title: Photoperiod affects distribution of dynorphin A in the brain of Siberian hamster.
abstract: Dynorphin A1-77 (DYN A1-17) acting in the CNS is known to affect thermoregulation, water and energy balance in the short time scale. In this study a long-term alteration of these functions induced by changes of day length in the highly photoperiodic species, the Siberian hamster (Phodopus sungorus) was studied using immunohistochemistry for DYN A1-17. We found that in the long day (LD, L:D 16 h:8 h) more brain areas express DYN A1-17 peptide than in the short day (SD, L:D 8 h:16 h) conditions. Structures of the hypothalamo-pituitary axis as well as cells of the ependyma, subcomissural organ and choroid plexus of the lateral and third brain ventricles are immunoreactive to anti-dynorphin IgG only in the LD. This might indicate a seasonal regulatory role of DYN A1-17 in physiological adaptations to severe climate changes.
authors.affiliation: Department of Vertebrate Physiology, Faculty of Biology, Warsaw University, 1 Miecznikowa St., 02-096 Warsaw, Poland. k.meyza@nencki.gov.pl.
authors.forename: Ksenia Z
authors.initials: KZ
authors.lastname: Meyza
authors.forename: Jolanta
authors.initials: J
authors.lastname: Sotowska-Brochocka
mesh_terms: D000818:Animals; D001921:Brain / Q000378:metabolism*; D006224:Cricetinae; D004399:Dynorphins / Q000378:metabolism*; D005260:Female; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D017111:Phodopus / Q000378:metabolism*; D017440:Photoperiod; D013997:Time Factors
chemical_list: D004399:Dynorphins