A Novel Endogenous Amine, 1-Benzyl-1,2,3,4-Tetrahydroisoquinoline(1BnTIQ) in Parkinsonian CSF, and Its Toxicological Effect
Recently there have been many reports in which 1,2,3,4-tetrahydroisoquinoline (TIQ) derivatives may be related to the onset of Parkinson’s disease.1–12 In these reports, we have already confirmed that TIQ and 1-methyl-TIQ (1MeTIQ) were detected in the brains of mice, rats, and humans; and the 1MeTIQ content in the parkinsonian brain was decreased in comparison with that in a normal subject’s brain, though the TIQ content was not changed in between both brains.1,2,8,13 In addition, pretreatment with 1MeTIQ perfectly prevented mice treated with TIQ or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP) from bradykinesia, one of the characteristic symptoms in Parkinson’s disease. The slight difference in the structure between 1MeTIQ and TIQ, which is whether it has a methyl group at one position or not, induces a reverse effect (Figure 1).
KeywordsTyrosine Hydroxylase Mouse Brain Toxicological Effect Pole Test Chronic Ethanol Treatment
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