中文摘要：

目的：观察硫化氢（H_2S）对1型糖尿病大鼠膈肌一氧化氮（NO）含量和诱导型一氧化氮合酶（i NOS）活性的影响。方法：将32只雄性SD大鼠随机分为4组：正常组（NC组）、糖尿病组（DM组）、糖尿病治疗组（DM＋Na HS组）和Na HS对照组（Na HS组）（n=8）。采用一次性腹腔注射链脲佐菌素55 mg/kg制备1型糖尿病大鼠模型,造模成功后第4周起,DM＋Na HS组和Na HS组大鼠腹腔注射Na HS溶液14μmol/kg干预治疗。连续注射5周后,测大鼠空腹血糖值（FBG）和膈肌重量/体重量比（DW/BW）;HE染色观察膈肌显微结构变化;利用NOS分型测试盒测膈肌组织i NOS活性;硝酸还原法测定膈肌组织NO含量;利用RT-PCR和Western blot分别检测膈肌组织i NOS m RNA和蛋白表达。结果：与NC组比较,DM组大鼠FBG显著升高,膈肌显微结构损伤明显,DW/BW下降,膈肌组织i NOS活性和NO含量显著增加,i NOS m RNA和蛋白表达明显增高,Na HS组各项指标差异无统计学意义。与DM组比较,DM＋Na HS组膈肌显微结构明显改善,DW/BW增高,膈肌组织i NOS活性和NO含量明显下降,i NOS m RNA和蛋白表达显著降低。结论：外源性补充H2S可能通过下调膈肌组织i NOS活性和蛋白表达,降低NO含量,进而保护糖尿病大鼠膈肌的功能。

英文摘要：

Objective： To investigate the effects of hydrogen sulfide （H2S） on nitric oxide （NO） content and inducible nitric oxide syn-thase （iNOS） activity in diaphragm from type 1 diabetic rats. Methods： Thirty-two male SD rats were randomly divided into four groups： normal control group （NC）, diabetes mellitus group （DM）, DM treatment group （DM ＋ NariS） and Naris control group （NariS） （ n = 8）. Rats were treated with streptozotocin 55 mg/kg by intraperitoneal injection to establish type 1 diabetic rat model. The fourth week after the modeling, the rats in the DM ＋ NariS and NariS groups were treated with 14 μmol/kg NariS solution by intraperitoneally injected. After treatment for 5 weeks, fasting blood glucose （FBG） and diaphragm weight （DW）/body weight （BW） were measured. The pathologic＇,d changes of draphragmatic tissues were observed by HE staining. The activity of iNOS was analyzed by spectrophotometric method, while the content of NO was measured by nitric acid reductase method. The iNOS expressions at mRNA and protein levels in diaphragmatic tissues were detected by RTPCR and Western blot respectively. Results： Compared with the NC group, there was no significant difference in the various indexes in the Naris group. While FBG was increased significantly, DW/BW was decreased obviously in the DM group. HE staining revealed obvious changes in diaphragmatic tissues. The activity of iNOS and the content of NO were increased. The levels of iNOS mRNA and protein were increased significantly. Compared with the DM group, DW/BW and pathological damages were improved in the DM ＋ NariS group. The activity of iNOS and NO content were decreased significantly. The levels of iNOS mRNA and protein were decreased obviously. Conclusion： Exogenous H2S can suppress iNOS activity and expression to decrease the content of NO, which improving the capacity of diaphragm in type 1 diabetic rats.