兔急性心肌梗死后心室肌细胞L-钙离子通道电流的变化(PDF)
《心脏杂志》[ISSN:1009-7236/CN:61-1268/R]
- 期数:
- 2003年第2期
- 页码:
- 109-112
- 栏目:
- 实验研究
- 出版日期:
- 2003-03-01
文章信息/Info
- Title:
- Alteration of L-calcium current in ventricular myocytes from infarcted rabbit heart
- Author(s):
- DING Chao; HE Zhen-shan; QI Shu-ying; CUI Jun-yv; SHI Qiao; YANG Li; HU Li-ye
- Department of Cardiology,Bethune International Peace Hospital of PLA,Shijia zhuang,He bei 050082,China
- Keywords:
- myocardial infarction; calcium channels; myocardium; patch clamp
- 分类号:
- R541.7;R542.2
- DOI:
- -
- 文献标识码:
- A
- 摘要:
- 目的:研究急性心肌梗死(AMI)后心室肌细胞钙离子通道电流的变化。方法:采用结扎兔冠状动脉左前降支 的方法建立AMI动物模型,应用膜片钳全细胞记录方法,观察AMI后1周及2月心外膜梗死区心肌细胞L-钙通 道电流(ICa-L)的变化。结果:①梗死后1周组、2月组与对照组相比,I-V曲线上移。ICa-L 电流密度峰值(0mV时)的比 较显示:对照组为5.6±1.5pA/pf(n=10);梗死后1周组为3.5±0.9pA/pf(n=6),较对照组显著减小,P<0.05; 梗死后2月组为4.8±1.5pA/pf(n=11),较对照组减小,较梗死后1周组增大,但均无统计学差异,P>0.05。②梗 死后1周组、梗死后2月组与对照组相比,失活曲线明显左移(即向超极化方向移动),以梗死后1周组左移更加明 显。梗死后1周组半数失活电压(V0.5)为-26±7mV(n=6),与对照组(-13±4mV,n=8)比较相差显著,P< 0.05。梗死后2月组半数失活电压V0.5 为-21±6mV(n=8),与对照组比较无统计学差异,P>0.05。结论:AMI后 1周梗死区心室肌细胞ICa-L 下降、钙通道动力学发生变化,在AMI后2月这种电生理异常有恢复趋势。
- Abstract:
- AIM:To study the current density and function of L-calcium channel in cells from the epicardial border zone of the 1-week and 2-month infarcted rabbit hearts.METHODS:Rabbits were infarcted by ligation of the left anterior descending coronary artery,1 week(PMI-1wk)and 2 month(PMI-2mo) later,I Ca-L was recorded using whole cell patch-clamp techniques from infarcted heart and compared with the ICa-L from the noninfarcted heart(Con). RESULTS:Peak ICa-L current density (at0mV) was significantly reduced in PMI-1wk(3.5±0.9pA/pF,n=6) compared with Con group(5.6±1.5pA/pF,n=10),P<0.01.However,2 month after the occlusion,the peak ICa-L density in PMI-2 mo(4.8±1.5pA/pF,n=11) was not significantly different from that of the Con group,although there was slight reduction in it.V0.5 of the availability curve was shifted significantly in the hyperpolarizing direction in PMI-1wk(-26±7mV,n=6)compared with that of the Con group(-13±4mV,n=8),P<0.05.V0.5 was also shifted in the hyperpolarizing direction in PMI-2mo(-21±6mV,n=8)compared with that of the Con group, althoughth is shift was not significant,P> 0.05.CONCLUSION:ICa-L was reduced, and its kinetics was altered in myocytes of the infarcted zone.2 month after the occlusion, the depressed ICa-L returned to nearly normal,suggesting the presence of reverse remodeling.
参考文献/References
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备注/Memo
- 备注/Memo:
- 收稿日期：2002-3-25.
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