Sakamoto K
Second Department of Internal Medicine, Faculty of Medicine, Kagoshima University.
Fukuoka Igaku Zasshi. 1991 Nov;82(11):562-75.
To clarify the pathogenesis of essential hypertension (EHT), the biophysical property (fluidity) and Na(+)-K+ ATPase activity of the erythrocyte membrane were pursued. Seventeen patients with EHT, 14 normotensives (NT) with familial history of hypertension and 25 healthy controls (CONTROL) without familial history of hypertension were subjected in this study. Electron spin resonance (ESR) method using 5- or 16-stearic acid label (SAL) was used to measure the membrane fluidity of erythrocytes. Since little changes in the Na(+)-K+ ATPase activity may be expected, the bioluminescence method was adopted to measure the enzyme activity. By evaluation of several measuring conditions for the enzyme activity, the method was revealed to be highly sensitive and reproducible, as has been reported by Lechi. A significant decrease was found in the erythrocyte membrane fluidity of EHT patients using 16-SAL with the parameter of peak height ratio (ho/h-1), when compared with that of CONTROL (EHT: 5.31 +/- 0.13;
5.20 +/- 0.11, p less than 0.05). The decrease of erythrocyte membrane fluidity, values of peak height ratio using 16-SAL, correlated significantly with the systolic blood pressure (r = 0.36 p less than 0.05) and diastolic pressure (r = 0.34 p less than 0.05). The values of peak height ratio of NT (5.26 +/- 0.17) were found in between those of EHT and CONTROL. The levels of erythrocyte membrane Na(+)-K+ ATPase activity in EHT showed higher than those of CONTROL, but the difference was not significant. They did not correlate with the membrane fluidity and the blood pressure. The artificial modifications of membrane cholesterol contents of erythrocytes made the same directional changes in both the membrane fluidity and the enzyme activity. The results showed that the abnormality of biophysical property existed in the deeper portion of the erythrocyte membrane and indicated the possibility of hereditary perpetuation of EHT. As to changes in Na(+)-K+ ATPase activity, no definite contributory relation to EHT has been identified.
为阐明原发性高血压（EHT）的发病机制，对红细胞膜的生物物理特性（流动性）和钠钾ATP酶活性进行了研究。本研究纳入了17例EHT患者、14例有高血压家族史的血压正常者（NT）以及25例无高血压家族史的健康对照者（CONTROL）。采用5-或16-硬脂酸标记（SAL）的电子自旋共振（ESR）方法测量红细胞膜流动性。由于预计钠钾ATP酶活性变化不大，因此采用生物发光法测量酶活性。通过对酶活性的几种测量条件进行评估，结果显示该方法具有高度敏感性和可重复性，正如莱奇所报道的那样。与CONTROL组相比，使用16-SAL并以峰高比（ho/h-1）为参数时，EHT患者的红细胞膜流动性显著降低（EHT：5.31±0.13；CONTROL：5.20±0.11，p＜0.05）。红细胞膜流动性的降低，即使用16-SAL时的峰高比值，与收缩压（r = 0.36，p＜0.05）和舒张压（r = 0.34，p＜0.05）显著相关。NT组的峰高比值（5.26±0.17）介于EHT组和CONTROL组之间。EHT组红细胞膜钠钾ATP酶活性水平高于CONTROL组，但差异不显著。它们与膜流动性和血压均无相关性。对红细胞膜胆固醇含量进行人工改变后，膜流动性和酶活性出现了相同方向的变化。结果表明，红细胞膜深层存在生物物理特性异常，提示EHT可能存在遗传延续性。关于钠钾ATP酶活性的变化，尚未确定其与EHT有明确的因果关系。
