“In the presence of the endothelium, indomethacin (a nonselective cyclooxygenase inhibitor), methylene blue (cyclic guanosine monophosphate … (L-NAME, nitric oxide synthase inhibitor), tetraethylammonium (TEA, nonselective calcium activator potassium channel blocker), 4-aminopyridine (4-AP, voltage-dependent K+ channel blocker), barium … significant reduction in the vasorelaxation effect induced by resveratrol.”