Molecular Approach to Hypothalamic Rhythms
Annual rept. 15 Mar 1993-14 Mar 1994
SCRIPPS RESEARCH INST LA JOLLA CA
Pagination or Media Count:
The suprachiasmatic nucleus SCN of the hypothalamus is the anatomical seat of the mammalian endogenous biological clock which regulates the temporal expression of hormonal and behavioral circadian rhythms. Light, serotonin and melatonin are the dominant stimuli which 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 amino acid structure. Its pharmacological ligand binding properties have 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 of 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.
- Anatomy and Physiology
- Medicine and Medical Research