title: Effect of intermittent hypoxia on arcuate nucleus in the leptin-deficient rat.
abstract: Intermittent hypoxia (IH) is a major pathophysiological consequence of obstructive sleep apnea. Recently, it has been shown that IH results in changes in body energy balance, leptin secretion and concomitant alterations in arcuate nucleus (ARC). In this study, the role of leptin on these changes was investigated in leptin-deficient rats exposed to IH or normoxic control conditions. Body weights, consumatory and locomotor behaviours, and protein signaling in ARC were assessed immediately after IH exposure. Compared to normoxia, IH altered body weight, food intake, locomotor pattern, and the plasma concentration of leptin and angiotensin II in the wild-type rat. However, these changes were not observed in the leptin-deficient rat. Within ARC of wild-type animals, IH increased phosphorylated signal transducer and activator of transcription 3 and pro-opiomelanocortin protein expression, but not in the leptin-deficient rat. The long-form leptin receptor protein expression was not altered following IH in either rat strain. These data suggest that leptin is involved in mediating the alterations to body energy balance and ARC activity following IH.
authors.affiliation: Department of Physiology and Pharmacology, The University of Western Ontario, London N6A 5C1, Canada. Electronic address: john.ciriello@schulich.uwo.ca.
authors.forename: John
authors.initials: J
authors.lastname: Ciriello
authors.affiliation: Department of Physiology and Pharmacology, The University of Western Ontario, London N6A 5C1, Canada.
authors.forename: Jason M
authors.initials: JM
authors.lastname: Moreau
authors.affiliation: Sigma Advanced Genetic Engineering Labs, Sigma-Aldrich Corp., St. Louis, MO, USA.
authors.forename: Aaron
authors.initials: A
authors.lastname: McCoy
authors.affiliation: Department of Physiology and Pharmacology, The University of Western Ontario, London N6A 5C1, Canada; Department of Medicine, The University of Western Ontario, London N6A 5C1, Canada.
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Jones
mesh_terms: D000804:Angiotensin II / Q000097:blood; D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000378:metabolism*; D001835:Body Weight; D004326:Drinking; D004435:Eating; D000860:Hypoxia / Q000378:metabolism*; D020738:Leptin / Q000097:blood / Q000172:deficiency / Q000378:metabolism*; D008124:Locomotion; D008297:Male; D011333:Pro-Opiomelanocortin; D051381:Rats; D017207:Rats, Sprague-Dawley; D050796:STAT3 Transcription Factor / Q000378:metabolism
chemical_list: D020738:Leptin; D050796:STAT3 Transcription Factor; C494088:Stat3 protein, rat; D000804:Angiotensin II; D011333:Pro-Opiomelanocortin
keywords: Arcuate nucleus of the hypothalamus; Body energy balance; Intermittent hypoxia; Leptin; Pro-opiomelanocortin; Signal transducer and activator of transcription 3