FIGURE 6.

RCE-induced relaxation of aortic rings is mediated by ATP-gated potassium channel activity. Endothelium-intact rings were incubated with cumulative doses of sumac in the absence (RCE; circles) or presence of (A) 10 μM of glibenclamide, an ATP-sensitive potassium channels blocker (Glib + RCE; squares) or (B) tetraethylammonium (100 μM), a non-selective inhibitor of Ca²⁺-sensitive potassium channels (TEA + RCE; squares). Data represent mean ± SEM (n = 7 for glibenclamide or TEA experiments). p < 0.05 for RCE alone versus Glib + RCE and p> 0.05 for RCE only against RCE + TEA.