title: Hyperserotonemia and amine metabolites in autistic and retarded children.
abstract: Mean whole blood serotonin (5-HT) levels were elevated in groups of autistic and severely retarded children. Eight of 27 (30%) individual autistic children, 13 of 25 (52%) severely retarded children, two of 23 (9%) mildly retarded children, and none of the control children had statistically significant blood 5-HT levels elevations (hyperserotonemia). Hyperserotonemic autistic children excreted more urinary 5-HT, 5-hydroxyindoleacetic acid (5-HIAA), tryptamine, and vanillylmandelic acid than did mildly retarded children with normal blood 5-HT levels. Rates of depletion and repletion of blood 5-HT levels in these two groups following reserpine therapy were identical. Oral tryptophan administration doubled urinary 5-HIAA excretion in both groups and raised urinary 5-HT levels in hyperserotonemic autistic children, but lowered urinary 5-HT in mildly retarded, normal blood 5-HT children. No clear mechanism for hyperserotonemia was found; the rationale for further investigations is discussed.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001321:Autistic Disorder / Q000097:blood / Q000378:metabolism* / Q000652:urine; D002648:Child; D002674:Child, Institutionalized; D002675:Child, Preschool; D006801:Humans; D006897:Hydroxyindoleacetic Acid / Q000652:urine*; D008607:Intellectual Disability / Q000097:blood / Q000378:metabolism* / Q000652:urine; D007360:Intelligence; D009043:Motor Activity; D012110:Reserpine / Q000494:pharmacology; D012701:Serotonin / Q000097:blood* / Q000652:urine; D014363:Tryptamines / Q000652:urine; D014364:Tryptophan / Q000494:pharmacology; D014642:Vanilmandelic Acid / Q000652:urine
chemical_list: D014363:Tryptamines; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D014642:Vanilmandelic Acid; D012110:Reserpine; D014364:Tryptophan