摘要
目的探讨促甲状腺激素释放激素(TRH)对大鼠结肠平滑肌细胞膜瞬时外向钾电流(Ito)和延迟整流钾电流(Ik)的影响。方法酶解法急性分离单个大鼠结肠平滑肌细胞,运用膜片钳方法检测10、20、50、100μmol/L的TRH对结肠平滑肌细胞膜Ito和Ik的影响。结果 TRH浓度依赖性减少Ito(P<0.05),10、20、50、100μmol/L的TRH可使峰值Ito降低13.4%、28.0%、39.5%、53.4%,但Ik降低不明显(P>0.05)。结论 TRH阻滞大鼠结肠平滑肌细胞的瞬时外向钾电流,但不能降低延迟整流钾电流,TRH可能通过调节细胞的兴奋性对肠道动力产生影响。
Objective To investigate the effects of thyrotropin-releasing hormone on transient outward potassium currents （I_to） and delay rectifier potassium current（I_k） in rat colonic smooth muscle cells. Methods Single rat colonic smooth muscle cell was isolated by collagenase,then whole cell patch technique was used to record I_to and I_k. Results TRH inhibited I_to of rat colonic smooth muscle cells in concentration-dependent manners（P0.05）,10,20,50,100 μmol/L TRH decreased I_to by 13.4%,28.0%,39.5% and 53.4% respectively,but can＇t decrease I_k（P0.05）. Conclusion TRH depresses I_to but has no effect on I_k in rat colonic smooth muscle cells.These observations suggest that TRH could alter colonic motility by regulating excitability.
出处
《胃肠病学和肝病学杂志》
CAS
2012年第1期59-62,共4页
Chinese Journal of Gastroenterology and Hepatology
基金
国家自然科学基金资助项目(30871148)
关键词
促甲状腺激素释放激素
结肠平滑肌
瞬时外向钾电流
延迟整流钾电流
膜片钳
Thyrotropin-releasing hormone
Colonic smooth muscle
Transient outward potassium currents
Delayed rectifier potassium currents
Patch clamp
