Metabolic effects of carteolol and dilevalol in essential hypertension
As further classes of antihypertensive agents become available, more attention is being directed toward the ancillary pharmacological activities of the drugs, such as metabolic effects, fl-Adrenoceptor blockers are known to produce different effects on serum lipids, depending on their pharmacological characteristics [1, 2]; for example, non-cardioselective ffblockers without intrinsic sympathomimetic activity (ISA) have been reported to raise triglycerides and to lower HDL-cholesterol [3, 4], while cardioselective flz-blockers show less of this adverse effect [5], and/3-blockers with ISA appear to cause the least alteration in serum lipids [6]. Nevertheless, the precise reasons why/3-blockers with ISA have a less unfavourable effect on lipid metabolism than those without ISA remains unclear. The present study was designed to assess whether a fl-blocker with partial selective ~-adrenoceptor agonism would have any advantageous metabolic effects when compared to a convectional/3-blocker with ISA. The metabolic effects of carteolol (10 mg, once daily), a/3-blocker with potent intrinsic sympathomimetic activity [7, 8], and dilevalol (100 mg, once daily), a/3-blocker with fl2-selective ISA [9], have been in compared 9 patients with untreated mild-to-moderate, otherwise uncomplicated, essential hypertension (WHO Classes I and II) in a randomised, two-way, cross-over trial, following a 2-week run-in control period. Blood samples for measurement of serum lipids, creatine phosphokinase (CK), uric acid and glycosylated haemoglobin Ale (HbAlc), an indicator of glycaemic control, were obtained from each of the patients after a 12-h overnight fast at the end of the 2-week run-in and of 6-week fixed maintenance periods of carteolol and dilevalol. The results are summarized in Table 1. Six-week oral monotherapy with carteolol and dilevalol significantly lowered (P<0.01) both systolic and diastolic blood pressure to a similar extent as compared to the predose values. Total serum cholesterol, triglycerides, low(LDL) and high-density lipoprotein (HDL) cholesterol and the LDL/HDL-cholesterol ratio were not altered by either drug. The serum CK level was significantly increased (P < 0.05) by carteolol ( + 23 %) and dilevalol ( + 27 %) as compared to the predose level. Serum uric acid and HbAzc remained unchanged