[Na+ + K+] ATP-ase in liver and brain of obese mice.
The activity of hepatic [Na+ + K+]ATP-ase showed a gene-dosage relationship in 6 week old mice. Before weaning hepatic [Na+ + K+]ATP-ase activity was normal in preobese mice but fell within 7 days of weaning to the low levels observed in older ob/ob mice. Brain [Na+ + K+]ATP-ase activity was unchanged in ob/ob mice although [3H]-ouabain binding was reduced. Arrhenius plots of [Na+ + K+]ATP-ase activity in liver and brain and of [3H]-ouabain binding to brain preparations showed breakpoints at lower temperatures in ob/ob than lean mice. These breakpoints were altered by pretreatment of tissue with deoxycholate. It is suggested that changes in membrane lipid composition might be an important factor regulating [Na+ + K+]ATP-ase in ob/ob mice.
D000367:Age Factors; D000818:Animals; D001921:Brain / Q000201:enzymology*; D003840:Deoxycholic Acid / Q000494:pharmacology; D008099:Liver / Q000201:enzymology*; D008297:Male; D051379:Mice; D008820:Mice, Obese; D009765:Obesity / Q000201:enzymology*; D010042:Ouabain / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013696:Temperature
D003840:Deoxycholic Acid; D010042:Ouabain; D000254:Sodium-Potassium-Exchanging ATPase