Abstract: Objective To explore the effects of sevoflurane on learning-memory and the signaling pathway of phosphatidylinositol -3- excitation enzyme (PI3K) / protein kinase B / (AKT) in juvenile rats,in order to provide theoretical evidence for related research . Method Totally 36 juvenile male SD rats (8 weeks old,220~250 g) were randomly divided into control group and experimental group using random number table.And the control group was divided into two subgroups:the vacuity contrast group (CON group) where rats were not treated and the positive control group (O₂ group) where rats inhaled pure oxygen for 30 minutes.The rats in the experimental group inhaled 2% sevoflurane for 30 minutes,and were divided into 4 subgroups:revive 2 h after anesthesia (T1 group),12 h (T2 group),24 h group (T3 group) and 72 h group (T4 group),with 6 rats in each group.All rats were trained by Morris water maze before anaesthesia.After anaesthesia,the Morris water maze behavior test was carried out again at every time point.The expression of PI3K mRNA and AKT mRNA in hippocampus of rats were detected by PCR method. Results There was no statistical difference in the behavior of rats in each group before anesthesia (P>0.05).Compared with the O₂ group,the escape latency after anesthesia was significantly prolonged in T1 group(P<0.05).Compared with the T1 group,the escape latency was shortened in T3 and T4 group(both P<0.05).There was no significant difference on the total route among each group (P>0.05).Compared with CON group,the expression of PI3K mRNA and AKT mRNA in O₂ group were significantly up-regulated,while the expression of PI3K mRNA and AKT mRNA in the T1 group were markedly down-regulated (all P<0.05).Compared with O₂ group,the expression of PI3K mRNA and AKT mRNA in T1 group significantly decreased (both P<0.05). Conclusions Sevoflurane anesthesia can cause temporary cognitive dysfunction in juvenile rats.And the mechanism is related to the inhibition of the expression of PI3K/AKT signaling pathway.

Key words: sevoflurane, learning-memory, signal pathway, PI3K/ AKT

摘要： 目的 探讨七氟醚对幼年大鼠学习记忆能力及磷脂酰肌醇-3-激酶(PI3K)/蛋白激酶B(AKT)信号通路的影响,为七氟醚对认知功能的影响及其机制提供理论依据。方法 幼年雄性SD大鼠36只,8周龄,体重220~250 g,采用随机数字表法,将大鼠随机分为对照组和实验组。其中对照组的分2个亚组,即完全空白对照组(CON组):大鼠不做任何处理;阳性对照组(O₂组):吸入纯氧30 min。实验组吸入2%七氟醚30 min,分为4个亚组即麻醉后苏醒2 h(T1组)、12 h(T2组)、24 h(T3组)、72 h(T4组),每组6只。麻醉前将各组大鼠进行Morris水迷宫训练。麻醉后于各时间点再次进行Morris水迷宫行为学测试。用PCR方法检测各组大鼠海马PI3K mRNA、AKT mRNA的表达变化。结果 麻醉前各组大鼠行为学检测比较差异无统计学意义(P>0.05)。麻醉后逃避潜伏期T1组明显延长,与O₂组比较差异有统计学意义(P<0.05);与T1组比较,T3、T4组逃避潜伏期缩短,差异有统计学意义(P<0.05);各组总路程比较差异无统计学意义(P>0.05)。与CON组比较,O₂组PI3K mRNA、AKT mRNA表达上调,差异有统计学意义(P<0.05),T1组PI3K mRNA、AKT mRNA表达下降,差异有统计学意义(P<0.05);与O₂组比较,T1组PI3K mRNA、AKT mRNA表达下降,差异有统计学意义(P<0.05)。结论 七氟醚麻醉可引起幼年大鼠发生一过性认知功能障碍,其机制与抑制PI3K/AKT信号通路的表达有关。

关键词: 七氟醚, 学习记忆, 信号通路, PI3K/AKT