糖尿病大鼠肾脏一氧化氮合酶异构体mRNA表达初步研究

A PRELIMINARY STUDY mRNA EXPRESSION OF NITRIC OXIDE SYNTHASE ISOFORMS IN DIABETIC KIDNEY

目的 :研究糖尿病大鼠肾脏三种一氧化氮合酶异构体mRNA表达。方法 :大鼠随机分成 2组 :单肾切组、糖尿病组。实验第 8周 ,应用RT -PCR技术检测大鼠肾皮质诱生型一氧化氮合酶 (iNOS)、内皮型一氧化氮合酶 (ecNOS)及神经元型一氧化氮合酶 (bNOS)的mRNA表达。并同时检测大鼠肾皮质总一氧化氮合酶(NOS)活性及NO含量。结果 :糖尿病大鼠尿蛋白排泄率较单肾切组明显升高 (P <0 .0 1) ;糖尿病大鼠肾皮质iNOS、ecNOS及bNOS的mRNA表达较单肾切组明显增强 (均P <0 .0 1) ;糖尿病大鼠肾皮质NOS活性也较单肾切组明显增强 (P <0 .0 5 ) ;然而糖尿病大鼠肾皮质NO含量却较对照组大鼠明显降低 (P <0 .0 1)。结论 :糖尿病大鼠肾脏一氧化氮合成障碍 ,灭活加速。

Objective: To investigate mRNA expression of nitric oxide synthase isoforms in diabetic kidney. Methods:The rats were randomly divided by following groups:unmephrectomized (group C) and diabetic rats (group D). At 8 weeks' duration of study, mRNA expressions of inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (ecNOS) and neuronal nitric oxide synthase (bNOS) in renal cortex were measured by quantitative reverse transcription polymerase chain reaction (RT-PCR), respectively. In addition, total nitric oxide synthase activity and NO level of renal cortex were also determined. Results:In group D, urine protein excretion ( P <0.01) and total nitric oxide synthase activity ( P <0.05) were increased obviously in contrast to group C. mRNA expression of iNOS, ecNOS and bNOS in group D were increased, too ( P <0.01) . However, NO level showed a significant decrease in contrast to group C ( P <0.01) .Conclusions:There are impaired production and accelerated breakdown of nitric oxide in the renal cortex of diabetic rats.