Lipid rescue of the epicardial action potential (AP): mepivacaine. (A) A representative train of 150 APs recorded in a left ventricular epicardial cardiomyocyte at 1 Hz under control conditions (blue), with 40 µM mepivacaine (red), and with 40 µM mepivacaine and 10% Lipovenös^® (green). (B) The last APs under each condition are superimposed. (C) The upstroke of the APs shown in B. (D) Mean overshoot of the AP. (E) Maximal upstroke velocity (dV/dt_max) of the AP. (F) AP duration at 50% repolarization (APD₅₀). (G) AP duration at 90% repolarization (APD₉₀). The numbers in the bars give the number of myocytes investigated. Data are given as mean ± SEM. *P < 0.05. **P < 0.01. ***P < 0.001. C = control; dV/dt_max = maximal upstroke velocity of the AP; Lipovenös^® = Lipovenös^® MCT 20% (Fresenius Kabi AG, Bad Homburg, Germany); M = 40 µM mepivacaine; M+L = 40 µM mepivacaine + 10% Lipovenös^®; n.s. = not significant; overshoot = overshoot of the AP; V_m = membrane potential.