nitric oxide

  • EDRF
  • endothelium-derived relaxing factor
  • NO
Biochemistry. A naturally-occurring gas that in the body is a short-lived vasodilator substance. Nitric oxide is produced from arginine by the enzyme nitric oxide synthase. It activates the guanylate cyclase in vascular smooth muscles, leading to an increase of cyclic GMP, which inhibits muscular contraction and produces relaxation (vasodilation).