Bindels R J, Geertsen J A, van Os C H
Clin Exp Hypertens A. 1985;7(12):1719-31. doi: 10.3109/10641968509073621.
A common abnormality of cellular Ca2+ handling in most tissues of spontaneously hypertensive rats (SHR) has been suggested. Therefore we investigated the ATP-dependent Ca2+ transport and Na+/Ca2+ exchange system in basolateral membrane vesicles (BLMV) of renal cortices from SHR and normotensive Wistar-Kyoto rats (WKY) at 12 and 20 weeks of age. In WKY the maximal transport rate of the ATP-dependent Ca2+ transport was 5.7 nmol/min/mg prot with an affinity for Ca2+ of 0.14 microM. These values were not significantly different in SHR at both ages studied. High concentrations of Na+ inhibited ATP-dependent Ca2+ uptake by 40% in BLMV of SHR and WKY. Low concentrations of Na+ stimulated ATP-dependent Ca2+ transport 20% in both rats. These findings suggest equal Na+/Ca2+ exchange activity in WKY and SHR. The present study failed to show a significant change in ATP-dependent Ca2+ transport and Na+/Ca2+ exchange activity in renal BLMV in SHR, suggesting that the Ca2+ homeostasis of the cortical cells is normal in SHR as far as the plasmamembrane is concerned.
研究表明，自发性高血压大鼠（SHR）多数组织中细胞钙处理存在常见异常。因此，我们研究了12周龄和20周龄SHR以及血压正常的Wistar-Kyoto大鼠（WKY）肾皮质基底外侧膜囊泡（BLMV）中ATP依赖的钙转运和钠/钙交换系统。在WKY中，ATP依赖的钙转运最大速率为5.7 nmol/分钟/毫克蛋白，对钙的亲和力为0.14 microM。在研究的两个年龄段的SHR中，这些值均无显著差异。高浓度的钠抑制SHR和WKY的BLMV中ATP依赖的钙摄取40%。低浓度的钠刺激两种大鼠的ATP依赖的钙转运20%。这些发现表明WKY和SHR中钠/钙交换活性相当。本研究未能显示SHR肾BLMV中ATP依赖的钙转运和钠/钙交换活性有显著变化，这表明就质膜而言，SHR皮质细胞的钙稳态是正常的。
