Indole(ethyl)amine N-Methyltransferase in Human Brain

TANIMUKAI et al.¹, using gas-liquid separation, correlated the appearance of a bufotenin-like substance in urine and the onset of psychosis in latent schizophrenics brought on by administration of a monoamine oxidase inhibitor with amino-acid precursors of indoleamines and methyl groups. Serious doubt about endogenous bufotenin as the cause of psychiatric disturbance was cast by research demonstrating that intravenously administered bufotenin produced nothing but bizarre cardiovascular symptoms in man^{2, 3}. One objection to such work is that bufotenin may not easily cross the blood-brain barrier. Recent preliminary evidence gathered in our laboratories from rats infused intraventricularly with bufotenin has suggested that this substance is at least as potent as its powerfully hallucinogenic 5-methoxy congener (unpublished results of D. Segal and A. J. M.).