title: Analysis of the phase shifting effects of gastrin releasing peptide when microinjected into the suprachiasmatic region.
abstract: The role of gastrin releasing peptide (GRP) in phase shifting circadian rhythms was investigated. Microinjection of GRP into the suprachiasmatic region (SCN) region produced only small changes in the phase of free-running circadian activity rhythms in hamsters housed in constant darkness. However, co-administration of GRP with vasoactive intestinal peptide (VIP) and peptide histidine isoleucine (PHI) produced significantly larger phase delays than GRP alone. These data support the hypothesis that GRP interacts with VIP and PHI within the SCN to induce phase shifts of circadian rhythms.
authors.affiliation: Department of Biology, Georgia State University, Atlanta 30303, USA.
authors.forename: H E
authors.initials: HE
authors.lastname: Albers
authors.forename: C F
authors.initials: CF
authors.lastname: Gillespie
authors.forename: T O
authors.initials: TO
authors.lastname: Babagbemi
authors.forename: K L
authors.initials: KL
authors.lastname: Huhman
mesh_terms: D000818:Animals; D002940:Circadian Rhythm / Q000187:drug effects*; D006224:Cricetinae; D003624:Darkness; D019886:Gastrin-Releasing Peptide; D005755:Gastrins / Q000378:metabolism*; D008297:Male; D008647:Mesocricetus; D008845:Microinjections; D009478:Neuropeptide Y / Q000008:administration & dosage / Q000494:pharmacology; D010451:Peptide PHI / Q000494:pharmacology; D010455:Peptides / Q000008:administration & dosage / Q000494:pharmacology*; D013493:Suprachiasmatic Nucleus / Q000187:drug effects / Q000502:physiology*; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology
chemical_list: D005755:Gastrins; D009478:Neuropeptide Y; D010451:Peptide PHI; D010455:Peptides; D014660:Vasoactive Intestinal Peptide; D019886:Gastrin-Releasing Peptide