番茄碱对人红细胞膜Na+-K+-ATPase活性影响的研究

以低渗法从新鲜健康人红细胞中制得膜Na^ -K^ -ATPase，研究了番茄碱(tomatine)X~人红细胞膜Na^ -K^ -ATPase活性的影响。实验结果表明，反应体系中的tomatine浓度低于1mmol／L时，对不依赖钙调蛋白(CAM)激活的Na^ -K^ -ATPase(称之为基本酶活)影响不大，浓度达1mmol／L时，该酶活性仍保持在95％左右；而在此浓度范围内，tomatine对依赖CaM的Na^ -K^ -ATPase有明显的抑制作用，其IC50值为0．16mmol／L．说明tomatine对膜酶Na^ -K^ -ATPase活性的影响可能是通过阻断CaM激活的途径而起作用，从而为进一步研究番茄碱的作用机制奠定了基础。

Effect of tomatine on for enythrocyte membrane Na+-K+-ATPase activity

Erythrocyte membrane Na~+-K~+-ATPase from healthy human blood is prepared by the method of Hypo-Osmosis.The effect of tomatine on the activity of Na~+-K~+-ATPase is studied.The results showed that at lower concentration of tomatine (below 1 mmol/L),it does not have strong effect on basal Na~+-K~+-ATPase.When the concentration of tomatine is 1 mmol/L,the activity of basal Na-K-ATPase still remains over 95%.However,within this concentration of tomatine,it can obviously inhibit CaM-stimulated Na~+-K~+-ATPase.The IC_(50) value of tomatine is adout 0.16 mmol/L.It is valuable to further explore the molecular mechanism on the affected tomatine.