摘要
Objective:To explore the protective mechanisms of nerve growth factor (NGF) on spinal cord injury (SCI) and provide theoretical basis for its clinical application. Methods: The SCI of Wistar rats was done by Allens weight dropping way by a 10 g×2.5 cm impact on the posterior of spinal cord T 8. NGF (3 g/L, 20 μl) or normal saline was injected through catheter into subarachnoid space 2, 4, 8, 12 and 24 h after SCI. The expression of N-methyl-D-asparate receptor 1 (NMDAR 1) and neuronal constitutive nitric oxide synthase (ncNOS) mRNA in rat spinal cord was detected by in situ hybridization. Results: Abnormal expression of NMDAR 1 and ncNOS mRNA appeared in spinal ventral horn motorneuron in injured rats, as compared with that in control group. The expression of NMDAR 1 and ncNOS mRNA in NGF group was significantly lower than that in saline group (P<0.01). Conclusion: NGF can protect spinal cord against injury in vivo. One of the mechanisms is that NGF can prohibit NMDAR 1 and nitric oxide (NO) production after spinal cord injury.
目的 :探讨神经生长因子 (NGF)对脊髓损伤保护作用的机制 ,为其临床应用提供理论依据。方法 :采用Allen s法以 1 0g× 2 5cm力致伤大鼠T8脊髓 ,插蛛网膜下腔导管于术后 2h、4h、8h、1 2h、2 4h注入NGF溶液 (60 μg/ 2 0 μl)或生理盐水组。采用原位杂交法检测N 甲基 D 天门冬氨酸受体 1 (NMDAR1 )和神经元型一氧化氮合成酶 (nNOS)在脊髓中的表达。结果 :与正常组比较 ,大鼠伤后脊髓前角运动神经元出现NMDAR1和nNOSmRNA的异常表达 ,NGF组与生理盐水组相比较 ,NMDAR1和nNOSmRNA异常表达减少 (P <0 0 1 )。结论 :NGF能通过抑制脊髓损伤后NMDAR1和一氧化氮 (NO)的产生 ,从而保护了损伤的神经组织。
基金
agrantfromNationalNaturalScienceFoundationofChina (3980 0 176 )