Fig. 1. Isoflurane minimum alveolar concentration (MAC) decreases by increasing the concentration of a cyclic guanosine monophosphate (cGMP)–dependent protein kinases Iα inhibitor, Rp-8-p-CPT-cGMPS. Data are presented as the mean ± SEM. n = 8 animals for each dose, except n = 7 for the 200 μg Rp-8-p-CPT-cGMPS. *P < 0.05 versus control; **P < 0.01 versus control; †P < 0.05 versus preceding concentration.