Formation of a Novel and Neurotoxic Tetrahydroisoquinoline Derivative, 1,3-Dimethyltetrahydroisoquinoline (1, 3DiMeTIQ), a Condensation Product of Amphetamines and Acetaldehyde in Vivo
d-Amphetamine and alcohol are generally thought to be mutually antagonistic with respect to their pharmacological action. However the toxic effect of d-amphetamines is not appreciably reduced by the concomitant administration of alcohol.1 It is reported that the combined abuse of methamphetamine and alcohol causes a significant increase in psychosomatic disorders than the abuse of methamphetamine only.2 We hypothesized that a novel metabolite of amphetamines may be involved in such disorders and proposed that 1,2,3,4-tetrahydroisoquinoline (TIQ) and 1-methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ) are formed by ring cyclization of endogenous phenylethylamine.3–5 In the present study, we examined the possibility that 1,3DiMeTIQ could be formed from exogenous amphetamines, an analog of phenylethylamine, by cyclization with acetaldehyde, a metabolite of ethanol (Fig. 1).
KeywordsBiogenic Amine Condensation Product Behavioral Alteration Electron Impact Mass Spectrum Psychosomatic Disorder
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- 6.Y.Makino, S.Ohta, Y.Tasaki, 0.Tachikawa, M.Kashiwasake and M.Hirobe, A novel and neurotoxic tetrahydroisoquinoline derivative in vivo: Formation of 1,3-dimethyl-1,2,3,4-tetrahydroisoquinoline, a condensation product of amphetamines, in brains of rats under chronic ethanol treatment, submitted for publication.Google Scholar