5-Hydroxytryptamine Oxygenase Regulator

Ternaux et al. (1979) found serum 5-hydroxytryptamine (5-HT) to be markedly decreased in Down syndrome whereas cerebrospinal fluid levels of 5-hydroxytryptamine and of 5-hydroxyindoleacetic acid were increased. It had generally been agreed that 5-HT is decreased in platelets in Down syndrome. Their measurements reflected this low platelet 5-HT. A gene on chromosome 21 that is important in the regulation of 5-HT metabolism may be indicated by these findings.