局部辣椒素处理抑制福尔马林诱导的脊髓fos表达(英文)

辣椒素是一种阻断伤害性传入(C-纤维)的工具药,利用免疫组织化学技术,本工作发现1％辣椒素包埋坐骨神经可抑制福尔马林(5％,150μl,后肢脚掌注射)诱导的脊髓背角Ⅰ—Ⅱ,Ⅲ—Ⅳ,Ⅴ—Ⅵ层fos蛋白表达(P<0.01),本结果提示C-纤维的激活参与c-fos基因的诱导,同时也说明外周辣椒素处理是阻断伤害性初级传入的有效途径。

Topical capsaicin treatment suppresses formalin-induced fos expression in rat spinal cord

Capsaicin (Cap) is a pharmacological tool to inactivate nociceptive afferents. The present study was undertaken to investigate the effects of topical application of Cap to sciatic nerve on the formalin-induced expression of proto-oncogene proteins c-fos in the rat spinal cord using immunohistochemical display of fos-like protein. In rats subjected to formalin injection into the hind paw, numerous fos-like immunoreac-tivity (FLI) neurons were found in the spinal dorsal horn, with heavy labeling in laminae I - II and V - VI. Following pretreatment of Cap, formalin-induced FLI expression was significantly abolished. It was suggested that activation of Cap-sensitive unmyelinated nociceptive afferents following formalin injection was primarily responsible for the activation of c-fos gene. Our data also provided further evidence supporting that topical application was an effective way to block the transmission of noxious primary afferents.