Fig. 2. (A ) Levobupivacaine (LBV) dose-response curve in isolated endothelium-intact or -denuded aorta. *P < 0.001 versus 10−5M LBV; †P < 0.001 versus endothelium-intact; ‡P = 0.0048, # P < 0.001 versus 10−4M LBV. (B ) Ropivacaine (RPV) dose-response curve in isolated endothelium-denuded aorta. *P < 0.001, †P = 0.0136 versus 3 × 10−5M RPV; ‡P < 0.001 versus 3 × 10−4M RPV. (C ) Mepivacaine (MPV) dose-response curve in isolated endothelium-denuded aorta. *P = 0.0138, †P < 0.001 versus 10−5M MPV; ‡P < 0.001 versus 3 × 10−3M MPV. Data are shown as mean ± SD and are expressed as the percentage of the maximal contraction induced by isotonic 60 mM KCl (100% = 2.41 ± 0.23 g [n = 7] and 100% = 2.79 ± 0.15 g [n = 7] for aortic rings with or without endothelium, respectively in A ; 100% = 3.16 ± 0.47 g [n = 7] for aortic rings without endothelium in B ; 100% = 3.18 ± 0.36 g [n = 7] for aortic rings without endothelium in C ). N indicates the number of rats from which descending thoracic aortic rings were derived.