Fig. 3. Concentration–response curves to levcromakalim in the absence or in the presence of lidocaine or mexiletine (10−4m) in combination with Gö 6976 (3 × 10−7m), obtained in the porcine coronary artery without endothelium. * Difference between control rings and rings treated with lidocaine or mexiletine is statistically significant ( P < 0.05). Only in the arteries treated with mexiletine, Gö 6976 significantly restored vasorelaxation induced by levcromakalim (# P < 0.05).