哇巴因不敏感的钠离子对肾组织中镁离子依赖性ATP酶的刺激作用。

Ouabain-insensitive Na+ stimulation of an Mg-2+ -dependent ATPase in kidney tissue.

Proverbio F, Condrescu-Guidi M, Whittembury G

Biochim Biophys Acta. 1975 Jun 25;394(2):281-92. doi: 10.1016/0005-2736(75)90265-5.

Abstract

Freshly prepared microsomal fractions of the outermost cortex of guinea pig kidney show an Mg-2+-dependent ATPase activity which is partially inhibited by 100 mM NaCl, LiCl, KCl, RbCl, CsCl, NH4Cl or choline chloride. 2. If the microsomal preparation is aged by storage at 4 degrees C for 10-15 days, the Mg-2+-dependent activity shows stimulation by Na-+ and Li-+ but not by K-+, Rb-+, Cs-+, NH4-+ or choline. 3. Stimulation is similar with sodium salts of Cl-minus, HCO3-minus, CH3COO-minus, BR-minus, SO4-2-minus or methylsulphonate. 4. Stimulation is insensitive to 1 mM and 10 mM ouabain. 5. Stimulation is unaltered by the presence of 0.5 mM ethyleneglycol-bis-(beta-aminoethyl ether)N,N'-tetracetic acid. 6. Stimulation is 100% inhibited by 2 mM ethacrynic acid, a concentration which inhibits only 30% of the Mg-2+-dependent ATPase and 50% of the (Na-++K-+)-stimulated ATPase. 7. Some of these characteristics coincide with those of an ouabain-resistant, K-+-independent, ethacrynic acid-sensitive mode of Na-+ extrusion out of guinea pig kidney cortex cells.

摘要

豚鼠肾最外层皮质的新鲜制备微粒体部分显示出一种Mg²⁺依赖性ATP酶活性，该活性被100 mM氯化钠、氯化锂、氯化钾、氯化铷、氯化铯、氯化铵或氯化胆碱部分抑制。2. 如果微粒体制剂在4℃储存10 - 15天进行老化，Mg²⁺依赖性活性会受到Na⁺和Li⁺的刺激，但不受K⁺、Rb⁺、Cs⁺、NH₄⁺或胆碱的刺激。3. 用Cl⁻、HCO₃⁻、CH₃COO⁻、Br⁻、SO₄²⁻或甲磺酸盐的钠盐刺激效果相似。4. 刺激对1 mM和10 mM哇巴因不敏感。5. 0.5 mM乙二醇双（β - 氨基乙醚）N，N' - 四乙酸的存在不会改变刺激效果。6. 2 mM依他尼酸可100%抑制刺激，该浓度仅抑制30%的Mg²⁺依赖性ATP酶和50%的（Na⁺ + K⁺）刺激的ATP酶。7. 其中一些特征与豚鼠肾皮质细胞中一种对哇巴因耐药、不依赖K⁺、对依他尼酸敏感的Na⁺外排模式的特征相符。