[The influence of amphetamine on changes in the brain neuromediator metabolism].
Vistar rats (stress resistant) and August rats (stress-sensitive) were injected with one-time d,l-amphetamine dosages of 1,0 and 2,5 mg/kg. Specific activity of enzymes involved in dopamine and serotonin metabolism - tyrosine hydroxylase, tryptophan hydroxylase, monoaminooxidase, types A and B - was determined and l-dioxyphenylalanine content measured in brain subfractions (sensomotor cortex and striatum). August rats differed from Vistar rats by enzyme activity indices as well as by neuronchemical index expressing a ratio of the specific activity indices of enzymes studied in the sensomotor cortex and the striatum. The neuronchemical index allowed to reveal the characteristic imbalance of dopamine and serotonin metabolism between the cortex and subcortical regions in the brain of August rats that, apparently, determined their stress sensitivity and clearly demonstrated the peculiarities of different amphetamine dosage effect on the animal brain neuromediator metabolism with different stress resistance.