A cerebral decarboxylase for 5-hydroxytryptophane in humans

¹ Research Facility, Rockland State Hospital, Orangeburg, New York

Little or no cerebral decarboxylation of 5-hydroxytryptophane could be found using the in vivo technique developed in this laboratory for determination of human cerebral metabolism. Following intravenous injection of dl-5-hydroxytryptophanecarboxyl-C¹⁴ little or no significant venous-arterial C¹⁴O₂ differences resulted in four normal control subjects and four chronic mental patients. No significant differences were found between the two groups. Levels of arterial blood C¹⁴O₂ activities showed that 5-hydroxytryptophane was decarboxylated readily by other body tissues. Of four subjects pretreated with 1-benzyl-2-methyl-5-methoxytryptamine (BAS), slightly lowered results occurred with the mental patient pretreated with a double dose of BAS.