Jv. Mombouli et al., ENDOTHELIUM-DERIVED HYPERPOLARIZING FACTOR - A KEY MEDIATOR OF THE VASODILATOR ACTION OF BRADYKININ, Immunopharmacology, 33(1-3), 1996, pp. 46-50
Bradykinin causes vasodilatation by stimulating the production of vaso
dilator prostanoids and nitric oxide (NO). However, there is an additi
onal component that is mediated by a diffusible endothelium-derived hy
perpolarizing factor (EDHF). The non-selective inhibitor of arachidoni
c acid metabolism eicosatetraynoic acid inhibits the EDHF-mediated com
ponent of the relaxation to bradykinin. Therefore, EDHF may be an arch
idonic acid metabolite. The diffusible nature of EDHF has been dispute
d because of the inability to consistently detect the factor using per
fusion bioassay techniques. However, administration of the acyltransfe
rase inhibitor thimerosal facilitates the release of EDHF by endotheli
al cells in culture. Further studies are warranted to identity EDHF an
d explore further its functions in vasomotion.