The Shenfu The Protective Effect Of Ca2 + On Myocardial Ischemia-reperfusion Injury Of Katp Channel Relationship Experimental Research

Objective:To study the relation of the protective effects of Shenfu Injection on myocardial ischemia-reperfusion injury with Ca2+,KATP channel in order to provide experiment foundation for clinical therapy of ischemic heart disease and myocardial preservation of extracorporeal circulation. Methods:The rat model of myocardial ischemia reperfusion injury was established by ligation of the left anterior descending coronary artery for 40 minutes and then reperfusion for 120 minutes in vivo.48 Sprague-Dawley rats were randomly divided into eight groups(n=6):group C(control group),group IR(ischemia-reperfusion group),group SFI(shenfu group),group SG(shenfu+glibenclamide),group G (glibenclamide group), group SB(shenfu+Bay k8644),group B(Bay k8644 group) , group D (Dimethyl Sulfoxide group).Before and after ligation of the left anterior descending coronary artery,rats were injected with NS,Shenfu Injection, Glibenclamide,Bay k8644 and Dimethyl Sulfoxide.The activity of superoxide dismutase(SOD),the content of malondialdehyde(MDA),TNF-a in myocardium,IL-6,cTnI in serum as well as the changes of myocardial ultrastructure were detected.In the meantime,the hemodynamic parameters were monitored by ALC-MPA Biological Signal Analysis System at different time points to determine if Shenfu Injection antagonize protective effects of Shenfu Injection on myocardial ischemia-reperfusion injury. Results:Compared with group C,LVSP,+dp/dtmax,-dp/dtmax and SOD decrease,but LVEDP,MDA,TNF-a,IL-6 and cTnI increase in every ligation group(P<0.05 or P<0.01).This states that ischemia-reperfusion is harmful to myocardium.Compared group SFI,group SG with group IR,Shenfu injection can improve myocardial stunning,increase LVSP,+dp/dtmax,-dp/dtmax,decrease LVEDP;raise the activity of SOD and decrease the content of MDA,increase myocardial ability of anti-oxidation, repress over-oxidative reaction of lipid,depress permeability of cell membrane, reduce release of inflammation medium and exudation of cTnI,protect myocardial ultrastructure(P<0.05 或 P<0.01).There was not significantly different among other ligation groups.These results prove that Shenfu injection has protective effects on myocardial ischemia reperfusion injury.These protective effects can be antagonized by Bay k8644,but can not be antagonized by glibenclamide and Dimethyl Sulfoxide. Conclusion:The protective effects of Shenfu injection on myocardial ischemia reperfusion injury was realized by repress openning of Ca2+ channel myocardial cell membrane,reduce in-flow of Ca2+,inhibit calcium overload,decress oxygen-derived free radidicals,suppress inflammation reaction.KATP channel cannot play an important role in the protective effects of Shenfu injection on myocardial ischemia reperfusion injury.