FIGURE 7.

Impact of PKC isoform-specific knockdown on PMA inhibition of cAMP-stimulated Isc. T84 cell monolayers grown to confluence on Transwell supports (6.5-mm insert diameter) were uninfected or infected with shLacZ-, shPKCα-, shPKCδ-, or shPKCϵ-adenovirus (m.o.i. = 30) for 72 h, respectively. The procedure for Isc measurement was carried out as described under “Experimental Procedures.” The cells of each group were exposed to vehicle (solid line) or 100 nm PMA (dashed line) for 1 h and then exposed to 10 μm forskolin (FSK). The Isc (μA/cm²) was measured every 5 min before and after FSK exposure. The data shown here were obtained from uninfected control cells (A), non-targeting shLacZ-adenovirus transduced cells (B), shPKCα-adenovirus transduced cells (C), shPKCδ-adenovirus transduced cells (D), and shPKCϵ-adenovirus transduced cells (E), respectively. F, summary of % inhibition of FSK-stimulated Isc by PMA at 15 and 20 min FSK exposure. The data are presented as mean ± S.E. % of inhibition of Isc by PMA.