【摘要】 目的 :采用福尔马林疼痛动物模型 ,定量比较颌面部不同浓度福尔马林刺激后动物疼痛行为和中枢神经元c-fos表达。方法 :第Ⅰ～Ⅳ组分别于大鼠右侧上唇皮下注射 5 0 μl 5 %、2 .5 %、1.5 %福尔马林液和生理盐水 ;第Ⅴ组右侧眶下注射 1%Articaine 30 0 μl,10min后再于右侧上唇皮下注射 5 %福尔马林 5 0 μl。记录比较注射后 1h内动物疼痛行为 ,2h后的脑干切片c -fos表达阳性神经元数目。结果 :不同浓度福尔马林液刺激均可诱发典型的两个时相性的疼痛反应 ,5 %福尔马林诱发更明显的疼痛行为 ,但并没有产生更多的擦面行为。脑干三叉神经脊索核c-fos表达量与福尔马林浓度高度相关。结论 :擦面行为是颌面部福尔马林刺激引起的特异性疼痛行为 ,可反映伤害性刺激强度 ,但浓度宜低于 2 .5 % (或 2 .5 % )。中枢c-fos表达是外周伤害性刺激后神经元兴奋的标志 ,c-fos表达量可代表外周伤害性刺激强度更多还原

【Abstract】 Objective:The aim of the study is to detect whether c -f os expression in the brainstem or the face-rubbing behavior reflects the inten sity of noxious stimulus by subcutaneously formalin injected into the orofacial region.Methods:All twenty-five Sprague-Dawley rats were di vided into five groups.The group Ⅰ to group Ⅳ animals received respectively 5% , 2.5%, 1.5% formalin and saline 50μl subcutaneously injections into the right upper lip.The group Ⅴ were treated 300μl 1% Articaine 10 min before the same v olume of 5% formalin injection.The animal’s nocieptive behaviors were recorded within 1 hour, and c-fos immunohistochemistry in the brainstem was performed 2 hours following injection.Results:The orofacial formali n injection produces a characteristic two-phase face-rubbing behavior which was related to pain, but high concentration of formalin could not induce more face-r ubbing behavior.The quantitative c-fos expression in the subnucleus caudalis (Vc) was highly associated with the concentration of the injected formalin.Conclusions:The formalin test is a convenient method for the s tudy of orofacial pain, and the face-rubbing behavior is one objective, reproduc ible and quantifiable response related to pain intensity, but 2.5% formalin or l ower was recommended. c-fos expression is a useful marker for nociceptive neu rons, and the magnitude of expression should be related to stimulus intersity.更多还原