益肾固精方改善早期糖尿病肾病大鼠蛋白尿机制探讨

Study of the mechanism of preventing proteinuria by Yishen Gujing Decoction(YSGJD) in early diabetic nephropathy

目的 探讨中药益肾固精方对大鼠早期糖尿病肾病 (DN)蛋白尿的防治及可能机制。方法 将雄性SD大鼠随机分为正常组、对照组及中药治疗组 3组 ,对照组、中药治疗组以腹腔注射STZ造模 ,正常组注射等量缓冲液。益肾固精方 ,浓煎汁 ,大鼠灌胃用药 ,1次 /d ,对照组用自来水。 8周后检测空腹血糖、2 4h尿蛋白总量 ,酶免法测血一氧化氮 (NO) ,放免法检测肾组织cGMP ,逆转录半定量聚合酶链式反应 (RT PCR)分析肾组织iNOSmRNA基因表达。结果 8周后糖尿病大鼠 2 4h尿蛋白总量、肾组织cGMP、iNOSmRNA基因表达均明显高于正常组 (P <0 .0 1) ,与对照组相比 ,中药治疗组 2 4h尿蛋白总量明显减少 (P <0 .0 5 ) ,肾组织cGMP含量明显降低 (P <0 .0 5 ) ,iNOSmRNA基因表达亦明显减低 (P <0 .0 5 )。中药组空腹血糖、血NO较对照组有所下降 ,但无明显差异 ( P >0 .0 5 )。结论 益肾固精方在血糖无明显降低的情况下明显减少早期糖尿病肾病大鼠尿蛋白排出 ,在血NO无明显降低的情况下减少肾组织cGMP含量 ,并纠正了升高的iNOSmRNA的表达 ,推测干扰NO的作用可能是其机制之一。

Objective To study the mechanism of preventing proteinuria by traditional Chinese medicine YSGJD in early diabetic nephropathy (DN) in rats. Methods The male Sprague Dawley (SD) rats were randomly divided into three groups: normal control, untreated control and treated groups.Experimental diabetes mellitus (DM) was induced in untreated control and treated rats with streptozotocin(STZ),and the normal group was given equal buffer solution. The treated rats were given YSGJD daily. The other two groups were given running water. Eight weeks later,the rats were raised in metabolic cages for 24 hours. Then, the 24h urinary protein, serum glucose and nitric oxide(NO) were measured. In the renal cortex, the levels of iNOS mRNA and cGMP were determined by reverse transcription polymerase chain reaction (RT PCR) and radioimmunoassay separately. Results Compared with normal control, in DN rats, the 24h urine protein, the levels of renal cortex iNOS mRNA and cGMP were increased significantly(P<0.01).All above in treated group were reduced than in untreated control(P<0.05). The serum glucose and NO were increased in DN rats than in normal control(P<0.01),and had a little decrease in the treated group,with no significance between untreated and treated groups. Conclusion This recipe can diminish the urine protein in early DN without the significant decrease of serum sugar, can correct the abnormal levels of iNOS mRNA and cGMP in renal cortex. Interfering with the function of NO may be one of its mechanisms.