(Na+ + K+)-adenosinetriphosphatase in the brain of Shiverer (Shi/Shi) mice.
The myelin-deficient Shiverer (Shi/Shi) mutant mouse may be a useful model in assessing the dependence of brain (Na+ + K+)-ATPase concentration and composition on myelin membrane formation. Brain microsomal membranes from age-matched control (+/+) and Shiverer (Shi/Shi) mice were fractionated by differential centrifugation and sucrose gradient sedimentation. No reduction in (Na+ + K+)-ATPase specific activity was measured in whole homogenates, high- and low-speed fractions or gradient fractions from brains of Shi/Shi mice as compared to those of +/+ mice. In addition, sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting with antisera specific for mouse brain (Na+ + K+)-ATPase revealed no significant difference in catalytic subunit composition between fractions of +/+ and Shi/Shi brains. The similar results obtained for both +/+ and myelin-deficient Shi/Shi mice suggest that myelin contributes little to total brain (Na+ + K+)-ATPase.
Sheedlo
H J
HJ
Department of Neurology, University of Michigan, Ann Arbor 48109.
Siegel
G J
GJ
Desmond
T J
TJ
Ernst
S A
SA
D000818:Animals; D001921:Brain / Q000201:enzymology*; D008297:Male; D051379:Mice; D008818:Mice, Neurologic Mutants / Q000378:metabolism*; D008861:Microsomes / Q000032:analysis; D000254:Sodium-Potassium-Exchanging ATPase / Q000032:analysis*; D013347:Subcellular Fractions
D000254:Sodium-Potassium-Exchanging ATPase