米诺环素抑制面部福尔马林炎性疼痛大鼠三叉神经脊束核尾侧亚核c-fos的表达

目的：观察腹腔预先注射米诺环素（minocycline）对面部福尔马林炎性痛大鼠三叉神经尾侧亚核（Vc）c-fos表达的影响。方法：60只雄性大鼠随机分为正常对照组（n=10）、假操作对照组（n=10）和福尔马林实验组（n=40）。福尔马林实验组大鼠在其左上唇皮下注射2．5％福尔马林50斗l建立炎性痛模型，在注射福尔马林前1h预先腹腔注射容量均为15ml的米诺环素（45mg／kg）或生理盐水，以预先注射药物和成活时间不同（1或2h）分为4个亚组（每个亚组10只）。免疫组织化学染色和免疫印迹法蛋白定量分析各组大鼠同侧Vc核c-fos表达的情况。结果：在面部皮下注射福尔马林后，大鼠Vc核内迅速出现C--fos表达增加，而且c-fos的表达在短时间内显著增强。与注射生理盐水组相比，预先腹腔注射米诺环素组c-fos的表达明显减少。结论：预先腹腔注射米诺环素可有效抑制福尔马林炎性痛诱发三叉神经脊束核尾侧亚核内c-fos的表达。

Systemic administration of minocycine inhibits formalin-evoked c-fos expression in VC of rats

Objective： To observe the effects ofintraperitonial（i.p.） preadministration ofminocycline on the formalin-evoked c-fos expression in ipsilateral trigeminal nucleus candal（Vc） of rats. Methods： 60 SD rats were divided into four experimental groups,one control group and one sham-operated group （n=10）.The experimental rats received subcutaneous injection of 2.5% formalin 50μl in the left vibrissa pad to establish the inflammatory pain model. 1 hour before formalin injection,minocycline 45mg/kg or 0.9% normal saline,all in volume of 15ml,were intraperitonially injected.The survival time of animals were 1 and 2 hours after operation with 10 rats for each manipulation at each time point.In addition,10 rats received subcutaneous injection of normal saline as sham-operated,10 normal rats without operation as control.The c-fos expression in ipsilateral Vc was detected by immunohistochemistry and Western Blot. Results： There appeared a rapid and persistent enhancement of c-fos expression in the ipsilateral Vc after subcutaneous injection of formalin. Furthermore, with the time passing by, the increase in the number of fos-like immunoreactivity （ FLI ）neurons seemed more obvious.As compared to NS group,the expression of c-fos was decreased obviously in minocycline groups. Conclusion： Intraperitonial preadministration of minocycine can effectively inhibit formalin-evoked c-fos expression in ipsilateral trigeminal nucleus candal of rat.