title: Short day lengths decrease body mass of overweight female meadow voles.
abstract: Groups of adult ovariectomized (ovx) voles and sham-ovx controls were placed in a short photoperiod or left in the original long photoperiod (10 or 14 hr light/day). In the next 12 weeks long-day ovx voles increased their body mass by 11.3%, whereas animals transferred to the short-day photoperiod manifested an 11.9% decline in body mass. Short photoperiods not only reversed pre-existing weight gains attributable to ovariectomy, but also prevented further increases in body mass associated with the withdrawal of ovarian hormones. Fat-free dry carcass mass was increased by ovariectomy and decreased by short photoperiods; lipoprotein lipase activity of white adipose tissue was unaffected by ovariectomy or photoperiod. We suggest that reductions in body mass in voles transferred to the short photoperiod are mediated by changes in pineal melatonin secretion.
mesh_terms: D000273:Adipose Tissue / Q000201:enzymology; D000818:Animals; D003411:Arvicolinae / Q000378:metabolism*; D001823:Body Composition; D001835:Body Weight; D005247:Feeding Behavior / Q000502:physiology; D005260:Female; D008027:Light; D008071:Lipoprotein Lipase / Q000378:metabolism; D010052:Ovariectomy; D010507:Periodicity
chemical_list: D008071:Lipoprotein Lipase