Incubation of cells with cAMP analogs affects SS-induced apoptosis. MpkCCD cells were incubated with 8-cpt-cAMP (100 μM), the EPAC-specific agonist Me-cAMP (100 μM), or vehicle control for 2 h with or without SS. A: representative immunoblots show the levels of the cleaved forms of caspase-3, caspase-7, and PARP (bottom band). B: quantification of log2 ratio of cleaved caspase-3 (ccsp-3), cleaved caspase-7 (ccsp-7), and cleaved PARP (cPARP) from cAMP analog-treated vs. vehicle-treated samples from replicate immunoblots. P values were calculated using paired t-tests. *P < 0.05.