中文摘要：

目的 探讨弓状核含2B亚基的NMDA受体（NR2B）在大鼠炎性痛形成中的作用.方法 雄性SD大鼠108只,体重200～ 250 g,9周龄,采用随机数字表法,将其分为4组：假手术组（S组,n=47）、炎性痛组（IP组,n=47）、二甲基亚砜对照组（DMSO组,n=7）和NR2B拮抗剂Ro25-6981组（Ro25-6981组,n=7）.采用大鼠左侧后肢足垫皮内注射完全弗氏佐剂（CFA）0.1 ml的方法制备炎性痛模型.Ro25-6981组于造模后第3天弓状核内注射Ro25-6981 400 pmol.取7只大鼠,分别于CFA注射前1 d（T1）、注射后第2天（T2）、第3天给药前30 min （T3）、第3天给药后30 min（T4）和第5天（T5）时测定机械缩足反应阈（MWT）和热缩足潜伏期（TWL）.S组和IP组于T11-3、T5时处死大鼠,取弓状核组织,采用RT-PCR法测定NR2B mRNA的表达水平,采用Western blot法检测NR2B、磷酸化NR2B（p-NR2B）的表达水平.结果 与S组比较,IP组、DMSO组和Ro25-6981组T2-5时MWT降低,TWL缩短,IP组各时点p-NR2B表达上调（P＜0.05）,NR2B及其mRNA表达差异无统计学意义（P＞0.05）;与IP组比较,Ro25-6981组T4时MWT升高,TWL延长（P＜0.05）,DMSO组各时点MWT和TWL差异无统计学意义（P＞0.05）.结论 弓状核NR2B的活化参与了大鼠炎性痛的形成.

英文摘要：

Objective To investigate the role of 2B subunits-containing N-methyl-D-aspartate receptors （NR2B） in the arcuate nucleus in the development of inflammatory pain （IP） in rats.Methods One hundred and eight male Sprague-Dawley rats, aged 9 weeks, weighing 200-250 g, were randomly divided into 4 groups using a random number table： sham operation group （group S, n =47）;group IP （n =47）;dimethyl sulfoxide control group （group DMSO, n =7）;selective NR2B antagonist Ro25-6981 group （group Ro25-6981, n=7）.IP was induced by injecting complete Freund＇s adjuvant （CFA） 0.1 ml into the plantar surface of the left hindpaw.Ro25-6981 400 pmol was injected into the arcuate nucleus at 3 days after CFA injection.Seven rats in each group were selected for measurement of the mechanical paw withdrawal threshold （MWT） and thermal paw withdrawal latency （TWL） at 1 day before CFA injection （T1） and at 2 days after CFA injection （T2）, at 30 min before administration on 3rd day （T3） , at 30 min after administration on 3rd day （T4） , and on 5th day （T5）.In S and IP groups, The rats were sacrificed at T1-3 and T5 , and the arcuate nucleus of the hypothalamus was removed for determination of NR2B mRNA expression （by real-time reverse transcriptase polymerase chain reaction） and NR2B and phosphorylated NR2B （p-NR2B） expression （by Western blot）.Conclusion Compared with group S, the MWT was significantly decreased, and the TWL was shortened at T2-5 in IP, DMSO and Ro25-6981 groups, and the expression of p-NR2B was up-regulated at each time point （P〈0.05） , and no significant change was found in NR2B protein and mRNA expression in group IP （P〉0.05）.Compared with group IP, the MWT was significantly increased, and the TWL was prolonged at T4in group Ro25-6981 （P〈0.05） , and no significant change was found in MWT and TWL at each time point in group DMSO （P〉0.05）.Conclusion The activation of NR2B in the arcuate nucleus is involved in the development of IP i