The Delayed Protection About Electroacupuncture Pretreatment On Rabbit’s Myocardial Ischemia Reperfusion Injury And The Mechanism Study Based On Heat Shock Protein From Multi-family

Object:To explore the molecular biology basis of the theory on disease prevention and health protection of acupuncture pretreatment and to study the mechanism of delayed protection about electroacupuncture pretreatment on rabbit’s myocardial ischemia reperfusion injury by observing the prevention effects, the contents of CK in rabbit’s blood, the expression of important intermediary material in myocardial protection (PKC)、effect material (HSP27mRNA、HSP70mRNA、HSP90mRNA) and the proteins of death receptor pathway in cell apoptosis(Fas/FasL)Methods:New Zealand big ear white rabbits were randomly allocated to sham operation(sham), ischemia reperfusion(IR) and electroacupuncture pretreatment (EP) groups,setting three phase(0h、24h、48h). The animal model of rabbits with myocardial ischemia reperfusion injury was established by improved method.The electroacupuncture pretreatment at acupoints Neiguan was used as the test factor.The pathological morphology changes in ischemia tissue of left ventricular were observed under the light microscope. The ultrastructure changes in ischemia tissue of left ventricular were observed under the electron microscope.The contents of CK in blood serum were detected by ELISA. The expressions of PKC in myocardial tissue were detected by Western Blot. The gene expressions of HSP from multi-family (HSP27mRNA、 HSP70mRNA. HSP90mRNA) in myocardial tissue were detected by RT-PCR. The apoptotic index of myocardium were detected by TUNEL. The expressions of Fas/FasL in myocardial tissue were detected by immunohistochemistry.Results:(1)After modeled, the morphology change of myocardial tissue in IR group rabbit is most obvious,those in sham group is most light, the concentration of serum CK is statistically different in three phase between the two groups (P<0.05or P<0.01), indicating the molding’s success; the myocardial tissue morphology in EP group is obviously improved than those in IR group, and its serum CK concentration has significant difference with IR group in24h and48h (P<0.05), but those in two phase (24、48h) have no significant difference (P>0.05)..(2) Compared with sham group, the expression of PKC was obviously increased in IR group (P<0.05); similarly compared with sham group,those in EP group increased more significantly (P<0.01), and higher than those in IR group (P<0.05).(3) Compared with sham group, the expression of HSP70mRNA was obviously increased in IR group (P<0.05); similarly compared with sham group,those in EP group increased more significantly (P<0.01), and higher than those in IR group (P<0.05), the change trend of HSP70mRNA in each group was completely consistent with those of PKC. The change trend of HSP27mRNA and HSP90mRNA was similar with HSP70mRNA, but had no statistical support (P>0.05)..(4) Compared with sham group, the apoptosis index of myocardial cell in IR group increased significantly (P<0.01); And compared with IR group,those in EP group dropped significantly (P<0.05)..(5)Compared with sham group, the expression of Fas/FasL in IR group was significantly increased (P<0.05); And compared with IR group,those in EP group dropped significantly (P<0.05). Conclusion:(1) The improved methods of making rabbit model on myocardial ischemia reperfusion injury is effective and feasible, and can guarantee the need of research..(2)Electroacupuncture pretreatment can obviously improve the morphology of rabbit myocardial tissue in ischemia reperfusion injury, can reduce the concentration of serum CK in24h and48h,showing good delayed protection.(3)With the stimulus quantity setted in this research set, electroacupuncture pretreatment can not induce a fast phase protection.(4) Electroacupuncture pretreatment can further the activation of PKC improved by ischemia reperfusion injury in delayed time, and can effectively induce the expression of HSP70mRNA.Activating"PKC phosphorylation-HSP70" is the key step of electroacupuncture starting delayed protection.(5)In multi-family of HSP,HSP70has specific response with electroacupunc-ture pretreatment.(6)In delayed time,electroacupuncture pretreatment can inhibit myocardial cell apoptosis in ischemia reperfusion injury, and can down-regulate the expression of death receptor pathway Fas/FasL system. Down-regulating "Fas/FasL-cell apoptosis" is the important way of electroacupuncture pretreatment realizing delayed protection.