In vivo release of endogenous dopamine from rat caudate nucleus by beta-phenylethylamine and alpha,alpha,-dideutero-beta-phenylethylamine.

The release of endogenous dopamine (DA) has been measured in the rat striatum following the intracardial administration of various doses of beta-phenylethylamine (PEA) or alpha,alpha-dideutero-beta-phenylethylamine (deuterated PEA). The release was significantly increased for a period of approximately 15 minutes by a dose of 25 mg/kg PEA. Both the dose required to stimulate DA release and the duration of the effect were in good agreement with previously reported behavioral and locomotor effects of administered PEA. When the animals were given 25 mg/kg of deuterated PEA, the increase in DA release was both longer lasting and significantly greater in magnitude than that observed in response to the non-deuterated amine. The results of these experiments provide direct evidence that DA release is stimulated by amounts of PEA known to cause behavioral effects and locomotor activity in rats, and suggest that these effects are likely to be mediated, at least in part, by DA.