Figure 5. (A) Effects of preconditioning (Pc), halothane (Hal), and halothane + preconditioning on the recovery of the left ventricular negative value of -dP/dt during reperfusion. -dP/dt is plotted as a function of time. Zero time is the beginning of reperfusion. Bars represent SEM. *P < 0.001 for the untreated group (U) compared with preconditioning, halothane, and halothane + preconditioning. No significant difference was found among treated groups. (B) Effects of preconditioning (Pc), isoflurane (Iso), and isoflurane + preconditioning on the recovery of the left ventricular negative value of -dP/dt during reperfusion. -dP/dt is plotted as a function of time. Zero time is the beginning of reperfusion. Bars represent SEM. *P < 0.001 for the untreated group compared with preconditioning, isoflurane, and isoflurane + preconditioning. No significant difference was found among treated groups.