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Updated: Jun 23, 2026
11:28
Analytical Techniques for Assaying Nitric Oxide Bioactivity
Published on: June 18, 2012
Nonenzymatic nitric oxide production in humans
1Department of Anesthesiology and Intensive Care, Karolinska Hospital, Stockholm, Sweden.
Nitric Oxide : Biology and Chemistry
|August 26, 1998
Summary
A new pathway for nitric oxide (NO) production in humans has been discovered. This nonenzymatic process involves nitrite reduction under acidic conditions, complementing known synthase pathways.
Area of Science:
- Biochemistry
- Physiology
- Molecular Biology
Background:
- Nitric oxide (NO) is a crucial signaling molecule synthesized primarily by nitric oxide synthases (NOS).
- Biological systems rely on NOS enzymes for the production of NO from L-arginine.
Purpose of the Study:
- To investigate a newly discovered pathway for NO production in humans.
- To understand the conditions and implications of nonenzymatic NO generation.
Main Methods:
- The study focused on the chemical reduction of inorganic nitrite.
- Conditions favoring nonenzymatic NO production were explored, including acidic and reducing environments.
Main Results:
- A novel, nonenzymatic pathway for NO production was identified in humans.
- This pathway occurs under acidic and reducing conditions, such as in the stomach and during ischemia.
- Nonenzymatic NO production was demonstrated in various biological contexts.
Conclusions:
- Nonenzymatic nitrite reduction represents a significant alternative pathway for NO generation.
- This mechanism likely contributes to biological events previously attributed solely to NOS.
- Further research is warranted to fully elucidate the physiological roles of nonenzymatic NO production.
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