Biochemical and behavioural studies on the interference between catecholaminergic and serotonergic central systems.

L H Allikmets; A M Zharkovsky

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PubMed · 40501

Biochemical and behavioural studies on the interference between catecholaminergic and serotonergic central systems.

L H Allikmets·A M Zharkovsky

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Abstract

L-DOPA, apomorphine and amphetamine increase emotional reactivity and aggressiveness, and/or evoke spontaneous attack behaviour in male rats. At the same time these compounds accelerate the turnover of endogenous serotonin (5-HT), increasing the brain concentration of 5-HIAA. L-DOPA, amphetamine and apomorphine antagonize the depressive effects of 6-tryptophan on behaviour. After the injection of L-tryptophan these dopaminomimetics facilitate the turnover of 5-HT in the brain. On the other hand, the tranquillizing effect of L-tryptophan correlates not only to the increased level of 5-HT but also to an accelerated catabolism of dopamine. After the simultaneous injection of L-DOPA and L-tryptophan, cross-influence on the turnover of 5-HT and dopamine is noted, while in behaviour the effects of L-DOPA prevail over those of L-tryptophan. PCPA blocks the behavioural effects of dopaminomimetics.

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Adrenergic alpha-Agonists Amphetamine Animals Apomorphine Behavior, Animal Brain Dopamine Exploratory Behavior Levodopa Male Motor Activity Rats Serotonin Tryptophan Journal Article

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L H Allikmets, A M Zharkovsky. 1978. Biochemical and behavioural studies on the interference between catecholaminergic and serotonergic central systems.. https://pubmed.ncbi.nlm.nih.gov/40501/

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