%0 Journal Article
%T The Vasorelaxant Effects of Anaxagorea luzonensis A. Grey in the Rat Aorta
%A P. Tep-Areenan
%A P. Sawasdee
%J International Journal of Pharmacology
%D 2011
%I Asian Network for Scientific Information
%X The aim of the present research was to study vasorelaxant effects of dichloromethane extract of Anaxagorea luzonensis (CH2Cl2-AL) and its underlying mechanisms. CH2Cl2-AL (1-300 ¦Ìg mL-1) induced concentration-dependent vasorelaxations which were reduced by endothelial denudation, 300 ¦ÌM NG-nitro-L-arginine methyl ester (L-NAME) and a combination of 10 ¦ÌM indomethacin and 300 ¦ÌM L-NAME, but not indomethacin alone. Raising the extracellular KCl concentration to 60 mM inhibited vasorelaxant responses to CH2Cl2-AL in both endothelium-intact and -denuded rings. Moreover, the responses to CH2Cl2-AL were inhibited by 30 ¦ÌM barium chloride, 2 ¦ÌM clotrimazole, 10 ¦ÌM glibenclamide and 10 ¦ÌM 1-[(2-chlorophenyl) diphenylmethyl]-1H-pyrazole (TRAM-34), but not 1 mM 4-aminopyridine. Pre-incubation with CH2Cl2-AL (1-100 ¦Ìg mL-1) inhibited contractions induced by CaCl2 in a Ca2+-free, high KCl buffer. The present findings demonstrate, in the rat isolated aorta, that vasorelaxant responses to CH2Cl2-AL are, in part, mediated via the endothelium and NO-dependent pathways. Moreover, activation of KIR, KCa, KATP channels seems to play a role in CH2Cl2-AL-induced responses. Interestingly, Inhibition of extracellular Ca2+ influx is largely involved in the action of CH2Cl2-AL. The present study provides scientific evidence to support the use of CH2Cl2-AL as a vasodilator agent.
%K Ca2+ influx
%K K+ channels
%K nitric oxide
%K endothelium
%K Anaxagorea luzonensis
%K vasorelaxation
%U http://docsdrive.com/pdfs/ansinet/ijp/2011/119-124.pdf