心肌细胞的钾通道电流是复杂的,具有多样性,如果按整流现象来分类,大致可分为两大类:(1)外向整流电流,例如瞬时外向钾电流(I_(to):I_(to1)、I_(to2))与延迟整流钾电流(I_k:、I_(kr)、I_(KS)、I_(kp))。(2)内向整流钾通道电流,例如:内向整流 K~+电流(I_(k1))、ATP 敏感的 K~+电流(I_(K-ATP))和 ACh 激活的 K~+电流(I_(K-ACh))。一般说,内向整流K~+电流(I_(k1))主要调节静息电位,而外向整流钾通道电流主要控制动作电位时程。 The potassium channel currents of cardiomyocytes are complex and diverse. If they are classified by rectification, they can be broadly divided into two categories: (1) outward rectified currents, such as the instantaneous outward potassium current (Ito ), I_ (to2)) and delayed rectifier potassium current (I_k:, I_ (kr), I_ (KS), I_ (kp)). (2) Inwardly rectified potassium channel currents, such as inward rectified K ~ + current (I_ (k1)), ATP-sensitive K_ + current (K_ATP) and ACh activated K ~ + current K-ACh)). In general, the inward rectified K ~ + current (I_ (k1)) mainly adjusts the rest potential, while the outward rectified K + channel current mainly controls the action potential duration.