| Hu CM |
------>authors3_c= ------>paper_class1=1 ------>Impact_Factor=1.960 ------>paper_class3=2 ------>paper_class2=1 ------>vol=70 ------>confirm_bywho=sylin ------>insert_bywho=sunpowerhu ------>Jurnal_Rank=27.1 ------>authors4_c= ------>comm_author= ------>patent_EDate=None ------>authors5_c= ------>publish_day=1 ------>paper_class2Letter=None ------>page2=28 ------>medlineContent= ------>unit=E0125 ------>insert_date=20090917 ------>iam=1 ------>update_date=None ------>author=??? ------>change_event=4 ------>ISSN= ------>authors_c= ------>score=500 ------>journal_name=Planta Med ------>paper_name=Impairment of Vascular Function of Rat Thoracic Aorta in an Endothelium-Dependent Manner by Shikonin/Alkannin and Derivatives Isolated from Roots of Macrotomia euchroma ------>confirm_date=20090918 ------>tch_id=098012 ------>pmid=14765288 ------>page1=23 ------>fullAbstract=The effects of a naphthoquinone analogue, shikonin/alkannin (SA) and derivatives (acetylshikonin and beta,beta-dimethylacrylshikonin), on vascular reactivity were studied with isolated rat aortic rings. At lower concentrations, SA and its derivatives concentration-dependently inhibit the agonist-induced (acetylcholine and histamine) relaxation in PE precontracted aorta in an endothelium-dependent manner with IC (50) values ranging from 0.2 to 1.5 microM. In addition to the effect on agonist-induced vasorelaxation, the Ca (2+) ionophore A23187-induced vasorelaxation was also inhibited or reversed by SA. However, SA had no effect on sodium nitroprusside-induced (guanylate cyclase activator) vasorelaxation. These data suggested that SA and its derivatives might be acting as inhibitors of nitric oxide synthesis in endothelium. At a concentration greater than 10 microM, SA induced contraction of intact but not denuded aorta which could be inhibited by prior treatment with indomethacin, a cyclooxygenase inhibitor. In summary, the results from this study showed that SA and its derivatives inhibited agonist-induced relaxation at lower concentrations and induced vasocontraction at higher concentrations. All the effects seen with SA were endothelium-dependent, however, through different mechanisms. Abbreviations. SA:shikonin/alkannin PE:phenylephrine Ach:acetylcholine SNP:sodium nitroprusside eNOS:endothelial nitric oxide synthase L-NAME: Nw-nitro- L-arginine methyl ester ------>tmu_sno=None ------>sno=22194 ------>authors2=Cheng YW ------>authors3=Cheng HW ------>authors4=Kang JJ ------>authors5= ------>authors6= ------>authors6_c= ------>authors=Hu CM ------>delete_flag=0 ------>SCI_JNo=None ------>authors2_c= ------>publish_area=0 ------>updateTitle=Impairment of vascular function of rat thoracic aorta in an endothelium-dependent manner by shikonin/alkannin and derivatives isolated from roots of Macrotomia euchroma. ------>language=2 ------>check_flag=None ------>submit_date=None ------>country=None ------>no= ------>patent_SDate=None ------>update_bywho=None ------>publish_year=2004 ------>submit_flag=None ------>publish_month=1 |