Abant Izzet Baysal University, Faculty of Science and Art, Biology Department 14280 Golkoy, Bolu Turkey.
Duzce University, Faculty of Science and Arts, Biology Department 81620 Konuralp, Duzce Turkey.
Iran J Basic Med Sci. 2015 Feb;18(2):188-93.
Electrical inhomogeneity between ischemic and non ischemic myocardium is the basis of arrhythmia which occurs following coronary artery occlusion. The leakage of potassium from the ischemic region to the non ischemic region is very effective in the generation of these arrhythmias. The aim of this study is to research the effect of ATP-dependent potassium (KATP) channel blocker (glibenclamide) and opener (pinacidil) on ischemia induced arrhythmia in the presence of small and large infarct sizes.
In this study Sprague-Dawley male rats of 8-9 months of age were used. Ischemia was produced by the partial ligation of left coronary artery ramus descending (PL) for smaller infarct and complete ligation of this artery (CL) for larger infarct for 30 min. The arrhythmia score which was calculated from the duration and type of arrhythmia was significantly higher in animals which had a larger infarct area than the animals which had a smaller infarct.
Glibenclamide increased the rate of arrhythmia in animals having smaller infarct but not in animals having larger infarct. Pinacidil did not affect the occurrence of arrhythmia in either group. There was a significant difference in the infarct size and risk of infarct zone between animals which had small and large infarct sizes. The effect of glibenclamide and pinacidil on the arrhythmias differed depend on decrease of infarct size.
Glibenclamide is not effective to decrease ischemia induced arrhythmia in the presence of small and pinacidil in large ischemic zone.
缺血和非缺血心肌之间的电不均一是发生冠状动脉闭塞后心律失常的基础。钾从缺血区漏到非缺血区对这些心律失常的产生非常有效。本研究的目的是研究在小梗死和大梗死面积存在的情况下，三磷酸腺苷依赖性钾（KATP）通道阻滞剂（格列本脲）和开放剂（吡那地尔）对缺血诱导性心律失常的影响。
本研究使用 8-9 月龄雄性 Sprague-Dawley 大鼠。通过部分结扎左冠状动脉降支（PL）产生较小梗死，完全结扎该动脉（CL）产生较大梗死，缺血 30 分钟。从心律失常的持续时间和类型计算得出的心律失常评分在梗死面积较大的动物中明显高于梗死面积较小的动物。
格列本脲增加了较小梗死动物心律失常的发生率，但对较大梗死动物没有影响。吡那地尔对两组动物心律失常的发生均无影响。小梗死和大梗死动物之间存在梗死面积和梗死区风险的显著差异。格列本脲和吡那地尔对心律失常的影响因梗死面积的减少而不同。
格列本脲在小梗死区存在的情况下对缺血性心律失常没有作用，而吡那地尔在大缺血区也没有作用。
