Lucio F J, Hendry B M, Ellory J C
University Laboratory of Physiology, Oxford.
Exp Physiol. 1991 May;76(3):437-43. doi: 10.1113/expphysiol.1991.sp003510.
Sodium pump function has been studied in human erythrocytes depleted of membrane cholesterol by incubation with phosphatidylcholine liposomes. The cells were sodium loaded by incubation in alkaline sodium phosphate and sodium pump activity was assessed by measurements of ouabain-sensitive 86Rb uptake at 37 degrees C. Cholesterol depletion had a biphasic effect; depletion by 5-25% increased sodium pump activity by a mean of 16.1% (S.D. 3.2%), whereas depletion by 35-50% decreased sodium pump activity by a mean of 14.8% (S.D. 3.8%). Cholesterol depletion had no reproducible effect on the ouabain-insensitive uptake of Rb. These results support the hypothesis that there may be an optimum membrane cholesterol content for sodium pump function.
通过与磷脂酰胆碱脂质体孵育，对耗尽膜胆固醇的人红细胞中的钠泵功能进行了研究。细胞在碱性磷酸钠中孵育以加载钠，然后通过测量37℃下哇巴因敏感的86Rb摄取来评估钠泵活性。胆固醇耗竭具有双相效应；5-25%的耗竭使钠泵活性平均增加16.1%（标准差3.2%），而35-50%的耗竭使钠泵活性平均降低14.8%（标准差3.8%）。胆固醇耗竭对哇巴因不敏感的Rb摄取没有可重复的影响。这些结果支持这样的假设，即钠泵功能可能存在一个最佳的膜胆固醇含量。
