摘要目的 通过制备幼鼠罗哌卡因毒性惊厥模型,观察其对幼鼠成年后学习记忆能力和突触后致密物蛋白-95( post synaptic density-95protein,PSD-95)表达的影响.方法 选用18日龄Sprague -Dawley (SD)幼鼠20只,采用随机数字表法分为罗哌卡因组(R组)和生理盐水组(N组)2组,每组10只.连续水迷宫训练3d,每天2次,达到标准者纳入实验(潜伏期≤120 s).于21日龄分别经腹腔单次注射罗哌卡因(33.8 mg/kg)和生理盐水(0.1 ml/kg).出现惊厥鼠纳入实验,常规饲养至第55日龄再次行水迷宫测试.前3d为训练学习阶段,每天训练两次.第4天测试记忆能力.测试结束后选取5只取海马组织,采用Weston Blot技术行PSD-95含量测定.另两组各取5只,取右侧海马CA1区于电镜下观察突触后致密物厚度(post synaptic density,PSD)变化.结果 R组和N组水迷宫测试第1天潜伏期分别为(12.6±3.4)、(10.5±4.1)s；第2天潜伏期分别为(6.8±2.8)、(7.1±1.3)s；第3天潜伏期分别为(6.2±0.7)、(6.4±1.1)s；第4天潜伏期分别为(5.0±2.7)、(8.1±4.0)s；训练阶段和第60日龄潜伏期之间差异均无统计学意义(P＞0.05).R组和N组PSD-95蛋白含量基础值和60日龄分别为(0.60±0.08)、(0.61±0.05),两组差异无统计学意义(P＞0.05).R组和N组60日龄PSD厚度分别为(84±6)、(81±7) nm,两组差异无统计学意义(P＞0.05).结论 幼年期单次罗哌卡因毒性惊厥对成年后鼠学习记忆、PSD-95蛋白及PSD厚度无明显影响.

abstractsObjective To investigate the effect of juvenile convulsion induced by ropivacaine toxicity on adult learing,memory and post synaptic density-95protein(PSD-95) protein expression in rats. Methods Twenty Sprague-Dawley(SD)rats(age=18 d) were randomly divided into ropivacaine group(R group) and saline group(N group)(n=10).Morris water maze was performed on rats in the both groups for 3 days,2 times per day,rats fulfilling the standards were included in the experiments (latency period ≤ 120 s).Rats in the R group were intraperitoneally injected with 33.8 mg/kg ropivacaine,and those in the N group were injected with 0.1 ml/kg saline when rats were 21days old.The rats convulsed were adopted and performed with morris water maze again as before when they were 55 days old,4 days later memory test was performed.The sections of hippocampus were collected at the end of test,PSD-95 expression and post synaptic density(PSD) thickness was detected by Weston Blot and electron microscope,respectively(n=5). Results There was no significant differences in latency between the R group and the N group[d1(12.6±3.4) vs (10.5±4.1) s,d2 (6.8±2.8) vs (7.1±1.3) s,d3 (6.2±0.7) vs (6.4±1.1) s,d4 (5.0±2.7) vs (8.1±4.0) s respectively(P＞0.05)].There was no significant differences in PSD-95(0.6±0.1 ) vs (0.6±0.0) respectively(P＞0.05)and PSD(84±6),(81±7) nm,respectively(P＞0.05)between the R group and the N group. Conclusions There was no significant effect of juvenile convulsion induced by ropivacaine toxicity on adult learing,memory,and PSD-95 in rats.