nNOS 基因在大鼠实验性脑震荡中的表达研究

目的 :探讨nNOS在大鼠实验性脑震荡中的表达及意义。方法 :采用Wistar雄性二级大鼠复制脑震荡动物模型 ,于伤后 1,3,7,14及 30d活杀取脑组织 ,经免疫组化和原位杂交等技术 ,研究nNOS在脑震荡中的变化规律。结果 :10 0g(致脑震荡砝码 )组见典型脑震荡的临床表现 ,其病理改变为脑血管扩张 ,脑组织淤血、水肿 ,神经元变性、坏死 ,尼氏体减少甚至消失。nNOS蛋白和mRNA于伤后 3d表达增强 ,7d达高峰 ,14d后开始减少 ,30d仍呈阳性表达。阳性部位见于大脑皮层、海马、丘脑和小脑神经元胞浆内。结论 :脑震荡以血液循环障碍和实质细胞变性、坏死为主要病理改变 ;nNOS基因表达参与脑震荡发生时脑组织损伤的病理过程 ,可能对神经细胞变性、坏死起重要调节作用。

Expression of neuron nitric oxide synthase (nNOS) gene in rat cerebral concussion

Objective:To study the expression of nNOS gene in rat cerebral concussion. Methods:Eighty male Wistar rats were used for animal model of cerebral concussion.They were sacrificed on 1,3,7,14 and 30 days after injury and the brain tissue was taken. The expression of nNOS gene was studied in the course of cerebral concussion by means of immunohistochemistry and in situ hybridization.Results:Clinical manifesfation of typical cerebral concussion was seen in rats of 100?g(the weight causing concussion) group. The pathologic changes were the cerebral vascular dilatation, congestion,edema of cerebral tissue,neuronal degeneration, necrosis,obvious decrease and even disappearance of the Nissl bodies. The protein and mRNA of nNOS were increased on day 3,peaked on day 7, decreased on day 14 and were still positive on day 30. The positive area was seen in the cytoplasm of neurons in cerebral cortex,hippocampus, thalamus and cerebellum. Conclusions:The main pathologic changes of cerebral concussion were blood circulatory disorder and nervous cell degeneration and necrosis. The expression of nNOS gene participated in the course of cerebral concussion and may play an important role in the nervous cell degeneration and necrosis.