Fig. 3. Effect of halothane and sevoflurane on maximum force normalized for cross-sectional area in neonatal versus adult cardiac muscle. Data are expressed in absolute force (A and C ), and relative to control values (B and D ). *Indicates significant difference between ages (P < 0.05; n = 12 for controls, and n = 6 for all other groups). †Indicates a significant difference between control and halothane groups. ‡Indicates a significant difference between 1 and 2 minimum alveolar concentration (MAC) anesthetic. Note the considerably smaller effect of sevoflurane.