Effects of barbital and disulfiram on the metabolism of intracerebroventricularly administered [14C]-5-hydroxytryptamine in rats

Effects of barbital and disulfiram on the metabolism of serotonin (5-HT) in vivo were studied. One hr after intracerebroventricular injection of [14C]-5-HT (3 nmoles, 0.5 muCi), the levels of the total and deaminated radioactive materials were increased in rats receiving either barbital or disulfiram, as compared to those of control rats. In addition, an additive effect was observed by a combined administration of these two drugs. The results in this paper strongly suggest that barbital and disulfiram inhibit the metabolism of 5-hydroxyindoleacetaldehyde (5-HIAAld), a first deaminated metabolite in 5-HT metabolism.