Endothelium-derived relaxing factor (EDRF) was the tentative name of what was later discovered to be nitric oxide (NO). It is released by the vascular endothelium in response to a variety of chemical and physical stimuli. It causes the smooth muscle in the vessel wall to relax, resulting in vasodilation.

EDRF was discovered and characterized by Robert F. Furchgott, a winner of the Nobel Prize in Medicine in 1998 with his co-researchers Louis J. Ignarro and Ferid Murad.

Please refer to nitric oxide for a full treatment of the biological functions of NO.

External link

• R.F. Furchgott's website: The Nature of the Endothelium-Derived Relaxing Factor (http://www.hscbklyn.edu/pharmacology/furch.htm)