GYY4137-induced relaxation of phenylephrine-preconstricted mesenteric artery rings.

Effect of increasing concentrations of GYY4137 on mesenteric artery segments with intact or removed endothelium was examined in the absence or in the presence of K+ channel inhibitors and Rmax and EC50 values were calculated for each preparation (n = 6/group). ***p<0.001 vs. preparation without K+ channel inhibitors (Student t-test for related variables), †††p<0.001 vs. segments with intact endothelium (Student t-test for unrelated variables). Because glibenclamide almost completely abolished the effect of GYY4137 in endothelium-denuded segments, Rmax and EC50 could not be calculated.