5‐Hydroxytryptophol in Human Cerebrospinal Fluid: Conjugation, Concentration Gradient, Relationship to 5‐Hydroxyindoleacetic Acid, and Influence of Hereditary Factors

Abstract

The serotonin metabolite 5-hydroxyiryptophol was studied in human cerebrospinal fluid. A minor fraction (∼13%) was found in conjugated form from which it was liberated by treatment with sulphatase containing 3- glucuronidase activity. A concentration gradient of 5-hydroxytryptophol concentration was shown on lumbar tapping and the concentration in ventricular CSF was about 2.5 times higher than that in lumbar CSF. 5-Hydroxytryptophol and 5-hydroxyindoleacetic acid concentrations were significantly correlated in healthy, psychotic, and depressed subjects, but not in alcoholics. 5-Hydroxytryptophol concentrations in CSF of psychotic and depressed subjects were not different from those of healthy controls (4.22 pmol/ml ± 0.15, SEM). In healthy subjects, hereditary factors seemed to have little influence on the CSF level of 5-hydroxytryptophol.