Neurochemical Control of Circadian Rhythms
Abstract
We have continued our investigation of the neurochemical systems contained in the circadian clock localized within the suprachiasmatic nucleus (SCN). Our primary focus has been to determine the circadian functions of a subpopulation of SCN interneurons in which vasoactive intestinal peptide (VIP), peptide histidine isoleucine (PHI) and gastrin releasing peptide (GRP) have been co-localized. In these studies we have demonstrated: 1) VIP/PHI neurons are found in the ventrolateral SCN where photic projections terminate, 2) a rhythm of VIP/PHI mRNA within the SCN that correlates with day-night cycle, 3) a modulation of SCN content of VIP and PHI by environmental lighting, 4) combined microinjection of VIP/PHI/GRP into the SCN mimics the phase delay of circadian rhythms produced by light, and 5) VIP/PHI/GRP alters the electrical activity of SCN single units. In other studies we have investigated the possible circadian functions of arginine vasopressin, GABA and neuropeptide Y (NPY) within the SCN, and the role of NPY within the para-ventricular nucleus on corticosterone secretion. Keywords: Hypothalamus, Gene expression.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 20, 1989
- Accession Number
- ADA206213
Entities
People
- Albers H. Elliott
Organizations
- Georgia State University