The effect of leptin on the ventilatory responseto hyperoxia.
Leptin-deficient mice show a blunted response to hypercapnia explained by central nervous system effects. The impact of leptin on peripheral chemoreceptor function is unclear. Therefore, 9 mutant (ob/ob) and 9 wild-type (+/+) mice were exposed to room air or 100% oxygen and respiratory rate (RR) and tidal volume (Vt) were measured. Subsequently, ob/ob mice received either leptin or vehicle and measurements were repeated. Compared to baseline, for +/+ mice, RR decreased significantly by 9.4% +/- 3.0% (means +/- SD), whereas Vt remained unchanged. Transition from normoxia to hyperoxia did not change RR and Vt in untreated ob/ob mice, whereas after leptin treatment, RR and Vt decreased significantly. Leptin deficiency abolishes the response to hyperoxia, which is restored by leptin replacement. Thus, leptin seems to be influential for a competent peripheral chemoreceptor function.
Groeben
Harald
H
Department of Anesthesiology and Critical Care Medicine, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA. harald.groeben@uni-essen.de
Meier
Sascha
S
Brown
Robert H
RH
O'Donnell
Christopher P
CP
Mitzner
Wayne
W
Tankersley
Clarke G
CG
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D004435:Eating / Q000187:drug effects; D018496:Hyperoxia / Q000503:physiopathology*; D007274:Injections, Intraperitoneal; D020738:Leptin / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008820:Mice, Obese; D009765:Obesity / Q000503:physiopathology*; D010100:Oxygen / Q000494:pharmacology; D010993:Plethysmography, Whole Body; D015656:Respiratory Mechanics / Q000187:drug effects*
D020738:Leptin; D010100:Oxygen