Objective:To explore the effects of angiotens in Ⅳ on the hippocampus neuronal apoptosis and the cognitive function of diabetic rats.Methods:38 SD male rats were divided into normal group

diabetic model group and angiotensin Ⅳ treatment group randomly.Streptozotocin-diabetic rat model was established and learning and memory behaviors were investigated using a spatial version of the Morris water maze test.The expression of Bcl-xl of all rats was examined with immunohistochemical method.Meanwhile

the hippocampal neuronal apoptosis were measured by TUNEL.Results:Learning and memory grade in the angiotensin Ⅳ treatment group were better than diabetic model group(P<0.05).The changes of Bcl-xl in hippocampus significantly increased in the angiotensin Ⅳ treatment group and the number of apoptotic neurons of the hippocampus was decreased remarkably(P<0.05).Conclusion:Angiotensin Ⅳ could improve cognitive ability in diabetic rats by increasing the expression of Bcl-xl to protect hippocampus neuronal apoptosis.