P. mume branch caused endothelium-dependent vasorelaxation in rat aortic rings. - GreenMedInfo Summary

Korean plum ((Siebold) Siebold&Zucc.) has long been used as a health food or herbal medicine in Asia. Previous studies have shown that several plants of the genushave vasodilatory and antihypertensive effects; we hypothesized thatbranches may have a vasorelaxant effect. In this study, we evaluated the effects and action mechanism of 70% ethanol extract ofbranch (PMB) on isolated rat aortic rings. Inhibitors such as NG-nitro-l-arginine methyl ester, 1-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, methylene blue, indomethacin, atropine, tetraethylammonium chloride, glibenclamide, 4-aminopyridine and BaClwere used to investigate the mechanism of vasodilation responsible for the vascular relaxation. PMB (2-30μg/mL) induced vasorelaxation in the presence of vascular endothelium, and all inhibitors used in this study affected the degree of relaxation. These results suggest that the vasorelaxant effect of PMB is endothelium-dependent and affects the nitric oxide-cyclic guanosine monophosphate pathway, prostacyclin pathway, muscarinic receptor pathway, and potassium channels. Our study explains that PMB may be another approach to hypertension treatment to reduce the burden of cardiovascular disease.