Fig. 6.
The role of protein kinases in cer-inducedIKir inhibition. A, Representative traces illustrating the effect of PKC and PKA inhibitors on cer action.Left, Inclusion of PKC (19–36) pseudosubstrate (10 μm) in the pipette solution. Right, Inclusion of PKA inhibitor peptide PKI (5–24) (10 μm) in the pipette solution. B, Summarized data showing that pretreatment of OLGs with wortmannin (5 μm), a PI-3-kinase inhibitor, or inclusion of PKI in the pipette solution did not block the effect of cer. In contrast, inhibition of PKC activity by PKCI or by PKC downregulation with 24 hr PMA treatment significantly attenuated cer-induced IKir inhibition (*p < 0.05 for cer vs PKCI and for cer vs PMA 24 h).
