<b>TETRAHYDROISOQUINOLINE AND 1-METHYL-TETRAHYDROISOQUINOLINE ARE PRESENT IN THE HUMAN BRAIN: RELATION TO PARKINSON’S </b><b>DISEASE </b>

Abstract

1,2,3,4-Tetrahydroisoquinoline (TIQ) and 1-methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ) were detected in two regions (frontal lobe and caudate nucleus) of eight human brains, four from the control and four from patients with parkinsonism. The TIQ content did not significantly differ between control and parkinsonian brains in both regions. In contrast, the 1MeTIQ content was markedly reduced in the parkinsonian brain, particularly in the frontal lobe, suggesting an important role of this amine in parkinsonism.