COMPARISON OF THE BRAIN LEVELS OF N,N-DIMETHYLTRYPTAMINE AND ALPHA,ALPHA,BETA,BETA-TETRADEUTERO-N,N-DIMETHYLTRYPTAMINE FOLLOWING INTRAPERITONEAL INJECTION - THE INVIVO KINETIC ISOTOPE EFFECT

A comparison of the rat brain levels (.mu.g/g wet wt of tissue) of the hallucinogen N,N-dimethyltryptamine (DMT) and its deuterated analog .alpha.,.alpha.,.beta.,.beta.-tetradeutero-DMT (D4DMT) as a function of time and dose is reported. The presence of deuterium in the .alpha.- and .beta.-positions of the ethylamine side-chain led to a potentiation of the level of DMT in brain. Strikingly different dynamics of uptake and clearance were also noted. These results may be due to a primary kinetic isotope effect, illustrating the importance of the .alpha.-position in the metabolism of DMT.