异丙酚对人心房肌细胞瞬时外向整流钾电流的影响  

Effect of propofol on transient outward K＋ current in isolated human atrial myocytes

作　　者：邝素娟[1] 邓春玉[1] 刘宇斌[1] 饶芳[1] 王春晓[1] 单志新[1] 李晓红[1] 林秋雄[1] 杨敏[1] 吴书林[1] 余细勇[1] 

机构地区：[1]广东省人民医院医学研究中心广东省医学科学院广东省心血管病研究所,广州市510080

出　　处：《中华麻醉学杂志》2009年第10期885-888,共4页Chinese Journal of Anesthesiology

基　　金：基金项目：国家自然科学基金资助项目（30672077）;广东省医学科研基金资助项目（A2006002）;广东省科技计划资助项目（2006B36002023）

摘　　要：目的 探讨异丙酚对人心房肌细胞瞬时外向整流钾电流（Ⅰto）的影响。方法体外循环下行冠状动脉旁路移植术患者，术中于上腔静脉插管前取下右心耳组织，采用急性两步酶解法消化分离成单个心房肌细胞，室温下进行膜片钳全细胞模式记录Ⅰto记录不同浓度（25、50、100、150、200μmol／L）异丙酚在＋50mv钳制电压下Ⅰto的变化，并记录50μmol／L异丙酚对Ⅰto激活、失活、失活后再激活动力学的影响。结果与给药前相比，50、100、150、200μmol／L异丙酚呈浓度依赖性地抑制Ⅰto峰电流密度（P〈0．05）。给药前、后半数激活电压和斜率因子、半数失活电压和斜率因子、时间常数比较差异无统计学意义（P〉0．05）。结论异丙酚可呈浓度依赖性地抑制人心房肌细胞Ⅰto产生负性肌力作用，可能是其抗心律失常作用的重要机制之一。Objective To investigate the effect of propofol on transient outward K＋ current （Ⅰto） in isolated human atrial myocytes. Methods Atrial myocytes were enzymatically isolated from specimens of human atrial appendages obtained from patients undergoing coronary artery bypass grafting. Ito was recorded in voltageclamp mode using the patch-clamp technique at room temperature. Current signals were recorded with an Axopatch 200B amplifier using the Digidata 1322A-pClamp 9.0 data-acquisition system. Results Propofol decreased Ito in a concentration-dependent manner in human atrial myocytes. The current-voltage curve was significantly decreased. Propofol （25, 50, 100, 150 and 200 ,μmol/L） decreased Ito current density （9. 89 ± 0.03） % , （52.3B ±0. 14） % , （61.75 ± 0.12）%, （71.30 ± 0.13）% and （81.31 ± 0.11）% respectively. The Ⅰto activation curve, the inactivation curve and the recovery curve were not significantly affected. Conclusion Propofol significantly decreases Ito in human atrial myocytes in concentration-manners.

关 键 词：二异丙酚 肌细胞 心脏 钾通道 

分 类 号：R96[医药卫生—药理学]