The Effect of Ischemic Postconditioning on the Notch1 Signaling Pathway and Learning and Memory in Rats with Cerebral Ischemia Reperfusion Injury / 中国医科大学学报

ABSTRACT

Objective To assess the effect of ischemic postconditioning on the Notch1 signaling pathway,and learning and memory in rats with global cerebral ischemia.Methods A total of 128 healthy male SD rats were randomly divided into the sham operation (sham),whole-brain ischemia(CIR),ischemic treatment(CIP),and inhibitor(DAPT) groups,with 32 rats in each group.A global cerebral ischemia model was generated using the modified Pulsinelli's four-vascular occlusion model,and the inhibitor group was injected intraperitoneally with gamma secretase inhibitors (DAPT) before ischemic treatment.Rats' learning and memory function results from the Morris water maze test were assessed by observing the changes in hippocampal CA1 neurons with HE staining.The expression of Notch1 in the CA1 area of the hippocampus was assessed using immunohistochemical and Western blotting methods in rats.Results Compared with the sham group,the hippocampal cell survival rate in the CIR group decreased significantly (P ＜ 0.05) and the expression level of Notch1 increased significantly (P ＜ 0.05).Compared with the CIR group,the CIP group revealed a significantly higher hippocampal cell survival rate (P ＜ 0.05) and an increase in Notch 1 expression (P ＜ 0.05);compared with the CIP group,the hippocampal cell survival rate significantly decreased after DAPT administration (P ＜ 0.05) and Notch1 expression decreased significantly.Conclusion Ischemic postconditioning can promote the recovery of learning and memory ability,which may relate to the activation of the Notch 1 signaling pathway.