【摘要】 目的研究不同麻醉药物对发育期大鼠学习记忆的影响。方法将30只新生大鼠随机分为3组,于出生后6、8、10d分别给予氯胺酮(单药麻醉组)、氯胺酮复合丙泊酚(复合麻醉组)或0.9%氯化钠溶液(对照组)处理。于出生后41d对大鼠进行旷场实验,记录其运动总路程、中央区停留时间和运动速度。于出生后45d对大鼠进行Morris水迷宫训练,训练第1~4天行定向航行实验,记录其逃避潜伏期、寻找平台的总路程和寻找平台的速度;训练第5天行空间探索实验,记录其原平台所在象限的停留时间、穿越平台的次数和原平台位置的停留时间。于出生后60d对大鼠进行条件恐惧训练,记录大鼠训练期、场景恐惧测试、声音恐惧测试的凝滞率。结果 3组间运动总路程、中央区停留时间、运动速度的差异均无统计学意义(P值均>0.05)。定向航行实验结果显示,3组训练第2、3、4天寻找平台的总路程均较同组训练第1天显著缩短(P值均<0.05),单药麻醉组和对照组训练第2、3、4天的逃避潜伏期均较同组训练第1天显著缩短(P值均<0.05),3组训练第3、4天寻找平台的总路程和逃避潜伏期均较同组训练第2天显著缩短(P值均<0.05);3组训练第4天寻找平台的总路程和逃避潜伏期均较同组训练第3天显著缩短(P值均<0.05),3组内训练第1、2、3、4天间寻找平台的速度的差异均无统计学意义(P值均>0.05)。复合麻醉组训练第2天的逃避潜伏期显著长于单药麻醉组和对照组同时间(P值均<0.05),3组间训练第1、2、3、4天寻找平台的总路程和寻找平台的速度的差异均无统计学意义(P值均>0.05)。空间探索实验结果显示,3组间原平台所在象限的停留时间、穿越平台的次数、原平台位置的停留时间的差异均无统计学意义(P值均>0.05)。3组场景恐惧测试和声音恐惧测试的凝滞率均显著高于同组训练期(P值均<0.05)。结论在脑发育的关键期,氯胺酮与丙泊酚复合麻醉较单用氯胺酮麻醉可能更易导致发育期大鼠空间学习记忆发生减退,但对大鼠恐惧记忆无影响。更多还原

【Abstract】 Objective To explore whether different administration of anesthetic agents(alone or in combination)to neonate rats can trigger learning and memory deficit in adulthood.Methods Thirty neonate rats were randomly divided into 3groups and administrated with ketamine(ketamine group),ketamine plus propofol(combination group),or normal saline(control group)on day 6,8and 10 postnatally.On day 41 after birth,open field test was performed to record total distance,central duration and average velocity of rats.On day 45 after birth,learning and memory ability was assessed by Morris water maze.Navigation test was conducted for 4d,and the latency to platform,total distance and average velocity were recorded from day 1to day 4.On day 5of training,space exploratory test was performed and the duration that rats spent in previous quadrant and former platform and frequencies that rats passed through former platform were recorded.On day 60 after birth,rats underwent fear conditioning test,and then freezing rate of training,contextual test and tone test were recorded.Results There were no significant differences in the total distance,central duration or average velocity during open field test between groups(all P>0.05).Navigation test showed that the total distance to platform on day 2,3and 4of training was significantly shorter than that on day 1in all rats(all P<0.05).The latency to the platform on day 2,3and 4of training was significantly shorter than that on day 1in ketamine group and control group(all P<0.05).The total distance and latency to platform on day 3and 4of training was significantly shorter than that on day 2in all rats(all P<0.05).The total distance and latency to platform on day 4of training were significantly shorter than those on day 3in all rats(all P<0.05).There was no significant difference in the average velocity in all rats between the first four training days(all P >0.05).The latency to platform on day 2of training in combination group was significantly longer than that in ketamine group and control group(both P<0.05).There were no significant differences in the total distance or average velocity between groups on day 1to day 4of training(all P>0.05).There were no significant differences in the duration that rats spent in previous quadrant and former platform or frequencies that rats passed through former platform between groups(all P>0.05).The freezing rates of contextual test and tone test were significantly higher than those of training period in each group(all P<0.05).Conclusion Ketamine combined with propofol may increase the risk of spatial learning disability as compared with ketamine alone,but either ketamine or propofol will not affect fear memory during the critical period of brain growth.更多还原