有家族史的原发性高血压患者细胞钠转运与血浆内源性类地高辛物质浓度的改变

Changes of transmembrane Na^+ transport and plasma endogenous digoxin-like substances in essential hypertensives with a family history

目的 :探讨原发性高血压 ( EH)遗传因素对 Na+转运及内源性类地高辛物质 ( EDLS)浓度的影响 ,了解 Na+敏感性高血压的发病机制。方法 :5 2例 EH患者 ,分为有家族史组 ( FH+组 ,2 3例 )和无家族史组 ( FH-组 ,2 9例 ) ,2 5例健康人作对照组。血浆 EDL S浓度、EDLS与红细胞结合率( RBC- D% )采用放射免疫分析法 ;细胞内 Na+浓度 (〔 Na+〕i)用火焰光度法测定 ;红细胞哇巴因敏感钠外流速度常数 ( o Kos· h-1) ,测定加哇巴因后 2 h细胞内〔 Na+〕i,计算出 o Kos,o Kos反映总的 Na+泵活性。红细胞 Na+/ H+交换最大速率 ( Na+/ H+Vmax) ,测定不同外向 H+浓度梯度时的 Na+内流 ,计算出 Na+/ H+Vmax。结果 :FH+组和 FH-组血浆 EDLS、红细胞 Na+/ H+交换均高于对照组 ,o Kos和 RBC- D%结合率均低于对照组 ;FH+组 Na+泵活性、血浆 EDL S高于 FH-组。在 FH+组中 ,RBC-D%与 EDLS呈负相关。结论 :遗传与 EH的 Na+泵 Ouabain抵抗有关。EDLS与膜亲合能力下降影响离子转运而参与遗传性高血压的发病机制。

Objective:To investigate the effects of heredity on Na + transmembrane transport and endogenous digoxin like substances (EDLS) concentration in essential hypertension (EH) and it′s role in the development of Na + sensitive hypertension.Method:52 essential hypertensives were divided into two groups,23 with positive family history (FH +) and 29 with negative family history (FH -).The rate of 125 Ⅰ digoxin binding to red blood cells (RBC D%) and EDLS were measured with radioimmunoassay,the rate constant of ouabain sensitive sodium efflux ( oK os ·h -1 ) was measured as half the increase in erythrocyte Na + concentration during incubation with ouabain 2 h, oK os was calculated by equation,the maximal rate (V max ) of red cells Na +/H + exchange was determined as the Na + influx promoted by an outward H + gradient then calculated,and intracellular Na + concentration was measured with flame photometry and compared between three groups.Result: The ouabain sensitive Na + efflux and RBC D% were significantly lower but the levels of plasma EDLS,red cell Na +/H + exchange were significantly higher in both FH + and FH - groups than in controls.FH + group demonstrated a significant higher plasma EDLS and ouabain sensitive Na + efflux compared with those in FH - group.The cell Na + concentration was not significantly different among three groups.RBC D% was negatively correlated with EDLS and with Na +/H + exchange in FH + group.Conclusion:This data show a genetic contribution to Na + sensitivity in hypertension.The lower affinity of EDLS for membrane may affect transmembrane ion transport which participate in the pathogenesis of inherited hypertension.