title: Circadian rhythms of vasopressin content in the suprachiasmatic nucleus of the rat.
abstract: The suprachiasmatic nucleus (SCN) of the anterior hypothalamus contains a circadian pacemaker in mammals. We determined the circadian profiles of arginine-vasopressin (AVP), a major peptide in the dorsomedial SCN, in rats under light-dark (LD), constant dark (DD) and constant light (LL) conditions. Under LD conditions, AVP levels in the SCN showed circadian rhythmicity with a peak at early light phase and a broad trough during the dark phase. This rhythm in the AVP contents was maintained even after 14 days of free-running under DD conditions and 3 days under LL conditions. These circadian patterns of AVP are similar to those of somatostatin, another peptide in the dorsomedial SCN. This indicates a common mode of regulation for peptides in this subfield of the SCN.
authors.affiliation: Laboratory of Integrative Brain Functions, Mitsubishi Kasei Institute of Life Sciences, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tominaga
authors.forename: K
authors.initials: K
authors.lastname: Shinohara
authors.forename: Y
authors.initials: Y
authors.lastname: Otori
authors.forename: C
authors.initials: C
authors.lastname: Fukuhara
authors.forename: S T
authors.initials: ST
authors.lastname: Inouye
mesh_terms: D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism*; D002940:Circadian Rhythm / Q000502:physiology*; D007124:Immunoenzyme Techniques; D008297:Male; D017440:Photoperiod; D051381:Rats; D017208:Rats, Wistar; D013493:Suprachiasmatic Nucleus / Q000378:metabolism*
chemical_list: D001127:Arginine Vasopressin