title: Effects of food restriction on the hypothalamic prepro-orexin gene expression in genetically obese mice.
abstract: Orexins, which are identical to hypocretins, are novel hypothalamic orexigenic peptides. We examined the effects of food restriction on the expression of the prepro-orexin gene in control (C57Bl/6J) and genetically obese mice (ob/ob and db/db), using in situ hybridization histochemistry. Dry food was given 3 g/day to each obese mouse for 2 weeks. Food restriction caused a significant increase of the prepro-orexin gene expression in obese mice in comparison with ad libitum fed animals. Although the levels of the expression of the prepro-orexin gene in obese mice were significantly lower than those in C57Bl/6J mice during feeding ad libitum, food restriction caused an increase in the expression of the prepro-orexin gene in the hypothalamus of obese mice. The expression of the neuropeptide Y (NPY) gene was increased significantly in the arcuate nucleus of obese mice compared to that of control mice during feeding ad libitum. Food restriction for 2 weeks also caused a significant increase of the expression in the NPY gene in all groups. These results indicate that the hypothalamic prepro-orexin gene could be upregulated by food restriction without leptin signal in genetically obese mice.
authors.affiliation: Department of Physiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Y
authors.initials: Y
authors.lastname: Ueta
authors.forename: R
authors.initials: R
authors.lastname: Serino
authors.forename: M
authors.initials: M
authors.lastname: Nomura
authors.forename: I
authors.initials: I
authors.lastname: Shibuya
authors.forename: H
authors.initials: H
authors.lastname: Yamashita
mesh_terms: D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000166:cytology / Q000378:metabolism; D001786:Blood Glucose / Q000235:genetics / Q000378:metabolism; D001835:Body Weight / Q000502:physiology; D005508:Food Deprivation / Q000502:physiology*; D005786:Gene Expression Regulation / Q000502:physiology*; D007026:Hypothalamic Area, Lateral / Q000166:cytology / Q000378:metabolism; D007031:Hypothalamus / Q000166:cytology / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008820:Mice, Obese; D009478:Neuropeptide Y / Q000235:genetics / Q000378:metabolism; D009479:Neuropeptides; D000068797:Orexins; D011498:Protein Precursors / Q000235:genetics* / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D047908:Intracellular Signaling Peptides and Proteins; D009478:Neuropeptide Y; D009479:Neuropeptides; D000068797:Orexins; D011498:Protein Precursors; D012333:RNA, Messenger