脊髓横断损伤后局部灌注地塞米松对中枢神经系统胶质细胞增殖与神经细胞轴突的影响

Impact of local affused dexamethasone on the proliferation of glial cells and reaction of neuronal axons in spinal cord after transection

目的研究局部使用类固醇激素对损伤后中枢神经系统胶质细胞增殖和神经轴突变性坏死的影响。方法成年Wistar大鼠18只全部切断T10脊髓,6只横断间隙灌注地塞米松(DXM)为实验组,6只腹腔内注射DXM为全身用药组,另6只脊髓横断间隙灌注生理盐水为对照组。存活鼠5d后灌流固定取材石腊切片。选用神经中丝抗体(anti-neurofiblamentNF)和胶质纤维酸性蛋白抗体(anti-glialfibriallaryacidicproteinGFAP)对损伤脊髓的轴突和胶质细胞进行标记,用图象分析系统分析实验结果并进行分组统计学处理。结果实验组在损伤的脊髓残端GFAP阳性表达下调,而NF阳性表达上调,对照组结果相反,阳性面积均值实验组与对照组相比差异有显著性意义(P<0.01);实验组、腹腔注射组NF阳性表达均上调且二者出现差异有显著性意义(P<0.01);实验组、腹腔注射组GFAP表达差异有显著性意义,腹腔注射组与空白对照组GFAP表达结果比较差异也有显著性意义。结论脊髓损伤局部灌注与全身使用DXM相比可以有效地抑制胶质细胞增殖、保护神经细胞损伤后的变性坏死。

Objective To prove that dexamethasone in vivo c an inhibit the overgrowth of glial ce lls and preserve neronal axons of the injuried spinal cord.Methods Choose 18adult Wistar' s rat transect their spinal cords in T 10 ,6of them were affused by dexamethasone in local site of injury,6of them was inj ected with dexamethasone by subcuta neous(s.c.)while other 6rat as control by sodium chloride.5days later after surgery,all rats of spin al cord were taken.Use anti-NF and an ti-GFAP immunohis tochemistry to la bel the axons and glial cells in the injury site respectively.Analy se the results by the system of image p rocessing.Result Positive expresion of NF of the affused group and the s.c.group increased.positive o f GFAP was decreasing dramatically i n the affused group and the s.c.group.NF and GFAP of the affused group were significantly different from the control and the s.c.group.Conclusion Steroid hormones used in the injury o f spinal cord can not just decrease the reaction of lipid t o retain the structure and improve th e blood supply of spinal cord,but inhibit the proliferation of glial cell s.So that could regulate neuron repair ing course and preserve exist of spin al cord axons.