急性缺氧对大鼠肾组织一氧化氮合酶基因表达的影响

Effects of acute hypoxia on gene expression of nitric oxide synthase in rat kidney

目的了解急性缺氧后大鼠肾组织一氧化氮合酶（ＮＯＳ）基因表达的变化，探讨急性缺氧引起肾损害的分子机制。方法１５只雄性Ｗｉｓｔａｒ大鼠随机分成对照组、缺氧后１０ｍｉｎ组、缺氧后４ｈ组。实验组大鼠在低压舱内模拟上升至５０００ｍ、停留４５ｍｉｎ，出舱后分别在１０ｍｉｎ、４ｈ处死大鼠取肾，提取总ＲＮＡ，用反转录聚合酶链反应（ＲＴ－ＰＣＲ）定量检测大鼠肾组织内ｂＮＯＳｍＲＮＡ、ｅＮＯＳｍＲＮＡ、ｉＮＯＳｍＲＮＡ的表达水平。结果ｂＮＯＳｍＲＮＡ在急性缺氧后１０ｍｉｎ明显下降，４ｈ后恢复正常；ｅＮＯＳｍＲＮＡ急性缺氧后１０ｍｉｎ、４ｈ无明显变化；ｉＮＯＳｍＲＮＡ急性缺氧后１０ｍｉｎ无变化，至４ｈ则无基因表达。结论急性缺氧可导致大鼠ｂＮＯＳｍＲＮＡ、ｉＮＯＳｍＲＮＡ表达下调，ＮＯ在急性缺氧的病理生理过程中起到重要作用。

Objective To explore the molecular mechanism of effect of acute hypoxia on kidney. Methods Fifteen Wistar rats were randomly divided into 3 groups(n=5): 1 control group and 2 experimental groups. The experimental groups underwent 5 000 m altitude exposure in hypobaric chamber for 45 min , and kidneys were taken out in an experimental group 10 min after exposure, and in another 4 h after exposure. The total mRNA was isolated by single step acid guanidinium thiocyanate phenolchloroform extraction method. The mRNA expression level of nitric oxide synthase(NOS) in rat kidney was measured by quantitative reverse transcription polymerase chain reaction (RTPCR). Results The bNOS mRNA expression level in the 10 min group was significantly lower than that of control group, while in the 4 h group, it remained unchanged as compared with that of control group. The eNOS mRNA expression level was not changed both in the 10 min group and the 4 h group. The iNOS mRNA expression level was not changed in 10 min group and there was no gene expression in 4 h group. Conclusions Acute hypoxia may inhabit bNOS mRNA,iNOS mRNA expression in kidney, NO may play an important role in pathophysiological process of hypoxia.