The Relationship between Neuronal Cell Apoptosis with P~(53) Protein Expression and Cognitive Disorder Following Global Ischemia and Reperfusion in the Elder Rats

Objective To investigate the effects of global ischemia and reperfusion, on the behavior of rats as well as neuronal cell apoptosis and P53 protein expression. Methods The acute global ischemia (15 min) model was produced by four-vessel occlusion in elder Sprague-Daewley rats. The rats were randomly divided into three groups, that is normal group, sham-operated group, and operated group, all animals were observed for behavior changes before decapitated at 1,6,12,24,48.72 h and 7 d after ischemia and reperfusion. The neuronal cell apoptosis were detected by TUNEL method, and immunohistochemistry to observe the expression of P53 protein in frontal lobe. Results The learning and memory ability of the rats were impaired after global ischemia and reperfusion at 72 h and 7 d. TUNEL staining showed that there are a few TUNEL-positive cell appearing at 24 h after ischemia and reperfusion, this expression was maximal at 72 h, and declined obviously at 7 d. Immunohistochemistry staining showed there are a few P53 protein expression at 24 h in the operated group. This expression was maximal in 48 h, a few of expression were observed at 7 d after ischemia. Conclusions The acute global ischemia and reperfusion impairs the learning and memory ability of the rats. The delayed neuronal death after global ischemia and reperfusion was apoptosis, P53 protein expression was increased following global ischemia and reperfusion. The relationship between the neuronal cell apoptosis and P53 protein expression was a positive correlation in a certain time following global ischemia and reperfusion, but holds a negative correlation with cognitive disorder.