Effect of isoflurane anesthesia on expression of amyloid β protein in hippocampus in aged rats / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effect of isoflurane anesthesia on the expression of amyloid β protein (Aβ) in hippocampus in aged rats.Methods Sixty-one healthy male SD rats,aged 18-19 months,weighing 400-500 g,were randomly divided into 3 groupsisoflurane group (group Ⅰ,n =31),control group (groupⅡ,n =20),and blank group (group Ⅲ,n =10).Group Ⅰ inhaled 1.4％ isoflurane for 2 h,and cognitive function was assessed at 5 d before and 2 d after anesthesia by Morris water maze.Group Ⅱ received Morris water maze text only.Group Ⅲ received no treatment.Group Ⅰ was divided into 2 subgroups according to whether the cognitive impairment occurredcognitive impairment group (P subgroup) and no cognitive impairment group (NP subgroup).The animals were sacrificed immediately after the test.The hippocampus was isolated for determination of the levels of Aβ40 and Aβ42,β-secretase (BACE),insulin degrading enzyme (IDE)and neprilysin (NEP).Results There was no significant difference in the results of Morris water maze test before anesthesia among the 3 groups.There was no significant difference in the swimming velocity between group Ⅰ and group Ⅱ.The time of staying at the original platform quadrant was significantly shorter in P subgroup than in NP subgroup and Ⅱ group,and there was no significant difference in the time of staying at the original platform quadrant between NP subgroup and Ⅱ group.There was no significant difference in the levels of Aβ40 and Aβ42,BACE,NEP and IDE among the 5 groups,and between P subgroup and NP subgroup.Conclusion Isoflurane anesthesia has no effect on the expression of Aβ in the hippocampus,indicating that isoflurane-induced cognitive impairment is not related to Aβ pathway in aged rats.