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

为探讨高血压病中细胞膜阳离子通透性异常及体液因素的差异性，采用体外培养细胞，观察了自发性高血压大鼠（SHR）血管平滑肌细胞（VSMC）钙、钠转运动力学及SHR血清对钙、钠转运的影响。这种差异可能是由于SHR VSMC的Na-H逆向转运增加所致。在SHR血清存在下，Na-泵的激活增强，而Na-泵的激活最初是由Na-H反向转运体的激活引起的，这些证据有力地表明，SHR细胞膜通透性的异常增加不仅是SHR细胞固有的，而且还与某些未知的体液因素有关，这些体液因素激活了Na-泵，继而激活了Na-H反向转运体。

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.