title: The nature of endothelium-derived vascular relaxant factor.
abstract: The existence of endothelium-derived vascular relaxant factor (EDRF) was postulated by Furchgott and colleagues when they observed that acetylcholine paradoxically relaxed preconstricted aortic strip preparations by an endothelium-dependent mechanism. This phenomenon has since been demonstrated in different blood vessels and mammalian species and it can be elicited by several other agents. EDRF has been thought to be a humoral agent, a lipoxygenase derivative and possibly a free radical. In the study reported here, by using aortic preparations from the rabbit, alone and in cascade experiments with isolated perfused coronary preparations, we demonstrate definitively that EDRF is a humoral agent. It is released from unstimulated aortic preparations containing endothelium, its release can be stimulated for prolonged periods by acetylcholine, and it is not a lipoxygenase derivative or free radical but an unstable compound with a carbonyl group at or near its active site.
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001013:Aorta, Thoracic / Q000502:physiology*; D000001:Calcimycin / Q000494:pharmacology; D004727:Endothelium / Q000187:drug effects / Q000502:physiology; D007700:Kinetics; D009119:Muscle Contraction / Q000187:drug effects; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000502:physiology; D009569:Nitric Oxide; D010477:Perfusion; D011817:Rabbits; D012701:Serotonin / Q000494:pharmacology; D014665:Vasodilator Agents
chemical_list: D014665:Vasodilator Agents; D009569:Nitric Oxide; D012701:Serotonin; D000001:Calcimycin; D000109:Acetylcholine