BMP7蛋白对大鼠急性脊髓损伤后神经元修复作用的研究*

目的探索骨形态发生蛋白7(bone morphogenetic protein 7, BMP7)是否具有促进大鼠急性脊髓损伤后神经元修复的作用。方法实验大鼠分为阴性对照组（negative control，NC）和BMP7实验组，以Allen′s打击法建立大鼠脊髓损伤模型，BMP7组大鼠每天在脊髓损伤处注射50ng BMP7蛋白，连续7d，NC组对应注射等体积的0.9%氯化钠注射液。两组大鼠分别于术后6小时、3 天、1周、2周、4周、8周进行HE染色以观察脊髓损伤处病理学改变；两组大鼠分别于术后6小时、3天、1周、2周、4周、8周进行免疫组化实验以检测损伤节段脊髓神经丝蛋白200( neurofilament protein 200, NF200)、胶质纤微酸性蛋白（glial fibrillary acidic protein，GFAP）及突触素(Synaptophysin，SYP)蛋白表达水平。结果 HE染色结果表明两组大鼠造模后脊髓损伤处神经元数量减少，神经突触数量减少，尼式体淡染且数量减少，组织中可见空洞形成，1周后，BMP7实验组大鼠脊髓损伤处尼式体染色逐渐加深，神经突触数量增多，变化较NC组明显。免疫组化结果表明BMP7实验组大鼠NF200阳性表达细胞数造模3天后逐渐增多，至第4周时达到高峰，且在1周、2周、4周及8周时均大于NC组；BMP7实验组及NC组术后GFAP阳性表达细胞数变化均不明显，且两组阳性细胞数差异不显著；BMP7实验组大鼠SYP阳性表达细胞数造模3天后逐渐增多，且在1周、2周、4周及8周时均大于NC组。结论 BMP7蛋白可以促进大鼠脊髓损伤后神经元的修复。

英文摘要:

Objective To explore whether the BMP7 protein has the effect of promoting neuronal repair after acute spinal cord injury in rats. Methods The experimental rats were divided into negative control group and BMP7 group; we used the Allen's strike method to establish a rat spinal cord injury model. BMP7 rats were injected with 50ng BMP7 protein in the spinal cord injury for 7 days; the negative control group was injected with 0.9% sodium chloride injection. HE staining was performed at 6h, 3d, 1 week, 2 week, 4 week and 8 week after operation to observe the pathological changes of spinal cord injury. The expression of NF200, GFAP and SYP protein in injured spinal cord were detected by immunohistochemistry at 6h, 3d, 1 week, 2 week, 4 week and 8 week after operation. Results The results of HE staining showed that the number of neurons in the spinal cord injury decreased, the number of neuron synapses decreased, the number of Nissl bodies decreased, and the voids were found in the tissues. After 1 week, the staining of Nissl bodies in spinal cord injury in BMP7 group increased gradually, and the number of synapses increased, which was significantly higher than that of negative control group. The results of immunohistochemistry showed that the number of NF200-positive cells in BMP7 group increased gradually after 3 days, reached the peak at the 4th week, and was more than NC group at 1 week, 2 week, 4 week and 8 week. The number of GFAP-positive cells in BMP7 group and negative control group was not significantly changed, and the number of positive cells in the two groups was not significant. The number of SYP-positive cells in BMP7 group increased gradually after 3 days, and was more than NC group at 1 week, 2 week, 4 week and 8 week. Conclusion BMP7 protein can promote the repair of neuron and axons after spinal cord injury in rats.

查看全文查看/发表评论下载PDF阅读器