Membrane-permeable cAMP analogs and phosphodiesterase inhibitors increase Isc. A) Summary of concentration-response of Isc to 8-Br-cAMP (n = 3–4) on both sides after prior application of 10 μM apical amiloride, EC50 = 180 μM and Hill coefficient 3.0. B) Summary of response of Isc to 8-pCPT-cAMP (8-pCPT; 100 μM; n = 4) on both sides in the presence of apical amiloride (10 μM); no further stimulation by subsequent forskolin (FSK, 10 μM). C) Summary of response of Isc to 3-isobutyl-1-methylxanthine (IBMX; 250 μM; n = 3) on both sides and D) RO-20-1720 (RO-20; 100 μM; n = 3) on both sides after prior application of apical amiloride (10 μM). Summary data are mean ± SEM; *, P < 0.05; NS, not significant; compared to bar immediately to the left.
Pondugula et al. BMC Physiology 2013 13:6 doi:10.1186/1472-6793-13-6