【摘要】 目的探讨并比较托吡酯(topiramate,TPM)和促红细胞生成素(erythropoietin,EPO)对癫痫大鼠神经元的保护作用及机制。方法建立致痫前即用TPM及EPO干预的新型癫痫大鼠模型。将86只成年雄性SD大鼠随机分为健康对照组、单纯致痫组(SE组)、TPM[按体重50 mg/(kg.d)]干预后致痫组(TPM50组)、TPM[按体重100 mg/(kg.d)]干预后致痫组(TPM100组)、重组人促红细胞生成素(r HuEPO)[按体重5000 U/kg]干预后致痫组(EPO组)。采用Morris水迷宫和悬吊实验方法检测致痫前后大鼠学习记忆功能及悬吊耐受性变化,采用免疫组化法检测神经元caspase-3活性变化,应用流式细胞仪和电镜检测神经元凋亡情况。结果(1)TPM50组及TPM100组致痫前寻找平台潜伏期与对照组比较差异均有统计学意义(P<0.05),致痫后TPM50组与对照组差异具统计学意义(P<0.05);致痫前后EPO组寻找平台潜伏期与对照组比较差异无统计学意义(P>0.05)。致痫前TPM50组和TPM100组悬吊耐受时间均短于对照组(P<0.05),而致痫后两组均有逆转,与对照组比较差异无统计学意义(P>0.05);致痫前后EPO组悬吊耐受时间与对照组比较差异无统计学意义(P>0.05)。(2)SE组及TPM50组电镜下可见凋亡神经元,而其他组则无此所见。(3)对照组、SE组、TPM50组、TPM100组和EPO组神经元凋亡率分别为0.4%、9.9%、7.8%、0.7%和0.5%。TPM100组及EPO组与对照组比较差异无统计学意义(P>0.05),与SE组比较差异有统计学意义(P<0.05);TPM50组与SE组差别无统计学意义(P>0.05)。(4)SE组和TPM50组其额皮质活化型caspase-3的表达较健康对照组多(P<0.05);活化型caspase-3的表达与神经元凋亡率呈正相关(r=0.955,rs=1.000)。结论(1)大剂量TPM及EPO均可保护癫痫持续状态后大鼠海马及额叶皮质神经元免受损伤。(2)大剂量TPM及EPO的神经元保护作用可能通过抑制caspase-3活化实现。(3)TPM可影响癫痫大鼠的功能行为,而EPO则无此作用。更多还原

【Abstract】 Objective To investigate and compare neuroprotective effects and the possible mechanism of topiramate(TPM) and erythropoietin(EPO) in this model.Methods A new model of epilepsy was developed in rats after intervention of TPM and EPO.86 adult male Sprague-Dawley rats were randomized to five groups: normal control group(N group),status epilepticus group(SE group),the intervention group with topiramate 50 mg/(kg·d)(TPM50 group),the intervention group with TPM 100 mg/(kg·d)(TPM 100 group)and the intervention group with rHuEPO 5000 U/kg(EPO group).Rats were evaluated for visual-spatial memory in water maze,suspend tolerance in suspension test before and after SE.Then they were evaluated with immunohistochemistry to determine caspase-3 expression and activation in neurons.Cell apoptosis was examined by the flow cytometer and transmission electron microscope.Results (1) In water maze test for visual-spatial memory,the TPM50 group and TPM 100 group had significant deviation of the time in looking for flat roof with the normal control group before SE(P<0.05).And the TPM50 group remained significant deviation with the normal control group even after SE(P<0.05).The time of suspend tolerance in the TPM50 group and TPM 100 group had significant deviation with the normal control group before SE(P<0.05).The EPO group had no difference with the normal control group in water maze test and suspend test,no matter before or after SE(P>0.05).(2) Apoptosis cells were observed in the SE group and TPM50 group with the transmission electron microscope, but no apoptosis had been found in other groups.(3) In the result of the flow cytometer,the N group was 0.4%,SE group was 9.9%,TPM50 group was 7.8%,TPM 100 group was 0.7% and EPO group was 0.5% respectively.The TPM 100 group and EPO group had no difference with the normal control group(P>0.05),but had significant deviation with SE group(P<0.05).The TPM50 group had no difference with the SE group(P>0.05).(4) The activated form of caspase-3 was most pronounced in the SE group and TPM50 group.The activated form of caspase-3 in the hippocampal and prefrontal cortex of the two groups were significantly improved compared with the N group(P<0.05).In addition,the amount of activated caspase-3 expression had a high positive correlation with apoptosis rate(r=0.955,rs=1.000).Conclusions (1) TPM and EPO displayed neuroprotective properties in the hippocampal and frontal cortex of the rats following status epilepticus.(2) The neuroprotective action of TPM and EPO seems to be related to their inhibitory effect on activated caspase-3 expression.(3) TPM might impair the neurol behavior of rats,but EPO would not.更多还原