After nitrite is formed in saliva, where does it primarily travel to for further reduction to nitric oxide?

After nitrite is formed in saliva, where does it primarily travel to for further reduction to nitric oxide?

• A. The bloodstream via the gut
• B. The lungs
• C. The pancreas
• D. The bloodstream via the gut

Answer: (D)

The main idea here is that nitrite formed in saliva becomes a circulating reservoir for nitric oxide production. After swallowing, this nitrite is absorbed from the gut into the bloodstream, where it can be reduced to nitric oxide by various nitrite-reducing mechanisms. In the blood and tissues, enzymes and molecules such as deoxyhemoglobin, deoxymyoglobin, and other nitrite reductases convert nitrite to NO, especially under low-oxygen or acidic conditions, helping regulate vascular tone and antimicrobial defenses. This systemic route explains why the nitrite would travel via the gut into the bloodstream for further reduction to NO rather than remaining confined to the stomach or being directed to other organs.

The main idea here is that nitrite formed in saliva becomes a circulating reservoir for nitric oxide production. After swallowing, this nitrite is absorbed from the gut into the bloodstream, where it can be reduced to nitric oxide by various nitrite-reducing mechanisms. In the blood and tissues, enzymes and molecules such as deoxyhemoglobin, deoxymyoglobin, and other nitrite reductases convert nitrite to NO, especially under low-oxygen or acidic conditions, helping regulate vascular tone and antimicrobial defenses. This systemic route explains why the nitrite would travel via the gut into the bloodstream for further reduction to NO rather than remaining confined to the stomach or being directed to other organs.