[Comparative effect of the psychostimulants sidnocarb and fenamin on the tyrosine hydroxylase activity of the brain synaptosomes in rats].

A single administration of the psychostimulant sydnocarb activates tyrosine hydroxylase (TH) in synaptosomes of rat brain hypothalamus and striatum. The inhibitory effect of dopamine (DA) in synaptosomes of the striatum is potentiated. A single administration of amphetamine activates the response in synaptosomes of the hypothalamus and activates it in the striatum. Amphetamine does not exert any effect on the inhibitory effect of DA. Chronic administration of sydnocarb activates synaptosomal TH in the hypothalamus and inhibits it in the striatum. Fifteen minutes after the last injection of the two-week sydnocarb treatment the regulatory effect of DA in respect to tyrosine hydroxylation is considerably reduced. Thirty minutes after the concluding injection of the 2-week amphetamine treatment TH is found to be activated in the hypothalamus and inhibited in the striatum. Twenty-four hours after the treatment is completed the reverse relations are observed. The regulatory inhibitory effect of DA in respect to TH was significantly reduced in both versions of experiment.