Methyl Prednisolone Deep Hypothermic Cerebral Ischemia And Reperfusion In Rats The Effects Of The S-100 Protein Research

[Background] :Techniques of deep hypothermic circulatory arrest (DHCA) and deep hypothermic low flow (DHLF ) have been widely applied in cardiac surgery, but it's temporarily or permanent complications were high to 4% 25% (average 8%), and safe time of operation only 45 60 minutes, which limited its clinical application. Presently, some studies showed that complications of DHCA are correlated to ischemia and reperfusion. To detect the influence of Methylprednisolone on S-100 beta protein after deep hypothermia cerebral ischemia reperfusion in rats , the model of deep hypothermia cerebral ischemia reperfusion had been established with SD rats, and ELISA ,HE, immunohistochemistry (SABC) and RT-PCR had been used. [Methods]: part Ⅰ: To establish the model of deep hypothermia cerebral ischemia reperfusion : 25 SD rats were used in the experiment, artery press through artery spile in femoral artery, electrocardiograph, temperature, blood saturation of O₂ (SaO₂) and arterial blood gas were monitored during the whole experiment, blood flow of bilateral common carotid artery of rats were occluded about 60 minute when its temperature was reduced to 21℃ by ice, then normal temperature were resumed.Part Ⅱ: Effect of MP on serum S-100 beta protein after DHIR in rats: One hundred and twenty rats were divided randomly into three groups: Pseudo operational group (n=8); Methylprednisolone(MP) treatment group included the post ischemia reperfusion 2h,6h,12h,1d,2d,3d,7d sub groups (each sub group n=8); Model group contained the post ischemia reperfusion 2h,6h,12h, 1d,2d,3d,7d sub groups (each sub group n=8)。 Model of DHIR were prepared by 60mins occlusion followed reperfusion of bilateral common carotid artery in deep hypothermia (21 ℃). We measured serum S-100β protein level in different time points with ELISA.Part Ⅲ: Effect of MP on expression of S-100β protein in brain tissue. Detected expressions of S-100β protein with immunohistochemistry.Part Ⅳ: Effect of MP on expression of S-100mRNA in brain tissue. Detected expressions of S-100mRNA with technique of RT-PCR, and measured relative values of PCR products.