Sodium Nitrate Attenuates the Acute Antihypertensive and Vascular Effects of Sodium Nitrite by Inhibiting Nitrite-Reductase Activity of Xanthine Oxidoreductse

The antihypertensive effects of nitrite are at least in part attributable to tissue reduction of nitrite to nitric oxide (NO) by xanthine oxidoreductase (XOR). XOR also reduces nitrate to nitrite, however, at a much lower rate than it reduces nitrite to NO. Here, we examined whether nitrate decreases the formation of NO from nitrite by XOR, and therefore attenuates its antihypertensive and vascular effects.