摘要
目的观察NG-硝基-L-精氨酸甲酯(L-NAME)对实验性自身免疫性心肌炎(EAM)Lewis大鼠模型的治疗效果,并探索可能的治疗机理。方法 20只Lewis大鼠建立EAM动物模型:双足底注射心肌C蛋白片段和完全弗氏辅佐剂的油状混合物,腹腔注射百日咳毒素。大鼠随机等分为治疗组和模型对照组,每组各10只。治疗组腹腔注射5 mg·kg-1·d-1L-NAME,从免疫注射术后第1天开始连续20 d,1次/d。对照组相同时间内给予相同剂量生理盐水腹腔注射。治疗结束后第1天处死动物,心脏取材,进行系列检测。其中组织病理学石蜡切片苏木素-伊红(HE)染色检测心肌炎症分级,免疫组织化学染色检测T淋巴细胞浸润,天狼星红染色检测心肌胶原纤维含量,硝酸还原酶法检测NO水平,明胶酶谱法检测胶原酶活性。结果与对照组比较,L-NAME治疗组心肌炎症级别下降[(3.42±0.31)vs(2.51±0.22),P<0.01]、T淋巴细胞浸润数目减少[(28.2±4.6)vs(13.2±1.9),P<0.01]、心肌间质纤维化级别下降[(2.33±0.26)vs(1.14±0.17),P<0.01]、血清NO水平降低[(68.34±8.61)μmol/L vs(45.71±6.53)μmol/L,P<0.01],明胶酶活性降低[(254 526±4 729)vs(184 712±3 869),P<0.01]。结论 L-NAME抑制EAM病理发展过程,其机制可能与通过降低NO水平和明胶酶活性,从而降低心肌炎症细胞浸润,延缓心肌间质纤维化有关。
Objective To investigate the therapeutic effect of NG-nitro-L-arginine methyl ester（L-NAME）on experimental autoimmune myocarditis（EAM） in Lewis rats, and to explore the possible therapeutic mechanism.Methods Twenty EAM Lewis rats were treated by injection of myocardial C protein emulsified in completed Freund adjuvant in double footpad and intraperitoneal injection of pertussis toxin. EAM Lewis rats were divided into the treatment group and control group（each with 10 cases）. In the treatment group, the treatment protocol was intraperitoneal administration of L-NAME（5 mg·kg^-1·d^-1） after immunization for 20 days. While in control group the same dose of normal saline was intraperitoneally injected in the same period of time. After experiment at the designate time point, the rats were euthanatized, and their hearts were harvested and tested. Paraffin sections were used for hematoxylin and eosin（HE） stain to determine the inflammation score, for immunohistological stain to determine the infiltration of T lymphocytes, and for picrosirius stain to determine fibrosis score and collagen content. Nitrate reductase method was used to detect serum NO level and gelatin zymography assay to detect the activity of gelatinase. Results The inflammation score in cardiac paraffin slides [（3.42±0.31） vs（2.51±0.22）, P0.01], infiltration of T lymphocytes [（28.2±4.6） vs（13.2±1.9）, P0.01], myocardial interstitial fibrosis score [（2.33 ± 0.26） vs（1.14 ± 0.17）, P0.01], serum NO level [（68.34 ± 8.61） μ mol/L vs（45.71±6.53） μmol/L, P0.01] and activity of gelatinase [（254 526±4 729） vs（184 712±3 869）, P0.01] in treatment group were all significantly lower than in control group. Conclusion L-NAME plays an important role in the pathogenesis of autoimmune myocarditis, and its mechanism may be related to the decrease of serum NO level and gelatinase activity in decreasing myocardial inflammatory cells infiltration and delaying myocardial interstitial fibrosis.
出处
《海南医学》
CAS
2015年第1期11-15,共5页
Hainan Medical Journal
基金
中国人民解放军总医院临床科研扶持基金(编号:2012FC-TSYS-2024)
海南省医学普通科研立项课题(编号:琼卫2012PT-66)
三亚市医疗卫生科技创新项目(编号:YW1306)
