大电导钙激活钾通道在高血压病中的研究进展

大电导钙激活钾通道（BKCa）是血管平滑肌细胞（VSMCs）上表达最丰富的钾通道，对维持VSMCs的膜电位及血管收缩和舒张的动态平衡具有重要的调节作用。BKCa通道的激活可使细胞膜发生超极化，从而抑制电压依赖性钙通道的激活和钙离子内流，导致平滑肌舒张。对高血压患者的观察和高血压动物模型的研究发现，高血压血管张力升高时平滑肌细胞膜表面钾离子和钙离子通道表达和功能均发生异常，因此，有人推测高血压是离子通道重构导致平滑肌细胞去极化的结果。本文主要综述近年来BKCa通道在高血压病中的研究进展。

Research progress of large conductance Ca2+-activated K+ channel in hypertension

Large conductance Ca2+-activated K+ (BKCa) channels are abundantly expressed in vascular smooth muscle cells (VSMCs). Activation of BKCa channels leads to hyperpolarization of the plasma membrane, closure of Ca2+ channels, reduced intracellular Ca2+ levels and eventually vasodilation. Therefore, BKCa channels play an important role in determining membrane potential and regulation of vascular tone. The elevated vascular tone observed in human hypertension and in several experimental models of hypertension points to abnormalities of the expression and function of Ca2+ and/or K+ channels in VSMCs. VSMCs are more depolarized as a consequence of the ‘ion channel remodeling’ that occurs during chronic hypertension. In this review, we will mainly focus on BKCa channels in VSMCs that are reported to be altered in hypertension.