Sheedlo H J, Siegel G J, Desmond T J, Ernst S A
Department of Neurology, University of Michigan, Ann Arbor 48109.
Neurochem Res. 1987 Dec;12(12):1081-6. doi: 10.1007/BF00971708.
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.
髓磷脂缺陷型颤抖小鼠（Shi/Shi）可能是评估脑（Na⁺+K⁺）-ATP酶浓度和组成对髓鞘膜形成依赖性的有用模型。通过差速离心和蔗糖梯度沉降对年龄匹配的对照（+/+）小鼠和颤抖（Shi/Shi）小鼠的脑微粒体膜进行分级分离。与+/+小鼠相比，未检测到Shi/Shi小鼠脑的全匀浆、高速和低速级分或梯度级分中（Na⁺+K⁺）-ATP酶比活性降低。此外，十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）和用针对小鼠脑（Na⁺+K⁺）-ATP酶的抗血清进行免疫印迹显示，+/+和Shi/Shi脑级分之间催化亚基组成没有显著差异。+/+小鼠和髓磷脂缺陷型Shi/Shi小鼠获得的相似结果表明，髓磷脂对全脑（Na⁺+K⁺）-ATP酶的贡献很小。
