论文部分内容阅读
目的:研究未成年人心房肌细胞瞬间外向钾电流(I_(to))和内向整流钾电流(I_(Kl))的特性。方法:膜片箝全细胞技术。结果:I_(to)是电压依赖性电流,快速激活,快速失活,被I_(to)的选择性阻断剂4-AP阻断。IC_(50)=0.64mmol·L~(-1)。4-AP1mmol·L~(-1)使I_(to)的半数激活电位增加;4-AP0.3mmol·L~(-1)使I_(to)的半数失活电位减少,对激活曲线没有明显影响并使I_(to)的恢复时间延长。I_(Kl)也表现出电压依赖的特性,其反转电位在-40mV。结论:在未成年人心房肌细胞上,I_(to)和I_(Kl)是两种重要的K~+通道电流。4-AP0.3mmol·L~(-1)时对I_(to)的失活和失活后的恢复有明显影响,1mmol·L~(-1)时影响I_(to)的激活。
Objective: To study the characteristics of transient outward potassium currents (I_ (to)) and inwardly rectifying potassium currents (I_ (Kl)) in minors’ atrial myocytes. Methods: patch clamp whole cell technology. RESULTS: Ito is a voltage-dependent current that rapidly activates and rapidly inactivates and is blocked by 4-AP, a selective I-toxin blocker. IC 50 = 0.64 mmol·L -1. 4-AP1mmol·L -1 increased the half activation potential of I_ (to); 4-AP0.3mmol·L -1 decreased the half number of I_ (in) inactivation potential but had no obvious effect on the activation curve Affect and extend I_ (to) recovery time. I_ (Kl) also exhibits a voltage-dependent characteristic with an inversion potential of -40 mV. Conclusion: I_ (to) and I_ (Kl) are two important K ~ + channel currents in minors atrial myocytes. 4-AP 0.3 mmol·L -1 significantly affected the inactivation and inactivation of I-to after inactivation, while 1 mmol·L -1 affected the activation of I-to.