Our current program consists of both basic and clinical components. Our basic work consists of studies on the regulation of synthesis and degradation of neurotransmitter enzymes; regulation of the production and turnover of S-adenosylmethionine and related enzymes; genetic determination of dopamine and serotonin receptors; solubilization, isolation and purification of a high-affinity [3H]serotonin binding site; molecular biology studies cloning genes for catecholamin enzymes and neurotransmitter receptors; and neurochemical studies in canine narcolepsy. Our clinical studies are related to the major psychiatric disorders of childhood, specifically infantile autism, childhood schizophrenia, and depression. We are conducting three collaborative projects with autistic, schizophrenic and retarded children. These are studies determining biochemical mechanisms of hyperserotonemia in autistic and retarded children; studies on opiate peptides and pain responses in autistic children, and a large multicenter trial of fenfluramine administration to autistic children. In addition, we conduct collaborative biochemical studies with the Stanford Mental Health Clinical Research Center exploring neurotransmitter levels and neurotransmitter receptor concentration in unipolar, bipolar and schizophrenic patients. We intend to continue our work in these project areas. Emphasis will be placed on the molecular biology studies, the continued purification of a high-affinity serotonin receptor, and the descriptive genetics of dopamine and serotonin receptors. In our studies in autistic children, emphasis will be placed on elaborating biochemical mechanisms of hyperserotonemia.