Abstract: ObjectiveTo investigate the effects of sevoflurane anesthesia on cognitive function and the expression of acetylcholine in aged rats.MethodsSixty Sprague-Dawley rats were randomly divided into 3 groups:control group,1% sevoflurane group,and 2% sevoflurane group.All rats received anesthesia for 5 days.Cognitive function was tested with Morris water maze.Acetylcholine expression in the hippocampus was determined with enzyme-linked immunosorbent assay(ELISA).ResultsMorris water maze test demonstrated that both latency and the total distance for hidden-platform were significantly decreased in all groups,while the cognitive function in the sevoflurane groups was lower than that of the controls.The latency and total distance for the rats in 1% and 2% sevoflurance groups were significantly lower than those of the rats in the control group at day 4 and day 7 of the treatment(at day 4:F=11.10,F=17.47;at day 7:F=49.23,F=202.74;P<0.01 for all).The expression of acetylcholine in the hippocampus of the sevoflurane groups was significantly lower than that of control group(F=30.67 at day 4,F=24.38 at day 7;P<0.01 for all).ConclusionSevoflurane could impair cognitive function of aged rats through inhibiting the expression of acetylcholine in the hippocampus.