Effects of mimic ischemic preconditioning on hyperpolarizaion-activated current of cultured sinoatrial node cells of neonatal rat
- VernacularTitle:模拟缺血预适应对原代培养乳鼠窦房结细胞起搏离子流的影响
- Author:
Qian ZHANG
;
Shifei TONG
;
Ji HUANG
;
Zhiyuan SONG
- Publication Type:Journal Article
- Keywords:
sinoatrial node cell;
ischemic preconditioning;
patch clamp;
hyperpolarization-activated current
- From:Journal of Third Military Medical University
1983;0(04):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the effects of stimulated ischemic preconditioning (IP) and ischemia/reperfusion (I/R) on the hyperpolarization-activated current (I_ f ) of sinoatrial node cells and explore the mechanisms of electrophysiological protection of IP. Methods The sinoatrial node cells cultured for 2 d were randomized to three groups: ① Control in which the cells were cultured at 37 ℃ in the mimic reperfusion solution, meanwhile the mixture of 95% O_ 2 and 5% N_ 2 was ventilated; ② I/R in which the cells were cultured in the mimic ischemic solution and simultaneously the mixture of 95% O_ 2 and 5% N_ 2 was ventilated for 3 h, then cultured in the mimic reperfusion solution and simultaneously the mixture of 95% O_ 2 and 5% N_ 2 was ventilated for 4 h; ③ IP in which the cells underwent ischemia for 10 min and reperfusion for 10 min, repeated once. Then the cells were treated as the same as the I/R group. After 4-hour reperfusion, I_ f was recorded by whole-cell patch clamp technology. Results I/R significantly enhanced the current density of I_ f , shifted the current activation curve to more positive value by changing the half-activation voltage from (-98.9?2.4) mV to (-85.2?2.5) mV (P
