Tumour necrosis factor α activates a p22phox-based NADH oxidase in vascular smooth muscle
نویسندگان
چکیده
Increasing experimental evidence suggests that non-phagocytic cells express a potent superoxide (O # −d)-producing NADH oxidase that might be related to the phagocytic NADPH oxidase. Here we show that the cytokine tumour necrosis factor α (TNFα) activates, in a timeand dose-dependent manner, a O # −dproducing NADH oxidase in cultured rat aortic smooth-muscle cells. Dose–response experiments for NADH showed an upward shift of the curve for TNF-α-treated cells, suggesting that TNFα increased the amount of available enzyme. Using the anti-sense transfection technique, we further demonstrate that the molecular identity of this oxidase includes p22phox (the α subunit of
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