Recent advances in endothelium-derived hyperpolarizing factor research
- VernacularTitle:内皮超极化因子的研究进展
- Author:
Wenli WEI
;
Yongyuan GUAN
;
Jiajun SUN
- Publication Type:Journal Article
- Keywords:
endothelium-derived hyperpolar- izing factor (EDHF);
endothelial cells;
Ca2+-acti- vated K+ channels
- From:
Chinese Pharmacological Bulletin
1998;0(S1):-
- CountryChina
- Language:Chinese
-
Abstract:
Endothelium-derived hyperpolarizing factor (EDHF) is the third factor released by en-dothelial cell other than NO and PGI2. It relaxes smooth muscle accompanied by a hyperpolarization in the membrane potential. EDHF may be epoxye-icosatrienoic acids (EETs) formed from arachidon-ic acid by the action of cytochrome P450. It is synthesized and/or released by endothelial cell as a result of an cytosolic Ca2+ increase, which is stimulated by the action of acetylcholine or bradykinin on endothelial cell. EDHF is shown to activate Ca2+-activated K+ channels and induce a hyperpolarization in the membrane potential in vascular smooth muscle. The hyperpolarization of the membrane inhibits the opening of voltage-dependentcalcium channels, allows calcium sequestration and removal mechanisms to lower intracellular calcium, and leads smooth muscle to relaxation. In large conducing arteries, EDHF may provide a secondary system to NO, which assumes primary importance in endothelium-dependent relaxation and inhibits the release of EDHF. However, in small resistance arteries, EDHF appears to be a major determinant of vascular calibre, and may be of primary importance in the regulation of vascular resistance.
