Ascorbate mediates the non-enzymatic reduction of nitrite to nitric oxide.

ABSTRACT: Nitric oxide (NO^•) generated by nitric oxide synthases is involved in many physiological and pathophysiological processes. However, non-enzymatic formation of NO^• also occurs in vivo. Here we investigated the production of NO^• from nitrite, as facilitated by ascorbate, over the pH range of 2.4-7.4. Using a nitric oxide electrode, we observed at low pH a rapid generation of NO^• from nitrite and ascorbate that slows with increasing pH. The formation of NO^• was confirmed by its reaction with oxyhemoglobin. In the ascorbate/nitrite system a steady-state level of NO^• was achieved, suggesting that a futile redox cycle of nitrite-reduction by ascorbate and NO^•-oxidation by dioxygen was established. However, at pH-

SUBMITTER: Du J 

PROVIDER: S-EPMC10486277 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature