Effect of splenectomy on spatial learning and memory in rats / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effect of acute injury caused by surgery on spatial learning and memory and the underlying mechanism. Methods Ninty-eight healthy SD rats of both sexes weighing 300-350 g were randomly divided into 3 groups (A) control group received neither anesthesia nor surgery ( n = 14); (B) anesthesia group received intraperitoneal fentanyl 0.2 mg?kg-1 and droperidol 5 mg?kg-1 only ( n = 42) and ( C) splenectomy group received splenectomy under fentanyl and droperidol anesthesia ( n = 42) . Y-maze test was performed to assess the ability of spatial learning and memory in group A and on the 1 st, 3 rd and 7 th day after anesthesia or surgery in group B and C. Seven rats were killed immediately after Y-maze test in group A and on the 1 st, 3 rd and 7 th day after anesthesia (in group B) and surgery (in group C) , and hippocampus was immediately removed for determination of the expression of TNF-? and IL-1? mRNA (RT-PCR) and protein (Western blot). Results The voltage of electric stimulation was significantly higher in group C on the 1st day after surgery than in group B on the 1st day after anesthesia and in group A. The time spent to learn and remember in Y-maze test was significantly longer in group C on the 3 rd than in group B on the 3 rd day and in group A. The expression of TNF-? mRNA and IL-1? mRNA and protein was significantly higher in group C than in group B on the 1st day and in group A.Conclusion Splenectomy can impair the spatial learning ability for a short time after surgery. The increase in the expression of TNF-? mRNA and IL-1? mRNA and protein in hippocampus may play a role in the mechanism.