Role of hippocampal mTOR signaling pathways in cognitive dysfunction after splenectomy in aged rats / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the role of hippocampal mammalian target of rapamycin (mTOR) signaling pathways in the cognitive dysfunction after splenectomy in aged rats.Methods Sixtythree male Sprague-Dawley rats,aged 18 months,weighing 400-540 g,were randomly divided into 3 groups (n=21 each) using a random number tablecontrol group (group C),operation group (group O) and mTOR inhibitor rapamycin group (group M).Morris water maze test was performed to evaluate cognitive function before operation and at 1,3 and 7 days after operation.After the end of Morris water maze test carried out at 1,3 and 7 days after operation,7 rats selected randomly in each group were sacrificed,and the brains were removed for detection of the expression of mTOR and phosphorylated tau protein at Ser-396 site (pS396 tau) in hippocampal tissues by using Western blot.Results Compared with group C,the escape latency was significantly prolonged,the ratio of time spending in the target quadrant was decreased,and the expression of pS396 tau was up-regulated at 1 and 3 days after operation,and the expression of mTOR was up-regulated at each time points after operation in group O,and the escape latency was significantly prolonged,the ratio of time spending in the target quadrant was decreased,and the expression of mTOR and pS396 tau was up-regulated at 1 and 3 days after operation in group M.Compared with group O,the escape latency was significantly shorten,the ratio of time spending in the target quadrant was increased,and the expression of pS96 tau was down-regulated at 1 and 3 days after operation,and the expression of mTOR was down-regulated at each time point after operation in group M.Conclusion The hippocampal mTOR signaling pathways are involved in the development of cognitive dysfunction after splenectomy in aged rats.