title: Intracerebroventricular administration of leptin increase physical activity but has no effect on thermogenesis in cold-acclimated rats.
abstract: Most small homotherms display low leptin level in response to chronic cold exposure. Cold-induced hypoleptinemia was proved to induce hyperphagia. However, it is still not clear whether hypoleptinemia regulates energy expenditure in cold condition. We try to answer this question in chronic cold-acclimated rats. Results showed that 5-day intracerebroventricular(ICV) infusion of leptin (5 μg/day) had no effects on basal and adaptive thermogenesis and uncoupling protein 1 expression. Physical activity was increased by leptin treatment. We further determined whether ghrelin could reverse the increasing effect of leptin on physical activity. Coadministration of ghrelin (1.2 μg/day) completely reversed the effect of leptin on physical activity. Collectively, this study indicated the regulation of leptin on energy expenditure during cold acclimation may be mainly mediated by physical activity but not by thermogenesis. Our study outlined behavioral role of leptin during the adaptation to cold, which adds some new knowledge to promote our understanding of cold-induced metabolic adaptation.
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang, Beijing 100101, China.
authors.forename: Gang-Bin
authors.initials: GB
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, 2 Yuanmingyuan West Road, Haidian, Beijing 100193, China.
authors.forename: Xiang-Fang
authors.initials: XF
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, 2 Yuanmingyuan West Road, Haidian, Beijing 100193, China.
authors.forename: Kui
authors.initials: K
authors.lastname: Li
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang, Beijing 100101, China.
authors.forename: De-Hua
authors.initials: DH
authors.lastname: Wang
mesh_terms: D000064:Acclimatization / Q000187:drug effects / Q000502:physiology; D000818:Animals; D001831:Body Temperature / Q000187:drug effects / Q000502:physiology; D001833:Body Temperature Regulation / Q000187:drug effects*; D003080:Cold Temperature; D004734:Energy Metabolism / Q000187:drug effects; D054439:Ghrelin / Q000008:administration & dosage / Q000494:pharmacology*; D057967:Infusions, Intraventricular; D020738:Leptin / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D022722:Thermogenesis / Q000187:drug effects*
chemical_list: D054439:Ghrelin; D020738:Leptin