Effects of low-dose leptin and gender on the physiology of the mouse (Mus musculus).
Exogenous leptin was given intraperitoneally to five male and five female mice at 0.2-0.3 mg/kg/day for 3 days. The plasma glucose and thyroxine concentrations as well as the hepatic and kidney enzyme activities were determined. The hepatic glycogen phosphorylase activity was suppressed by leptin treatment in the male mice. The other parameters were not significantly influenced by exogenous leptin, but there was a trend towards increased gluconeogenesis and glycogen storage due to leptin treatment. Enzyme activities of glucose and fat metabolism as well as the responses to leptin administration were sexually dimorphic. Discriminant analysis separated the control and the leptin-injected males and females to four distinct groups. Leptin seems to have minor but widespread effects on the energy metabolism of a nonmutant rodent. In nature, one function of leptin could be carbohydrate preservation.
Mustonen
A-M
AM
Department of Biology, University of Joensuu, Finland. ammusto@cc.joensuu.fi
Nieminen
P
P
Hyvärinen
H
H
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D016002:Discriminant Analysis; D004734:Energy Metabolism / Q000187:drug effects*; D005260:Female; D006003:Glycogen / Q000378:metabolism*; D024981:Glycogen Phosphorylase / Q000378:metabolism; D007274:Injections, Intraperitoneal / Q000662:veterinary; D007668:Kidney / Q000201:enzymology; D020738:Leptin / Q000008:administration & dosage / Q000502:physiology*; D008099:Liver / Q000201:enzymology; D008297:Male; D051379:Mice / Q000502:physiology*; D011897:Random Allocation; D012727:Sex Characteristics; D013974:Thyroxine / Q000097:blood
D001786:Blood Glucose; D020738:Leptin; D006003:Glycogen; D024981:Glycogen Phosphorylase; D013974:Thyroxine