脑外伤后大鼠脊髓内去甲肾上腺素能神经元变化的研究  

Changes in noradrenergic neurons in the rat spinal cord after brain injury

作　　者：余维华[1] 孙善全[1] 汪克建[1] 贺桂琼[1] 杨美[1] 

机构地区：[1]重庆医科大学解剖学教研室,重庆 400016

出　　处：《中国危重病急救医学》2007年第6期349-352,I0001,共5页Chinese Critical Care Medicine

基　　金：国家自然科学基金项目（30270437）,教育部春晖计划基金资助

摘　　要：目的观察脑外伤应激对大鼠脊髓内去甲肾上腺素（NA）能神经元的表达变化。方法成年Wistar大鼠70只,随机分为正常对照组（n=10）和闭合性脑外伤组（n=60）。采用Feeney′s法制备大鼠闭合性脑外伤模型。于伤后3、6、12、24、48和72h取出大鼠颈、胸、腰脊髓组织,分别用免疫组化和半定量逆转录-聚合酶链反应（RT-PCR）方法检测多巴胺-β-羟化酶（DBH）的表达变化。结果免疫组化显示,正常脊髓颈、腰膨大前角内可见少量DBH阳性神经元胞体;脑外伤后各时间点大鼠脊髓各个节段的前角、后角和胸腰段侧角均出现大量深染的DBH阳性神经元,其数量和染色较正常对照组差异均有显著性（P〈0.05或P〈0.01）。RT-PCR检测结果显示,脑外伤后各时间点脊髓内DBH mRNA表达明显强于正常对照组（P〈0.05或P〈0.01）。结论大鼠脑外伤后脊髓NA能神经元明显增多,NA能神经元DBH mRNA表达增加,说明NA合成增多,提示NA在脑外伤应激过程中起重要作用。Objective To investigate the impact of experimental brain injury on the noradrenergic （NA） neurons in the spinal cord, in order to explore possible mechanism of the changes in NA neuron expression. Methods Seventy healthy Wistar rats were randomly divided into two groups： normal group （n=10）, brain injury （BI） group （n=60）. The animals in BI group were subjected to BI with the modified Feeney＇s method. The spinal cords of rats were harvested at 3, 6, 12, 24, 48 and 72 hours after the injury, respectively. Immunohistochemistry （ IHC ） and reverse transcriptase - polymerase chain reaction （RT -PCR） were used to assess the changes in dopamine -β- hydroxylase （DBH） expression. Results IHC showed a small number of DBH -positive neurons distributed in anterior horn of the cervical and lumbar enlargements in control group; a larger number of dark - stained noradrenergic neurons were found in anterior horn, and also in posterior and lateral horns of spinal cord in brain injury group at different time points after injury, as compared with control group （P〈0.05 or P〈0.01）. RT- PCR showed that the expression of DBH mRNA in brain injury group was significantly higher than that in control group at different time points after injury （P〈0.05 or P〈0.01）. Conclusion A significant increase of NA neurons in spinal cord of brain injury group suggests that more NA is synthesized by the neurons, which is necessary to meet the demand of the organism under the stress condition, suggesting that NA plays a very important role in the course of brain injury.

关 键 词：脑损伤 创伤性 去甲肾上腺素能神经元 免疫组化 逆转录-聚合酶链反应 

分 类 号：R686[医药卫生—骨科学]