论文部分内容阅读
磷脂酰肌醇-4,5-二磷酸(PIP2)是调节心肌各种内向整流钾通道(Kir)活动最基本的因素。PIP2与Kir通道氨基端和羧基端的多个氨基酸位点特异性结合,通过静电作用影响通道的空间构型和开放概率。PIP2与Kir通道亲和性的高低决定通道的开放水平。多种生理和病理过程可通过影响细胞膜上PIP2的含量,精细地控制Kir通道的活动水平,并改变通道对若干调控因素和对药物的的敏感性。
Phosphatidylinositol-4,5-diphosphate (PIP2) is the most fundamental factor that regulates various inward rectifier potassium channels (Kir) activity in the myocardium. Site-specific binding of PIP2 to amino acids at the amino- and carboxyterminal ends of Kir channels specifically affects the spatial configuration and openness of the channels by electrostatic interactions. PIP2 and Kir channel affinity determines the level of openness of the channel. Various physiological and pathological processes can finely control the activity level of Kir channel by affecting the content of PIP2 on the cell membrane and change the channel’s sensitivity to several regulatory factors and drugs.