原发性高血压患者红细胞膜胰岛素受体与钙、镁代谢的关系

目的　探讨原发性高血压 (EH)患者钙、镁离子代谢与红细胞膜胰岛素受体 (EIR)之间的联系及在胰岛素抵抗中的作用。方法　观察 47例EH病人及 30例正常对照红细胞内Ca2 +、Mg2 +含量 ,2 4h尿Ca2 +、Mg2 +排泄量 ,红细胞膜Ca2 +,Mg2 + ATP酶和Na+,K+ ATP酶的活性变化。结果　①EH组患者胰岛素敏感指数 (ISI)、红细胞内Mg2 +含量、2 4h尿Mg2 +排泄量、EIR的低亲合位点数 (RT2 )、Ca2 +,Mg2 + ATP酶和Na+,K+ ATP酶活性减低。红细胞内Ca2 +含量、EIR的解离常数KD2 增高 (P <0 .0 5 )。②EH组ISI与RT2 、红细胞内Mg2 +含量呈正相关 ;RT2 与红细胞内Mg2 +含量、2 4h尿Ca2 +、Mg2 +排泄量呈正相关。③以RT2 为应变量 ,红细胞内Mg2 +含量 (X1 )、2 4h尿Ca2 +(X2 )、2 4h尿Mg2 +排泄量 (X3)为自变量的多元线性逐步回归分析中 ,X1 、X2 进入方程。结论　钙、镁代谢障碍可能是EH胰岛素抵抗时红细胞膜胰岛素低亲和受体水平下调的主要因素。

Relationship between calcium, magnesium metabolism and erythrocyte insulin receptor in insulin resistance with essential hypertension

Objective To examine the relationship between calcium, magnesium metabolism and erythrocyte insulin receptor (EIR) in insulin resistance (IR) in patients with essential hypertension (EH). 77 subjects were studied (47 hypertension and 30 normotension) the levels of the Mg 2+ ,Ca 2+ in erythrocyte, 24 hour urinary excretion of Mg 2+ ,Ca 2+ , erythrocyte membrane Na +,K + ATPase and Ca 2+ ,Mg 2+ ATPase, and EIR.Results ① Among the patients of the hypertension group, insulin sensitivity index [ISI=In (1/fast glucose × fast insulin)],the levels of Mg 2+ in erythrocytes,erythrocyte membrane Na +,K + ATPase and Ca 2+ ,Mg 2+ ATPase,low insulin affinity binding site of EIR (RT 2) were found to be remarkably lower, but the low dissociation constants of EIR( KD 2) and the levels of erythrocyte Ca 2+ were noted to be significantly higher;②In the hypertension group,the ISI was positively correlated with RT 2 and the levels of Mg 2+ in erythrocytes. The RT 2 was positively correlated with the levels of Mg 2+ in red blood cells, and also the 24 hour urinary excretion of Mg 2+ , Ca 2+ ;③A multiple linear stepwise regression analysis was used with ISI as the dependent variable.The levels of Mg 2+ in erythrocytes ( X 1 ), 24 hour urinary excretion of Ca 2+ ( X 2 ) and Mg 2+ ( X 3 ) as independent variables, and X 1, X 2 were used in equations.Conclusion Regulation down insulin low affinity receptors might play an important role in pathogenesis of IR with EH and correlates to magnesium and calcium metabolism.