一氧化氮对足炎性刺激大鼠背角c-fos表达的影响

Effects of NO on c-fos expression in the bilateral spinal dorsal horn of rats with one hindpaw inflamed

目的 应用一氧化氮合酶 (NOS)抑制剂氮ω 硝基 左旋精氨酸甲基乙酯 (L NAME)和一氧化氮 (NO)供体观察NO对单足致炎大鼠脊髓背角两侧c fos表达的影响。方法 雌性Wistar大鼠 30只 ,体重 2 5 0～ 2 80 g ,随机分为五组 :正常组、盐水对照组、致炎组、L NAME组和SNP组。盐水组、致炎组于一足底中心略凹处皮下分别注入生理盐水和 1%角叉菜胶 0 1ml。L NAME组、SNP组分别预先腹腔注射L NAME 10 0mg/kg和SNP 2mg/kg ,30min后足底 1%角叉菜胶 0 1ml致炎。所有大鼠足底注药 2h后灌杀取L5脊髓 ,冰冻切片行Fos免疫组化染色。结果 脊髓背角FLI神经元计数 :(1)致炎侧 ,各实验组均较正常组显著增加 (P <0 0 5 ) ,L NAME组较单纯致炎组显著减少 (P <0 0 5 )。 (2 )非致炎侧 ,盐水组较正常组、致炎组和L NAME组显著增加 (P <0 0 5 )。 (3)致炎组、L NAME组和SNP组的致炎侧明显高于非致炎侧 (P <0 0 5 )。结论 致炎局部产生痛觉过敏 ,远隔部位产生“抗痛反应”。NO在致炎局部痛敏形成中起一定作用 。

Objective Using NOS inhibitor and NO dornor to observe the effects of NO on c fos expression in bilateral spinal dorsal horn of rats with one hindpaw inflamed Methods Adult female Wistar rats( n= 30, 250 280g) were divided into five groups: normal group;saline group;inflamed group; L NAME group and SNP group In the saline and inflamed groups, rats were injected subcutaneously with saline or carragenin in one hindpaw respectively In the L NAME and SNP groups, rats were injected intraperitoneally with L NAME 100mg/kg or SNP 2mg/kg respectively 30 min before one hindpaw was inflamed by carragenin Two hours later, all rats were killed and then L 5 spinal segments were removed for section and localization of FOS immunoreactivity Results In the ipsilateral dorsal horn of inflammation,the number of FLI neurons of the latter four groups was more than that of normal group( P< 0 05) The number of FLI neurons of L NAME group was significantly less than that of inflamed group( P< 0 05);In the contralateral dorsal horn of inflammation,the number of FLI neurons of saline group was more than that of normal,L NAME or inflamed group( P< 0 05) The number of FLI neurons In inflamed, L NAME and SNP groups was markedly higher on the ipsilateral side than that on the contralateral( P< 0 05) Conclusion Hyperalgesia exist in the local area of the inflammation,and an anti pain response may be seen in the remote area NO plays a certain role in producing hyperalgesia in local inflammation area But the mechanism for the antinociceptive reaction in the remote area of inflammation needs to be studied further