重组腺相关病毒神经肽Y基因转染对癫大鼠海马病理变化的影响

Effect of recombinant adeno-associated virus-mediated human-derived neuropeptide Y gene transfection on pathological change of the hippocampus in epileptic rat

目的观察重组腺相关病毒介导人源性神经肽Y(rAAV-hNPY-EGFP)基因转染对癫大鼠海马病理变化的影响。方法 28只Wistar大鼠随机分为点燃组(n=20)和正常对照组(n=8)。正常对照组不进行特殊处理,点燃组以大鼠海马内多次注射红藻氨酸(KA)建立慢性癫模型,造模成功16只,其随机分为模型组和神经肽Y(NPY)治疗组,每组各8只大鼠。NPY治疗组大鼠转染rAAV2/1-hNPY-EGFP基因,模型组未转染。转染4周后,每组取6只大鼠海马行苏木精-伊红染色,2只行电镜观察。结果苏木精-伊红染色显示:正常对照组大鼠海马CA3区神经元形态正常;模型组海马CA3区神经元丢失,胶质细胞增生;NPY治疗组基因转染后神经元丢失减少。模型组神经元数目为(10.67±7.87)个/视野,正常对照组为(81.42±5.63)个/视野,明显多于模型组(P<0.05);而NPY治疗组神经元数目为(65.73±2.81)个/视野,明显多于模型组(P<0.05)。电镜显示:正常对照组神经元结构正常;模型组神经元固缩,线粒体肿胀;NPY治疗组神经元线粒体结构完整。结论 rAAV-hNPY-EGFP基因转染可减轻大鼠癫发作引起的病理改变,发挥抑制癫的作用。

Objective To investigate the effect of recombinant adeno-associated virus-mediated human-derived neuropeptide Y gene（rAAV-hNPY-EGFP gene） transfection on pathological change of hippocampus in epileptic rat.Methods A total of 28 Wistar rats were randomly divided into kindling group（n=20） and normal control group（n=8）.No special treatment was performed on rats in normal control group.The chronic epileptic models were successfully established in 16 rats by repeated injection of kainic acid into the hippocampi of rats in kindling group which were equally subdivided into two groups： model group and neuropeptide Y（NPY） treatment group.The rats were transfected with rAAV2/1-hNPY-EGFP gene in NPY treatment group and no transfection was made in model group.The hippocampi of rats were sampled 4 weeks after transfection,and the samples were examined by hematoxylin-eosin staining in 6 rats and by transmission electron microscopy in 2 rats in each group.Results Hematoxylin-eosin staining results showed normal neuronal form in CA3 area of the hippocampus in normal control group,neuron loss and gliosis in CA3 area in model group,while the loss of neurons decreased in NPY treatment group.The number of neurons was 10.67±7.87 cells per visual field in model group and 81.42±5.63 cells per visual field in normal control group.There was a significant difference in the number of neurons between the above two groups（P 0.05）.The number of neurons was 65.73±2.81 cells per visual field in NPY treatment group,which was obvious more than that in model group（P 0.05）.Electron microscopy results showed normal neuronal form in normal control group,and neuronal pyknosis and mitochondrial swelling in model group,while the mitochondrial structures kept intact in NPY treatment group.Conclusions rAAV-hNPY-EGFP gene transfection can relieve the pathological change induced by seizures and exert an antiepileptic effect in epileptic rats.