RNA silencing in vivo reveals role of p22phox in rat angiotensin slow pressor response
RNA silencing in vivo reveals role of p22phox in rat angiotensin slow pressor response
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DOI：
10.1161/01.hyp.0000200023.02195.73
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发表时间：
2006-02-01
期刊：
影响因子：
8.3
通讯作者：
Wilcox, CS
中科院分区：
文献类型：
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作者：
Modlinger, P;Chabrashvili, T;Wilcox, CS
血管紧张素II（Ang II）慢升压反应引起平均动脉压和活性氧的增加。我们在Sprague道利大鼠体内使用双链干扰RNA（siRNA）来检验这一假设，即NADPH氧化酶的p22（phox）组分的增加是这种反应所必需的。通过遥测从8-异前列腺素前列腺素F-2 α的排泄和血压评估活性氧。在培养的血管平滑肌细胞中，针对p22（phox）的两个siRNA序列（sip 22（phox））使mRNA降低> 85%。在14天的Ang II（200 ng . kg（-1）。min（-1））或假输注。在两组中，sip 22（phox）相对于对照siRNA导致肾皮质中p22（phox）mRNA和蛋白质表达以及NADPH氧化酶活性的显著（P < 0.001;约50%）降低。在血管紧张素II灌注大鼠中，sip 22（phox）降低了Nox-1、-2和-4的蛋白表达，但增加了p47（phox）。在sip 22（phox）后三天，输注Ang II的清醒大鼠具有减少的8-异前列烷排泄（10 +/- 1对19 +/- 2 pg）。24 h（-1）; P < 0.01）和平均动脉压降低（142 +/- 5 vs 168 +/- 4 mm Hg; P < 0.005）。p22（phox）的增加是增加肾脏NADPH氧化酶活性、Nox蛋白表达和氧化应激所必需的，并有助于
The angiotensin II (Ang II) slow-pressor response entails an increase in mean arterial pressure and reactive oxygen species. We used double-stranded interfering RNAs (siRNAs) in Sprague Dawley rats in vivo to test the hypothesis that an increase in the p22(phox) component of NADPH oxidase is required for this response. Reactive oxygen species were assessed from excretion of 8-isoprostane prostaglandin F-2 alpha and blood pressure by telemetry. Two siRNA sequences to p22(phox) (sip22(phox)) reduced mRNA > 85% in cultured vascular smooth muscle cells. Rats received rapid ( 10 second) IV injections ( 50 to 100 mu g) of 1 of 2 different sip22(phox), control siRNA, or vehicle (TransIt in saline) during 14 day SC infusions of Ang II ( 200 ng . kg(-1) . min(-1)) or sham infusions. In both groups, sip22(phox), relative to control siRNA, led to significant ( P < 0.001; approximate to 50%) reductions in expression of p22(phox) mRNA and protein and of NADPH oxidase activity in the kidney cortex. In Ang II - infused rats, sip22(phox) decreased protein expression for Nox-1, - 2, and - 4 but increased p47(phox). Three days after sip22(phox), conscious rats infused with Ang II had a reduced excretion of 8-isoprostane ( 10 +/- 1 versus 19 +/- 2 pg . 24 h(-1); P < 0.01) and a reduced mean arterial pressure (142 +/- 5 versus 168 +/- 4 mm Hg; P < 0.005). An increase in p22(phox) is required for increased renal NADPH oxidase activity, expression of Nox proteins and oxidative stress, and contributes