尼群地平对自发性高血压大鼠红细胞膜钙结合力和红细胞内总钙含量的作用(英文)

Effects of nitrendipine on capacity of calcium binding of erythrocyte membrane and total intraerythrocyte calcium content in SHR rats

目的:研究尼群地平(Nit)对自发性高血压大鼠红细胞膜钙结合力和红细胞内总钙含量的作用。方法:应用尾套法测清醒大鼠收缩压,按改良Bing氏法制备红细胞膜,用原子吸收光谱法检测红细胞膜钙结合力及红细胞内总钙量。结果:尼群地平(ig 10mg·kg^(-1) qd×20d)能显著降低自发性高血压大鼠红细胞内总钙含量(169±18vs 87±14μmol/L cell,P<0.01),同时使收缩压明显下降(27.1±2.5vs 16.7±1.0 kPa,P<0.01),但对CaCl_2 0mmol·L^(-1)的基础膜钙结合力及CaCl_2 40mmol·L^(-1)的最大膜钙结合力均无影响。结论:Nit的抗高血压作用可能与其降低细胞内钙含量有关,而与细胞膜钙结合力没有直接关系。

AIM: To study the effect of nitrendipine (Nit) on the capacity of calcium binding of erythrocyte membrane and total intraerythrocyte calcium content in spontaneous hypertensive rats (SHR). METHODS: Systolic blood pressure (SBP) of the consciouse rats was monitored by tailcuff method with a BP and HR recorder for MRS-1 rat. Erythrocyte membrane was prepared according to modified Bing's method. Calcium binding of membrane and total intraerythrocyte calcium content was determined by an automatic absorption spectrophotometer. The membrane protein was determined with a colorimetric methed. RESULTS: Nit (ig 10 mg·kg-1 qd X20 d) induced a significant reduction in total intraerythrocyte calcium content (169±18 vs 87±14 μmol/L cell, P < 0. 01) accompanied by a marked fall of SBP (27. 1±2. 5 vs 16. 7±1. 0 kPa, P<0. 01) but exerted no influence on the capacity of calcium binding of erythrocyte membrane under incubation in CaCl20 (basal calcium binding) or 40 mmol·L-1 (maximal calcium binding) (21. 9±2. 3 vs 22.7 ±2.1 and 55±14 vs 53±23 μmol/g protein, respectively, P>0. 05). CONCLUSION: The an-tihypertensive effect of Nit is related to the reduction of intracellular calcium and possibly have no direct relation to the capacity of calcium binding of cell membrane.