锌对红细胞膜ATP酶活性影响的研究

从体内和体外 2方面研究锌对红细胞膜 Na+ ,K+ - ATP酶和 Ca2 + ,Mg2 + - ATP酶活性的影响。健康雄性 Wistar大鼠分别喂饲低锌、常量锌和高锌饲料 (饲料锌含量分别为 2 .2、2 8、12 8mg/kg) ,2 5天后各组随机取 8只动物腹主动脉取血后处死 ,测定血清锌含量和红细胞膜 Na+ ,K+ - ATP酶和 Ca2 + ,Mg2 + - ATP酶活性 ;各组剩余 6只动物改变其锌摄入量后继续喂饲 7天后 ,观察锌对红细胞膜 2种 ATP酶活性影响的敏感性。体外实验用新鲜制备的人红细胞膜 ,在不同浓度锌 (0、5、10、5 0、10 0和 5 0 0 μmol/L)溶液中温浴 ,观察 2种 ATP酶活性的变化趋势。结果表明 ,锌对红细胞膜的 2种 ATP酶活性均有影响 ,锌浓度过低或过高可抑制酶活性。与 Na+ ,K+ - ATP酶相比 ,Ca2 + ,Mg2 + - ATP酶对缺锌更敏感且补锌后不易恢复 ,但其对高锌有较强的耐受性。本次研究结果提示锌对于维持红细胞膜 ATP酶的正常活性有重要意义。

Effect of zinc on theactivities of ATPase of erythrocyte membrane

The effects of zinc on the activities of Na+, K(+)-ATPase and Ca2+, Mg(2+)-ATPase of erythrocyte membrane were studied both in vivo and in vitro. Male adult rats were divided into three groups and fed on diets with different concentration of zinc (2.2, 28 and 128 mg/kg diet). Eight rats of each group were sacrificed after 25 days and the activities of the two ATPase were measured. The rest rats were changed diet for an other seven days to detect the sensitivities of the ATPases. The activities of these ATPase were also determined in fresh human erythrocyte membrane treated with different concentration of zinc (0, 5, 10, 50, 100, 500 mumol/L). The results showed that the activities of both Na+, K(+)-ATPase and Ca2+, Mg(2+)-ATPase were in close relationship with zinc concentration, too low or too high zinc could decrease them. Compared with Na+, K(+)-ATPase, Ca2+, Mg(2+)-ATPase was more sensitive to zinc deficiency and in a slower reaction to zinc supplement, but it could stand higher zinc concentration. It was concluded that zinc played an important role on maintaining the normal activities of Na+, K(+)-ATPase and Ca2+, Mg(2+)-ATPase.