七氟醚对幼年大鼠空间学习记忆功能及海马区胆碱能神经元活力的影响

目的探讨七氟醚对幼年大鼠空间学习记忆功能及海马区乙酰胆碱酯酶（acetylcholinesterase,AchE）活力、胆碱乙酰转移酶（choline acetyltransferase,ChAT）活力的影响。方法出生7dSD大鼠48只随机分为3组,各16只,吸入体积分数3%七氟醚2h和6h者分别为S1和S2组,不作任何处理者为C组。于出生后第16～20天行Morris水迷宫实验测试3组空间学习记忆功能;于吸入麻醉结束后次日（Ⅰ期）、水迷宫实验结束后次日（Ⅱ期）取大鼠海马组织,比色法测定AchE和ChAT活力。结果 S1组第2～4天和S2组第2～5天逃避潜伏期较C组延长（P〈0.05）,S2组第4～5天逃避潜伏期较S1组延长（P〈0.01）;S1和S2组Ⅰ期AchE活力较C组增加、ChAT活力较C组降低（P〈0.01）;S2组Ⅱ期AchE活力较C组及S1组增加（P〈0.05）,各组间ChAT活力比较差异无统计学意义（P〉0.05）。结论体积分数3%七氟醚通过增加海马AchE活力、降低ChAT活力而降低幼年大鼠空间学习记忆功能,吸入6h较吸入2h影响更明显。

Effect of sevoflurane anesthesia on spatial learning and memory function and hippocampus cholinergic neurone activity in infant rats

Objective To investigate the effect of sevoflurane anesthesia on spatial learning and memory function and hippocampus acetylcholinesterase（AchE） activity and choline acetyltransferase（ChAT） activity in infant rats.Methods Forty-eight SD rats aged 7 days were randomly divided into 3 groups,with 16 rats in each group.Group S1 and group S2 inhaled 3% sevoflurane for 2 and 6 hours respectively.Group C received no treatment.The effects of spatial learning and memory function were assessed with Morris water-maze test by day 16 to 20 after rats were born.On the second day after inhalation and Morris water-maze test,hippocampus were removed to determine AchE and ChAT activity with colorimetry.Results The escape latency prolonged in group S1 and group S2 from the second training day to the fifth training day compared with group C（P0.05）,and prolonged in group S2 from the fourth training day to the fifth training day compared with group S1（P0.01）.The result of colorimetry showed after sevoflurane inhalation,the AchE and ChAT activity expression was up-regulated in group S1 and group S2 compared with group C（P0.01）.And Morris water-maze test showed the AchE activity was up-regulated both in group S1 and group S2 compared with group C（P0.05）,but there was no significant difference in ChAT activity between two groups（P0.05）.Conclusion 3% Sevoflurane inhalation anesthesia in infant rats can decrease the spatial learning and memory function by increasing AchE activity and decreasing ChAT activity in hippocampal.The effect is more obvious in inhalation for 6 hours than that for 2 hours.