrocytes, some other metabolic indices were investigated in 24 patients with blue type congenital heart disease. It was shown that these patients showed a reduced oxygen tension in the blood and tissues, LP intensification, changes of the lipid phase of erythrocytic membranes, disorders of their permeability, decrease of intraerythrocytic ATP reserves. Beta-adrenoblocking agents (obsidan, anaprilin were used in 10 patients. Reported are clinico-metabolic findings indicating a favourable effects of these drugs on LP processes, lipid spectrum of erythrocytic membranes, their permeability and bioenergy reactions.


[Enzyme activity in the blood serum as a criterion of the severity of acute cholecystopancreatitis]. The activity of lactate dehydrogenase, gamma-glutamyltranspeptidase, alkaline phosphatase, 1-antitrypsin was studied in 30 patients with acute cholecystopancreatitis of different severity grades. It was found that changes of activity of these enzymes depending on the severity of the disease may be considered as a criterion of regression of the inflammatory changes in the biliary-pancreatic zone as well as a criterion of recovery.


[The pharmacological correction of reflex stenocardia due to chronic noncalculous cholecystitis]. Results are reported of a study of the effect of benzohexonium electrophoresis on the epigastric area in cardiac syndrome due to chronic noncalculous cholecystitis in 72 patients. This treatment produced a favourable effect in reflex stenocardia as confirmed by data of clinical and paraclinical findings. The authors recommended to include benzohexonium electrophoresis in patients with the biliary cardiac syndrome in the complex treatment of patients with chronic cholecystitis.


[Myocardial calcinosis in a juvenile patient with Wermer syndrome (multiple endocrine neoplasia type I)]. We describe the rare case of a 19 year-old patient with multiple endocrine neoplasia (Wermer syndrome), presenting with insulinomas as well as primary hyperparathyroidism. Echocardiography revealed evidence of calcific deposits in the interventricular septum. The latter may be explained by long-standing hypercalcemia.


[The status of H2-blocker therapy today]. In the light of recent findings the therapeutic importance of various H2-blockers (e.g. cimetidine, ranitidine, famotidine) in short-term and long-term treatment of peptic ulcers is discussed. Special interest is paid to the clinical pharmacology (pharmacokinetics, pharmacodynamics) and undesired effects of the compounds. New aspects in the pathogenesis of peptic ulcer disease were considered, with regard to the pharmacologic profile of H2-blocker.


Reactogenicity and immunogenicity of inactivated hepatitis A vaccines. Two inactivated hepatitis A virus (HAV) candidate vaccine strain were tested, derived from strains CLF and HM175. Neither vaccine increased liver enzymes levels and reactogenicity was similar to that observed with other alum-absorbed products. Antibody responses were dose-dependent and protection against HAV can be presumed to last for at least three years. All persons receiving 720 ELISA units (El.U) of the CLF vaccine seroconverted after one dose. For the HM175 vaccine, anti-HAV persisted until month 12 after injections at months 0 and 1, suggesting that the third dose of vaccine could be given at any time from month 6 to 12. A double dose of HM175 vaccine (1440 El.U) given as a single bolus resulted in 100% seroconversion by day 14 with a geometric mean anti-HAV level of 121 mIU/ml. This implies that rapid protection can be induced using large doses of inactivated HAV vaccine should time constraints dictate such an approach.


Polyarteritis nodosa with atrophy of the left hepatic lobe. A 73-year-old Japanese man with a history of partial gastrectomy due to gastric cancer 4 years previously was admitted because of intermittent fever. The patient developed abdominal pain, erythema, and myalgia in addition to the fever during the final clinical course, and died of acute heart failure. Autopsy disclosed atrophy of the left lobe of the liver and acute myocardial infarction. Neither metastasis nor recurrence of the cancer was observed. Small- and medium-sized arteries of the visceral organs showed various stages of necrotizing vasculitis with narrowing of the lumina. The vasculitis was most prominent in the left lobe of the liver and in the heart. Narrowing of the portal vein due to portal tract inflammation in addition to vasculitis of the hepatic arteries may have induced ischemia and infarction, which had resulted in atrophy of the left hepatic lobe.


Expression of c-fos protein in serotonergic neurons of rat brainstem following electro-acupuncture. The c-fos proto-oncogene encodes a nuclear phosphoprotein, Fos which has been proposed to be a "third messenger" coupling short term extracellular signals to long term alteration in cell function. Using double labeling immunocytochemistry, the present work demonstrated the co-localization of Fos protein and serotonin in the nucleus raphe dorsalis, nucleus raphe centralis superior and rostral ventromedial medulla. The results pose an interesting problem, the possible relation of Fos protein to the biosynthesis of serotonin, awaiting further investigation.


Hyperglycemic athymic nude mice: factors affecting in vitro insulin secretion. The strain of athymic nude male mice (ANM) developed at the University of Southern California (USC) exhibits spontaneous hyperglycemia and relative hypoinsulinemia in vivo. To investigate factors that influence insulin secretion in this animal model of non-insulin-dependent diabetes mellitus, we utilized the isolated perfused mouse pancreas of the ANM-USC and control BALB/c mice. We compared in vitro glucose-induced insulin secretion in ANM-USC and control mice, inhibition of secretion by somatostatin, and variability of insulin secretion over the two-year period it took to complete these experiments. Glucose-induced insulin secretion from the isolated pancreas was biphasic in both ANM-USC and controls. Insulin secretion was quantitatively equal to or greater than control mice, depending on the phase of secretion analyzed and the source of the control mice. In contrast to pancreases of control mice, insulin secretion from ANM-USC pancreases was relatively resistant to inhibition of insulin secretion by somatostatin. Variability in insulin secretion over the two years in which these experiments were performed was greater from pancreases of control than that observed from pancreases of the ANM-USC. The hyperglycemic ANM-USC mouse does not demonstrate diminished insulin secretion in vitro yet is relatively hypoinsulinemic in vivo. Thus circulating factors other than somatostatin might contribute to the insulinopenic stage in this animal model.


Acupuncture for low back pain in huang di nei jing su wen. (Yellow Emperor's Classic of Internal Medicine Book of Common Questions). In Huang Di Nei Jing Su Wen, among the materials which heretofore have no English translation, there are three Chapters on pain. One of them was devoted entirely to the low back pain. This is certainly an indication of its importance even more than 2,300 years ago. Since it still plagues us nowadays, we have translated that Chapter of this medical classic to see what we can learn from the ancients. We attempted to second guess the ancients in the diagnosis of the various sets of symptoms, in the light of western medicine. We discussed the difficulties in interpreting the archaic text. We pointed out that there were associations of the Mais (i.e., the Meridians) with various sets of symptoms but the loci of puncture were rather vaguely described and had no names. We inserted our selections of currently used acupoints to match the described loci. We would like to solicit our readers' comments.


Real-time evaluation of anaerobic threshold with rms-EMG of working and nonworking muscles during incremental bicycle ergometer test. Surface rms-EMG measurement as a real time monitoring method for detecting the anaerobic threshold during a bicycle ergometer test was evaluated and compared with blood lactate and ventilatory parameters. The study group consisted of 12 healthy ice hockey players. The anaerobic threshold indicated as dislinearity of increase in blood lactate level, ventilatory parameters and myoelectrical activity was observed at the work level of 300 (range 270-330) W in each case. The linearity disappeared at same time in the rms-EMG-load ratio both in working (quadriceps and gastrocnemius) and nonworking (frontalis) muscles. The rms-EMG follow-up was easier to perform than measurements of blood lactate and ventilatory parameters.


Exercise interrupts ongoing glucocorticoid-induced muscle atrophy and glutamine synthetase induction. This study was undertaken to determine whether regular endurance exercise is a deterrent to a developing state of muscle atrophy from glucocorticoids and to evaluate whether the contractile activity antagonizes the hormonal actions on glutamine synthetase, alanine aminotransferase, and cytosolic aspartate aminotransferase (cAspAT). Adult female rats were administered cortisol acetate (CA, 100 mg/kg body wt) or an equal volume of the vehicle solution for up to 15 days. Exercise (treadmill running at 31 m/min, 10% grade, 90 min/day) was introduced after 4 days of CA treatment, at which time plantaris and quadriceps muscle mass had been reduced to 90% of control levels. Running for 11 consecutive days prevented 40 mg of the 90-mg loss and 227 mg of the 808-mg loss that were subsequently observed in plantaris and quadriceps muscles, respectively, in the sedentary animals. Glutamine synthetase mRNA and enzyme activity were elevated threefold by glucocorticoid treatment in the deep quadriceps (fast-twitch red) muscles after 4 days. Initiating exercise completely interfered with the further hormonal induction (to approximately 5-fold) of this enzyme and, after 11 consecutive days of the exercise regimen, glutamine synthetase mRNA and enzyme activity were 58 and 68% of values from CA-treated sedentary animals. In vehicle-treated groups, basal levels of glutamine synthetase expression were also diminished by exercise to approximately 40% of the values in sedentary controls. Hormone treatment did not alter either aminotransferase enzyme activity but reduced cAspAT mRNA in fast-twitch red muscles by 50%. Exercise abolished the glucocorticoid effect on cAspAT mRNA.(ABSTRACT TRUNCATED AT 250 WORDS)


Human colon cancer cells express ICAM-1 in vivo and support LFA-1-dependent lymphocyte adhesion in vitro. Intercellular adhesion molecule-1 (ICAM-1) is a cell surface adhesion glycoprotein that mediates leukocyte adhesion through interaction with the leukocyte CD11/CD18 adhesion complex. The aim of this study was to determine whether ICAM-1 is expressed by normal or neoplastic colonic epithelial cells. Immunohistochemical studies on human colonic tissue demonstrated focal ICAM-1 expression by colonic carcinomas but not by normal colonic epithelium. ICAM-1 expression by colonic carcinomas showed a positive correlation with the presence of a peritumoral inflammatory infiltrate. Surface expression of ICAM-1 was also observed in HT-29 cultured human colon cancer cells by both immunohistochemistry and enzyme immunoassay. Interferon-gamma and interleukin-1 beta significantly increased ICAM-1 surface expression by HT-29 cells in a dose-dependent manner. Upregulation of ICAM-1 surface expression became evident some hours after cytokine stimulation and was inhibited by both actinomycin D and cycloheximide, indicating a requirement for de novo RNA and protein synthesis. HT-29 monolayers supported adhesion of human lymphocytes as determined by a quantitative 111In-labeled leukocyte adhesion assay. Adhesion was mediated in part via interaction of ICAM-1 on HT-29 cells with lymphocyte function-associated antigen-1 (CD11a/CD18) on lymphocytes, as defined by using blocking monoclonal antibodies. Expression of ICAM-1 and/or other leukocyte adhesion receptors by neoplastic epithelial cells may play a role in directing leukocyte trafficking and leukocyte-epithelial cell interactions in colonic carcinoma.


Somatostatin restraint of gastrin secretion in pigs revealed by monoclonal antibody immunoneutralization. We studied the functional coupling between antral somatostatin and gastrin cells in isolated perfused porcine antrum using immunoneutralization with monoclonal antibodies against somatostatin. Their binding affinity was 10(11) l/mol, and the final binding capacity was 11.7 nmol/ml. Antibody infusion within 1 min increased gastrin secretion, reaching a rate of 349 +/- 64% (means +/- SE, n = 7) of basal secretion (59 +/- 5 pmol/l) after 5 min. The effect of somatostatin at 10(-9) mol/l, which inhibited gastrin secretion from 58 +/- 11 to 14 +/- 3 pmol/min (n = 4), was abolished by antibody infusion. Electrical stimulation of the vagus nerves (n = 7) performed during antibody infusion increased gastrin secretion from 224 +/- 61 to 328 +/- 55 pmol/min, not significantly different from the increase in control experiments from 43 +/- 9 to 118 +/- 20 pmol/min, indicating that the vagal stimulation of gastrin secretion does not depend on mechanisms involving somatostatin. We conclude that paracrine antral somatostatin secretion is one of the most important factors regulating basal gastrin secretion in pigs.


An introduction to sequential electric acupuncture (SEA) in the treatment of stress related physical and mental disorders. A method of sequential electrical stimulation to certain acupuncture loci was found to be effective in the treatment of stress related physical and mental disorders. Recent research found that cerebral serotonin has anti-depressant and analgesic effects. It was reported that cerebral serotonin can be released by the stimulation of certain acupuncture loci. Omura reported that the stimulation of ST36 and GB20 increased intracephalic blood flow. Increasing intracephalic blood flow may indirectly increase the quantity of serotonin released. The release of serotonin can be enhanced further by sequential stimulation of these acupuncture loci. A marked degree of mental relaxation by SEA was shown in this study of 85 clinical cases of chronic physical disorders, e.g. intractable pain, headache, with most disorders complicated by reactive depression. Some of the cases were psycho-somatic disorders. The percentage of improvement from slight to remarkable between mental disorders (78.8%) and physical disorders (77.1%) is about equal. The method of treatment and schematic of the SEA device are discussed and shown.


Effects of the electrical stimulation of myofascial trigger points with tension headache. The effects of electrical stimulation by simple pocket size stimulator were evaluated on myofascial trigger points by pain threshold (PTH) algometry. The study consisted 14 patients with 76 treated trigger points in randomly selected double blind cross-over study protocol. The effects of 30 seconds stimulation increased the PTH values 0.58 kg/cm2 in study group, but only 0.13kg/cm2 in controls (p < 0.01). These results suggested that the stimulation had positive effects on myofascial trigger points, but these effects were seen only on the treated points.


Myogenic mechanism for peristalsis in opossum smooth muscle esophagus. We studied the propagation of phasic contractions initiated by tetraethylammonium (TEA, 1-10 mM), high K+ concentration (10-30 mM), and bethanechol (10(-6) to 10(-2) M) in a whole organ in vitro preparation of the opossum smooth muscle esophagus. TEA initiated phasic contractions that began at all sites along the smooth muscle esophagus and propagated in both directions with a velocity similar to that of primary peristalsis. Blockade of neural transmission by tetrodotoxin (TTX, 10(-7) M) did not prevent contraction propagation. Although a majority of contractions initiated by TEA did not propagate the full length of the esophageal specimen, with the addition of TTX most contractions initiated by TEA did propagate the full specimen length in either direction. High K+ concentration and bethanechol elicited propagated contractions similar to those initiated by TEA. We conclude that 1) a myogenic mechanism exists for propagation of contractions along the smooth muscle esophagus and 2) intramural inhibitory nerves modulate the extent of myogenic propagation in the ascending as well as descending direction. We suggest that esophageal peristalsis may occur by myogenic propagation of contractions that are normally initiated in the proximal smooth muscle esophagus by excitatory nerves. Intramural inhibitory nerves may inhibit retrograde propagation as well as mediate descending inhibition in advance of the peristaltic wave.


[Effects of intravenous anesthetics on neurons of the central nervous system: mechanisms of cellular and molecular action]. The mechanisms of action of intravenous anaesthetics are not yet completely elucidated. Until recently, most of the studies had focused on the interactions between anaesthetics and lipid bilayers. It has been proposed that loss of consciousness is produced by disorganization of the lipid phase of nerve membranes, which impairs the action potential propagation. However, new data obtained with sophisticated neuropharmacological tools such as the patch clamp technique have recently contributed to challenge this hypothesis. Indeed, several lines of evidence suggest that intravenous anaesthetics are thought to induce loss of consciousness by blocking the excitatory synaptic transmission. This can be achieved presynaptically, by inhibiting glutamate release from nerve endings via alterations in the gating properties of voltage-dependent calcium channels. Blockade of excitatory synaptic transmission can also occur at the postsynaptic level by antagonizing the glutamate receptors of the N-methyl D-aspartate subtype. Some anaesthetic agents including ketamine also block the nicotinic receptors, however the relevance of this finding with respect to clinical anaesthesia requires further investigation. Preliminary data also suggest that propofol and etomidate elicit uncoupling of gap junctions between astrocytes, which represent a major nonneuronal cell population in the central nervous system. This phenomenon might indirectly contribute to the hypnotic action of these compounds. Whether loss of consciousness involves preferential target structures within the brain remains to be delineated. A better understanding of the mechanisms of action of general anaesthetics might contribute to generate new agents with more pharmacological selectivity and less undesirable side-effects.


Effect of age on activation of porcine intestinal guanylate cyclase and binding of Escherichia coli heat-stable enterotoxin (STa) to porcine intestinal cells and brush border membranes. Development of age-dependent resistance to enterotoxigenic Escherichia coli was studied, using isolated enterocytes and brush border membranes (BBM) from 7-day-old and 7-week-old pigs. Binding of 125I-labeled heat-stable (125I-STa) enterotoxin to enterocytes and BBM was specific, temperature- and time-dependent, saturable, and partially reversible. Scatchard analysis revealed a single class of receptors. Mean +/- SD avidity of binding (apparent affinity constant, Ka) of 125I-STa to enterocytes from 7-day-old and 7-week-old pigs was 2.14 +/- 0.29 x 10(8) and 2.72 +/- 0.25 x 10(8) L/mol, respectively. Numbers of STa receptors were calculated to be 64,903 +/- 2,900/enterocyte for 7-day-old pigs and 53,029 +/- 3,117/enterocyte for 7-week-old pigs. Numbers of STa receptors expressed per milligram of BBM protein from 7-day-old pigs were 2.66 x 10(11), compared with 2.29 x 10(11) for BBM from 7-week-old pigs. By 5 minutes after addition of STa to reaction mixtures, intracellular cyclic guanosine monophosphate concentration increased 13.9-fold in enterocytes from 7-day-old pigs and 8.7-fold in enterocytes from 7-week-old pigs. The particulate guanylate cyclase activity associated with BBM from 7-week-old pigs was slightly more sensitive to low amounts of STa, compared with BBM from 7-day-old pigs; however, differences were not observed at intermediate and high amounts. These data indicate that lack of a secretory response to STa by older pigs is not attributable either to decreased numbers of STa receptors or to decreased signal response between the STa receptor and membrane-bound guanylate cyclase.(ABSTRACT TRUNCATED AT 250 WORDS)


Aggressive behavior and the brain: a different perspective for the mental health nurse. Mental health nurses often provide care to individuals who have the potential for aggressive behavior. The expression of such behavior is influenced by the functioning of the central nervous system (CNS). The authors present a framework to assist the reader to understand the interrelationships among the limbic system, and frontal and temporal lobes as they relate to the expression of aggressive behavior. The implications for mental health nursing practice include detecting contributing factors such as head injury, temporal lobe epilepsy, alcoholism, and dietary imbalances, and interpreting patient behaviors to colleagues. Suggestions for proactive interventions are also included.


Symptom monitoring in schizophrenia: potential for enhancing self-care. In this study a symptom self-regulation model was used as a framework to examine the characteristics and stability of indicators of illness identified by individuals with schizophrenia. Subjects were interviewed to determine if they could identify indicators of illness and describe characteristics of their primary indicator. Primary indicators of illness from 51 subjects were categorized as anxiety-based, depressive, or psychotic. Subjects who identified psychotic indicators were more confident that their indicator occurred when they were getting ill than subjects with anxiety-based or depressive indicators, and subjects who identified psychotic and depressive indicators reported that their indicators were more troublesome than those identifying anxiety-based indicators. Anxiety-based indicators were reported by subjects to occur more frequently than indicators from the other two categories. Findings from a follow-up interview of 28 subjects 1 year later showed that approximately half reported either the same primary indicator of illness or identified an indicator in the same category (anxiety-based, depressive, or psychotic) as they had 1 year previously. The implications of the findings for enhancing self-care through monitoring symptoms are discussed.


Antipsychotic drug doses in a schizophrenia inpatient unit. Dose-effect studies have found that 600 mg/day of chlorpromazine (or its equivalent) is generally sufficient to treat acute psychosis. This paper reports on the doses of antipsychotic medication prescribed for inpatients in a Schizophrenia Unit at an Australian state hospital. Fifty five percent of patients received daily doses equivalent to more than 600 mg of chlorpromazine and 26% received daily doses equivalent to more than 1500 mg of chlorpromazine. Low potency drugs were prescribed in lower doses than high potency drugs. Patients prescribed depot medication tended to receive higher doses of medication than those prescribed oral medication only.


Treatment of childhood anxiety disorders using behaviour therapy and pharmacotherapy. Although the treatment of childhood anxiety disorders can be approached from numerous theoretical perspectives, the concentration of research has been on the efficacy of behaviour therapy. Behaviour therapy procedures are briefly described and evaluated, including systematic desensitisation, flooding, modelling, reinforcement and cognitive procedures. We also review research findings on pharmacotherapy, focusing on benzodiazepine and antidepressant usage. Finally, several conclusions are drawn concerning the scientific and clinical status of these treatment approaches for childhood anxiety disorders.


Psychotic symptoms preceding ocular deviation in a patient with tardive oculogyric crises. This report describes a patient with schizophrenia who developed episodes of ocular dystonia as a delayed side effect of neuroleptic medication. Each episode was preceded and accompanied by marked agitation, stereotypic behaviour and exacerbation of hallucinations. Both the psychotic and dystonic symptoms responded to anticholinergic medication. The theoretical and practical implications of this observation are discussed.


Co-variation between biological markers and self-reported alcohol consumption. A two-year study of the relationship between changes in consumption and changes in the biological markers gamma-glutamyl transpeptidase (GGT) and average volume per erythrocyte (MCV) among problem drinkers. Co-variations between self-reported alcohol consumption and the biological markers MCV (average volume per erythrocyte) and GGT (gamma-glutamyl transpeptidase) over a 2-year period were studied in a group of 84 men and 53 women recruited to out-patient treatment by advertisements in the press. Upon admission, the drinking pattern of the participants during the preceding year was registered in detail. The participants were also medically examined, and blood samples taken. All the participants were followed up by new personal interviews, medical examinations and new blood sampling after 3, 9, 25 and 21 months. For the group as a whole, alcohol consumption was significantly lower at the end of the observation period than at admission. GGT was also decreased, but not MCV. Both self-reported consumption and the values for the biological markers showed large inter-individual and intra-individual variations during the observation period. The biological markers seemed to co-vary to a limited degree with changes in reported consumption. Both GGT and MCV seemed to have a low sensitivity but a high specificity to changes in consumption. Both markers also seemed to be somewhat more useful in identifying decreases than increases in consumption. The markers GGT and MCV should be used with caution in connection with therapeutic counselling to individuals.