中文摘要：

目的：研究坐骨神经结扎损伤后诱导型一氧化氮合酶（iNOS）在大鼠脊髓内的表达变化规律。方法：健康成年SD大鼠随机分为正常组、假手术组和坐骨神经结扎组,存活1、3、5、7、14、21、28 d后取腰4～6脊髓节段冷冻切片,用免疫组织化学方法结合图像分析技术检测脊髓内i NOS的表达变化,同时用免疫荧光双标染色技术检测14 d组中央管周围iNOS和神经肽Y（NPY）的共表达。结果：根据免疫阳性产物灰度值,损伤侧脊髓前角iNOS表达1 d明显升高,21 d达高峰,28 d接近正常,损伤后1～21 d损伤侧脊髓前角与对侧和正常组免疫阳性产物相比有统计学意义;损伤侧脊髓后角1 d iNOS表达增强,其他各组未见明显变化;损伤后中央管周围免疫阳性细胞数增多,3 d尤为明显,28 d恢复正常,免疫荧光双标染色显示14 d组i NOS和NPY在中央管周围共表达。结论：iNOS可能参与神经损伤后的再生过程及伤后神经性痛的调节。

英文摘要：

Objective： To investigate the changes of iNOS expression in rat spinal cord early after sciatic nerve crush injury. Methods： Adult SD rats were randomly divided into normal group, sham-operated group and right sciatic nerve crush group. Being survived for 1, 3, 5, 7, 14. 21 and 28 d after operation, the L4-6 spinal cord was isolated and sectioned iNOS immunohistochemical staining and iNOS and NPY double immunofluorescence staining were used in slices from 14 d group. Results： According to immuno-positive gray scale, there was low expression of iNOS in the L4-6 spinal cord of normal and sham-oper ated animals, and there was no significant differences between these two control groups. After sciatic nerve ligation, iNOS expression in the ipsilateral spinal ventral horn began upregulation at day 1, and peaked at day 21, and returned almost to normal at day 28. But iNOS expression in the ipsilateral spinal dorsal horn was only significantly upregulated at day 1. After injury, the number of iNOS immuno-positive cells increased around the central canal, especially at day 3. Co localization of iNOS and NPY was found in central canal of spinal cord by immunofluorescence in 14 d group. Conclusion： The upregulation of iNOS in the spinal cord after sciatic nerve ligation suggests that it may participate in the process of peripheral nerve degeneration and regeneration, and may also play a role in modulation of traumatic neuropathic pain.