文档介绍：
牛磺酸镁抗缺氧/复氧致大鼠心肌细胞瞬时
外向钾离子通道异常的研究#
李宏杰,尹永强,张铭慧,康毅,娄建石**
5
10
15
(天津医科大学基础医学院,天津市 300070)
摘要:目的研究牛磺酸镁配合物(taurine magnesium pound,)对缺氧/
复氧损伤所致大鼠心肌细胞异常瞬时外向钾电流(Ito)的影响,以探讨其抗心律失常作用
机制。方法采用 Langendoff 逆行主动脉灌注酶消化法急性分离大鼠单个心室肌细胞,应用
全细胞膜片钳技术记录不同浓度及胺碘酮对大鼠单个心室肌细胞缺氧/复氧模型 Ito
的影响。结果与正常组相比,缺氧/复氧大鼠心室肌细胞 Ito 峰值由 ± pA/pF 增大
至 ± pA/pF(n=6,P<),I-V 曲线上移;(200μ mol/L,400μ mol/L)和胺
碘酮 mol/L 均可使因缺氧/复氧损伤增大的 Ito 减小,使 I-V 曲线下移。与正常组相
比,缺氧/复氧使 Ito 激活曲线左移,对失活曲线无影响,(200μ mol/L,400μ mol/L),
mol/L 胺碘酮可恢复左移的激活曲线。结论可通过抑制钾通道的激活过程对
抗复缺氧/复氧引起的 Ito 增大,提示该作用可能是抗缺氧复氧诱发心律失常的作用
机制之一。
关键词:电生理学;牛磺酸镁;心律失常;胺碘酮;瞬时外向钾离子通道;全细胞膜片钳
中图分类号:R961
20
Effect of Taurine Magnesium pound on
abnormal Transient Outward Potassium Current induced
by Hypoxia/Reoxygenation in Cardiomyocytes of rat
LI Hongjie, YIN Yongqiang, ZHANG Minghui, KANG Yi, LOU Jianshi
25
30
35
40
(Basic Medical School,Tianjin Medical University,Tianjin 300070)
Abstract: AIM To clarify the antiarrhythmic mechanism of taurine magnesium coordination
compound(), we observed the effect of on abnormal Transient Outward Potassium
Current (Ito) induced by hypoxia/reoxygenation in rat venticular cardiomyocytes . METHODS
Enzymatic dissociation was used to get single rat ventricular myocytes and whole-cell patch clamp
was used to record Ito in ventricular cardiomyocytes suffered from hypoxia/reoxygenation in rat
under amiodarone and at different concentrations. RESULTS In
hypoxia/reoxygenation model,peak Ito increased from (±) pA/pF to (±) pA/pF
(n=6,P<). 200 μmol/L, 400 μmol/L and amiodarone μmol/L restored peak Ito.
The I-V curve of Ito upward shift induced by hypoxia/reoxygenation were inhibited by and
amiodarone. Compared to control group ,hypoxia/reoxygenation shifted Ito steady-state activation
curves to the left which made activation of potassium channel quickly. 200 μmol/L,400
μmol/L and amiodarone μmol/Lrestored the left-shifted activation p