Abnormal Ca and Na pump of cultured vascular smooth muscle cells from hypostensive rats.

为了阐明膜对阳离子通透性的异常以及体液因素在高血压发病机制中的差异性，用培养细胞研究了自发性高血压大鼠(SHR)血管平滑肌细胞的钙、钠转运动力学及血清对这些转运的影响。与WKY相比，SHR的VSMC明显激活了钙和钠泵。这种差异可能是由于SHR VSMC的Na-H逆向转运增加所致。在SHR血清存在的情况下，Na-Pump被激活，这种刺激最初是由Na-H反式激活所触发的。这些证据有力地表明，不仅SHR细胞固有的细胞膜通透性异常增加，而且一些未知的体液因素也参与其中，从而引起Na-Pump的激活，继而激活Na-H反式连接。

To elineate abnormalities in membrane permeability to cations as well as differential characteristic of humoral factors in the etiology of hypertension, Ca and Na transpport kinetics of vascular smooth muscle cells and the effect of serum from spontaneously hypertensive rats (SHR) on these transports were addressed using culture cells.A substantial activation in both Ca and Na pump was observed in VSMC of SHR compared to that of WKY. This difference may be caused by an increased Na-H antiport of SHR VSMC. In the presence of serum from SHR, there was a greater stimulation of Na-pump, which was originally triggered by the actiation of Na-H antiport.These evidences strongly suggest not only an abnormally increased membrane permeability of SHR cell membrane which is innate to SHR cells but also the involvement of some unknown humoral factors which elicits an activation of Na-pump followed by an activation of NA-H antiport.