Rat Brain Supernatant Research Articles

Influence of chlorpromazine on decarboxylases of aromatic amino acids

In vitro 10 −4 M chlorpromazine did not influence decarboxylation of 5-hydroxytryptophan (5HTP) and 3 : 4-dihydroxyphenylalanine (dopa) in supernatant of rat brain and kidney. 10 −3M chlorpromazine only inhibited dopa decarboxylation in brain supernatant to which no pyridoxal-5′-phosphat (py-5-p) had been added. Pretreatment of intact rats with high doses of chlorpromazine had no significant effect on decarboxylation of dopa or 5HTP in total homogenates or supernatant of brain. In supernatant of kidney of rats pretreated with chlorpromazine there was, however, a 30–70 per cent rise in decarboxylation of dopa and 5HTP, provided that no py-5-p was added to the incubation medium. The results are discussed with regard to the effects of chlorpromazine on the metabolism of py-5-p and aromatic monoamines.