Nitric oxide (NO) is a colorless, odorless gas that plays a crucial role in various physiological processes. It is a free radical, meaning it has an unpaired electron, which makes it highly reactive. NO is synthesized in the body from the amino acid L-arginine by the enzyme nitric oxide synthase (NOS). It acts as a signaling molecule and is involved in the regulation of blood pressure, immune response, and neurotransmission.
