In vitro half-life of 14-C-tryptamine in whole blood of drug-free chronic schizophrenic patients.

The authors found higher in vitro 14C-tryptamine half-lives in the blood of 10 drug-free chronic schizophrenic patients than in the blood of 13 mentally normal control subjects. This finding was negatively correlated for both groups with platelet MAO activity. Repeated determinations of in vitro 14C-tryptamine half-lives over a period of 5 months were positively correlated for the patients, although some blood samples showed statistically significant variability.