皮内注射对急性内脏炎症痛大鼠的抗伤害效应和对脊髓Fos表达的影响

THE EFFECTS OF INTRACUTANEOUS INJECTION ON ACUTE VISCERAL INFLAMMATORY PAIN AND SPINAL FOS EXPRESSION INDUCED BY FORMALIN IN RATS

摘要:

目的:观察皮内注射对福尔马林诱导的急性内脏炎症痛大鼠是否具有抗伤害效应和对脊髓Fos蛋白表达的影响. 方法:实验选用SD大鼠随机分为7组:单纯福尔马林致炎组(F);0.25%利多卡因实验区皮内注射组(F-0.25%L-IN);0.25%利多卡因实验区外皮内注射组(F-0.25%L-OUT);0.125%利多卡因实验区皮内注射组(F-0.125%L-IN);0.125%利多卡因实验区外皮内注射组(F-0.125%L-OUT);生理盐水实验区皮内注射组(F-S-IN);生理盐水实验区外皮内注射组(F-S-OUT).对各组大鼠分别进行疼痛学评分,每15min为一个时间段,共4次,1h后取出S1脊髓节段以免疫组化法检测FLI阳性神经元. 结果:各组在第一个时间段内疼痛学评分差异无显著性(P＞0.05);在第三、第四个时间段内F组和F-0.25%L-IN、F-0.25%L-OUT、F-S-IN组相比疼痛学评分差异有显著性(P＜0.01)而和F-0.125%L-IN、F-0.125%L-OUT、F-S-OUT相比疼痛学评分差异无显著性(P＞0.05);脊髓Fos阳性神经元数量在F-0.25%L-IN、F-0.25%L-OUT、F-S-IN组均显著减少(P＜0.01). 结论:Fos阳性神经元可能参与了化学性致痛信息的传导和调控.

Abstract:

Objective:To determine whether intracutaneous injection has an antinociceptive effect on acute visceral inflammatory pain and spinal Fos expression induced by formalin in rats. Methods: The experimental SD rats were randomly divided into seven groups:control group (only formalin injection in the submucosa of the rectum,F group);0.25%Lidocaine, 0.125%Lidocaine, saline intracutenous-injection in or out of the experimental area(F-0.25%L-IN, F-025%L-OUT, F-0.125%L-IN, F-0.125%L-OUT, F-S-IN, F-S-OUT group respectively). Pain for each group were assesed every 15 minutes in an one-hour period. Spinal Fos positive neurons were identified by the immunohistochemical technique 1 hour after formalin injection. Results:There was no significant changes in pain scores in the first time period for all groups(P>0.05), but there was significant difference in the later 30 minutes between F group and F-0.25%L-IN, F-025%L-OUT, F-S-IN groups (P<0.01). There was no difference between F group and F-0.125%L-IN, F-0.125%L-OUT, F-S-OUT groups(P>0.05). The number of Fos-like immunoreactive (FLI) neurous was reduced in F-0.25%L-IN, F-0.25%L-OUT and F-S-IN group (P<0.01). Conclusion: FLI positive neurons in the spinal dorsal horn may participate in the transmission and modulation of pain.