大鼠脊髓压迫损伤后COX-2基因和蛋白的表达

目的观察大鼠脊髓压迫损伤后COX-2mRNA和蛋白在脊髓组织内表达的时间特征,以及COX-2的空间分布特点。方法以压迫装置致脊髓损伤后,在伤后不同时间点(30min、3h、6h、24h、72h、1w)分别应用RT-PCR、Western blotting、免疫组化技术检测COX-2mRNA和蛋白表达和分布。结果RT-PCR和Western blotting显示,COX-2mRNA和蛋白伤后30min表达开始增加,于伤后6h达到峰值,伤后1w表达接近基础水平。免疫组化提示,COX-2蛋白在假手术组表达仅见于脊髓血管内皮细胞,伤后COX-2蛋白表达见于损伤区附近脊髓灰质内的神经元和血管内皮细胞,损伤中心部位COX-2免疫阳性细胞少见。结论脊髓压迫损伤早期可快速诱导COX-2基因的表达上调和蛋白的合成,伤后COX-2蛋白分布发生变化,主要位于脊髓神经元和血管内皮细胞。

Expression of Cyclooxygenase-2 Gene and Protein in Rat Injuried Spinal Cord

Objective To study the temporal and spatial expression patterns of the COX-2 gene and protein levels in the spinal cord after compression injury.Methods lschemic injury of spinal cord in rats was induced with Nystrom s compression method.The expression and distribution of COX-2mRNA and protein in adult Wistar rat spinal cord were studied by RT-PCR and Western blotting and immunohistochemical method at different injuried times(30min,3h,6h, 24h,72h,1w).Results RT-PCR and Western blotting showed that expression of COX-2 gene and protein in the spinal cord increased within 30 min,peaked at 6h,approached basal level 1 week after injury of the spinal cord. Immunohistochemicai staining result revealed that COX-2 immunoreactivity was present only in endothelial cells of blood vessels in sham operated rat spinal cord,but also found in neurons and endothelial cells of blood vessels around lesion area with less immunoreactive positive cells in the lesion core in injuried spinal cord.Conclusion Upregulation of COX-2 gene and protein synthesis occured quickly at early phase after spinal cord compression injury,with more expression in neurons and endothelial cells of blood vessels after spinal cord injury.