The vasorelaxation of Antrodia camphorata mycelia: involvement of endothelial Ca(2+)-NO-cGMP pathway.
Antrodia camphorata, a medicinal fungus, has been used to treat cardiovascular diseases such as hypertension for many years. The purpose of this study was to examine the effects of mycelia extracts, from five Antrodia camphorata strains, on vascular tension and underlying mechanisms were explored. In isolated rat aortic rings, accession B86 caused concentration-dependent vasorelaxation with maximal relaxation of 40.34 +/- 7.53% whereas accessions 35398, 35396 and B71 had mild vasorelaxing effects. Strain B85 evoked potent vasorelaxation, partly through an endothelium-dependent mechanism that was inhibited by Nomega-nitro-L-arginine and 1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one (ODQ) but not by antagonist of K+ channels, tetraethylammonium. In cultured endothelial cells, B85 stimulated nitric oxide (NO) release and augmented the level of the intracellular Ca2+ concentration. HPLC and LC-MS-MS analysis revealed the presence of adenosine. Our results suggest that B85 produced strongest vasorelaxation in aortic preparations among five test strains. B85 acts in part on endothelial cells by activating the Ca(2+)-NO-cGMP pathway to reduce smooth muscle tone. However, K+ channels had no apparent roles. Adenosine could possibly be involved in the endothelium-dependent pathway of B85-induced vasorelaxation.
D000241:Adenosine / Q000032:analysis; D001013:Aorta, Thoracic / Q000187:drug effects / Q000378:metabolism; D001487:Basidiomycota / Q000737:chemistry* / Q000145:classification; D002118:Calcium / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism; D066298:In Vitro Techniques; D008516:Medicine, Chinese Traditional; D025282:Mycelium / Q000737:chemistry; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism; D010069:Oxadiazoles / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology*; D010946:Plants, Medicinal; D011810:Quinoxalines / Q000494:pharmacology; D013045:Species Specificity; D019789:Tetraethylammonium / Q000494:pharmacology; D014664:Vasodilation / Q000187:drug effects*; D014665:Vasodilator Agents / Q000494:pharmacology*
C095284:1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one; D010069:Oxadiazoles; D010936:Plant Extracts; D011810:Quinoxalines; D014665:Vasodilator Agents; D009569:Nitric Oxide; D019789:Tetraethylammonium; D006152:Cyclic GMP; D000241:Adenosine; D002118:Calcium; D019331:NG-Nitroarginine Methyl Ester