Accession Number : ADA295080

Title :   Molecular Approach to Hypothalamic Rhythms.

Descriptive Note : Final rept. 15 Mar 92-14 Mar 95,

Corporate Author : SCRIPPS RESEARCH INST LA JOLLA CA

Personal Author(s) : Sutcliffe, J. G.

PDF Url : ADA295080

Report Date : 14 MAR 1995

Pagination or Media Count : 13

Abstract : The suprachiasmatic nucleus (SCN) of the hypothalamus is the anatomical seat or the mammalian endogenous biological clock which regulates the temporal expression of hormonal and behavioral circadian rhythms. Light, serotonin and melatonin are the dominant stimuli that affect the phase of the endogenous clock. The grantee has devised strategies to identify molecules that mediate the action of these stimuli within the SCN. The grantee has identified a novel receptor for serotonin, the 5-HT7 receptor, and determined its aminoacid structure. Its pharmacological ligand binding properties ahve been measured and a unique profile of agonists and antagonists defined. These allowed demonstration that the 5-HT7 receptor mediated circadian activity of cultured SCN. The receptor has been shown to couple to activation on adenylyl cyclase and to be synthesized by neurons of the subparaventricular zone immediately dorsal to the SCN. Molecules whose expression within the sCN is activated by light entraining cues have also been identified and their characterization is under way.

Descriptors :   *CIRCADIAN RHYTHMS, *HYPOTHALAMUS, SYNTHESIS, MOLECULES, LIGANDS, NERVE CELLS, SEROTONIN, BEHAVIOR, STIMULI, ANATOMY, PHARMACOLOGY, SEATS, MELATONIN.

Subject Categories : Anatomy and Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE