摘要
目的研究雷诺嗪对室性心律失常大鼠模型心肌氧自由基代谢及心肌Cx43调控的影响。方法36只健康级成年雄性Wistar大鼠随机分为正常组、模型组、雷诺嗪组;3组大鼠3.5mL/kg10%水合氯醛腹腔注射麻醉,模型组、雷诺嗪组于大鼠舌下静脉注射1mL/kg0.002%乌头碱,正常组于大鼠舌下静脉注射等量0.9%氯化钠溶液;造模成功后,雷诺嗪组注射5mg/kg雷诺嗪;正常组、模型组注射等量0.9%氯化钠溶液;应用酶联免疫吸附法测定心肌组织超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)的活性和丙二醛(MDA)含量,并分别应用免疫组织化学法、逆转录聚合酶链反应(RT-PCR)法、蛋白质印迹(Westernblotting)法检测心肌组织缝隙连接蛋白43(Cx43)表达。结果与正常组[(79.12±10.55)U/mg、(18.47±3.15)U/mg、(4.58±1.09)U/mg、(1.35±0.27)nmol/mg]比较,模型组SOD、GSH/Px、CAT下降,MDA上升[(53.27±9.02)U/mg、(10.82±2.47)U/mg、(2.45±0.67)U/mg、(2.33±0.40)nmol/mg];而与模型组比较,雷诺嗪组SOD、GSH/Px、CAT均较显著上升,MDA显著下降[(69.78±10.22)U/mg、(14.66±3.15)U/mg、(3.20±1.15)U/mg、(1.70±0.15)nmol/mg](P<0.05);免疫组织化学试验可见正常组Cx43主要分布在心肌闰盘处,与心肌纤维走行呈垂直现象;而模型组Cx43则明显较正常组变少,且多分布在心肌侧面,与心肌纤维走行呈平行现象;而雷诺嗪组Cx43则较模型组明显上升,且此时可见部分Cx43分布在心肌闰盘处;模型组心肌组织Cx43mRNA、Cx43蛋白及磷酸化Cx43蛋白表达量(0.42±0.09、0.59±0.14、0.34±0.10)显著低于正常组(0.91±0.12、1.24±0.35、0.76±0.12),而雷诺嗪组Cx43mRNA、Cx43蛋白及磷酸化Cx43蛋白表达量(0.81±0.10、0.79±0.15、0.64±0.15)则较模型组显著上升。结论雷诺嗪可改善室性心律失常大鼠心肌氧自由基代谢,并能上调室性心律失常大鼠心肌组织Cx43mRNA、Cx43及磷酸化Cx43蛋白表达量。
Objective To study the effects of ranolazine on the metabolism of oxygen free radicals and regulation of Cx43 in cardiac muscles of rat models with ventricular arrhythmia.Methods Thirty-six healthy adult male Wistar rats were randomly divided into the normal group,the model group and the ranolazine group.All rats were anesthetized with intraperitoneal injection of 3.5 mL/kg of 10%chloral hydrate.Rats in the model group and the ranolazine group were treated with sublingual intravenous administration of 1 mL/kg of 0.002%aconitine.The normal group were injected with the same amount of normal saline in the sublingual vein.After successful modeling,the ranolazine group were injected with 5 mg/kg of ranolazine.The normal group and the model group were injected with the same volume of normal saline.The levels of SOD,GSH/Px,CAT and MDA in myocardial tissues were measured by enzyme-linked immunosorbent assay.The expression of Cx43 in myocardial tissues was detected by immunohistochemistry,RT-PCR and Western blotting.Results Compared with the normal group[(79.12±10.55)U/mg,(18.47±3.15)U/mg,(4.58±1.09)U/mg,(1.35±0.27)nmol/mg],SOD,GSH/Px and CAT were lower,and MDA was higher in the model group[(53.27±9.02)U/mg,(10.82±2.47)U/mg,(2.45±0.67)U/mg,(2.33±0.40)nmol/mg].SOD,GSH/Px and CAT in the ranolazine group were significantly higher than those in the model group,and MDA was significantly lower than the model group[(69.78±10.22)U/mg,(14.66±3.15)U/mg,(3.20±1.15)U/mg,(1.70±0.15)nmol/mg](P<0.05).Immunohistochemistry showed that Cx43 in the normal group was mainly distributed in the myocardial disc and was perpendicular to the myocardial fibers.Cx43 in the model group was significantly lower than that in the normal group and mostly distributed on the side of the myocardium,parallel to the myocardial fibers.Cx43 in the ranolazine group was significantly higher than that in the model group,and part of Cx43 was distributed in the myocardial disc.The expression levels of Cx43 mRNA,Cx43 protein and phosphorylated Cx43 protein
作者
祝存奎
戴婧
朱芳一
ZHU Cun-kui;DAI Jing;ZHU Fang-yi(Department of Arrhythmia,Qinghai Cardiovascular Specialist Hospital,Xining Qinghai 810012,China;Department of Laboratory,Qinghai Cardiovascular Specialist Hospital,Xining Qinghai 810012,China)
出处
《临床和实验医学杂志》
2020年第19期2021-2025,共5页
Journal of Clinical and Experimental Medicine
基金
青海省卫生系统科研重点课题(编号:2017-wjzd-13)。
