Relationship between level of AMP-activated protein kinase in hippocampus and cognitive dysfunction after splenectomy in aged rats

Objective To evaluate the relationship between the level of AMP-activated protein kinase (AMPK) in hippocampus and cognitive dysfunction after splenectomy in aged rats.Methods Sixty-three male aged Sprague-Dawley rats,weighing 480-550 g,were randomly divided into 3 groups (n =21 each):control group (group C),anesthesia group (group A),and surgery group (group S).Morris water maze (MWM) test was performed to evaluate the spatial learning and memory ability before surgery and at 1,3 and 7 days after surgery.The escape latency and swimming distance were recorded.Seven rats were chosen after MWM test was performed at 1,3 and 7 days after surgery and sacrificed.Their hippocampi were removed for detection of the expression of AMPK and phosphorylated (p-AMPK) (by Western blot).Results Compared with the baseline,the escape latency and swimming distance were significantly prolonged at 1 and 3 days after surgery in group S (P ＜ 0.05).Compared with group C,the escape latency and swimming distance were significantly prolonged at 1 and 3 days after surgery,the expression of AMPK was up-regulated at 1,3 and 7 days after surgery,and the expression of p-AMPK was up-regulated at 1 and 3 days after surgery in group S (P ＜ 0.05),and no significant changes were found in the indices mentioned above in group A (P ＞ 0.05).Conclusion Increased AMPK level in hippocampus is the regulatory mechanism of the body adapting to the development of cognitive dysfunction after splenectomy in aged rats. Key words: Protein-serine-threonine kinases;  Cognition disorders;  Postoperative complications; Aged ;  Hippocampus