Blood and Tissue Nitric Oxide Products: Formation and Physiological Significance

Recent research indicates that the conventional understanding of nitric oxide (NO) biochemistry is incomplete, highlighting additional pathways involving NO-derived metabolites like S-nitrosothiols (RSNOs) and metal nitrosyls. While RSNOs have been extensively studied, their stability and relevance outside of blood circulation remain unclear. The study reveals that NO-derived products are dynamic with short lifetimes, closely linked to tissue oxygenation and redox states. Notably, tissue nitrite can act as a significant source of NO during hypoxia. These insights broaden our comprehension of NO’s role in vivo and pave the way for future investigations into nitrosative events in biological signaling.