Effect of CSC on CGS21680-mediated inhibition of fMLP-stimulated translocation of PKC, RhoA, and ARF1 to membranes.

Unlabeled neutrophils were prewarmed 5 minutes at 37°C. Neutrophils were then pretreated with 10 μmol/L CB in the presence (A) or absence (B) of 0.1 U/ml ADA for 5 minutes. Where indicated, 0.1 μmol/L CGS21680 (lanes 3, 4, 7, 8) and 10 μmol/L CSC (lanes 2, 4, 6, 8) were also added to the cell suspensions. Neutrophils were stimulated with 0.1 μmol/L fMLP (lanes 5-8) or DMSO (lanes 1-4) for 2 minutes. Incubations were stopped and neutrophil membranes prepared as described in “Materials and Methods.” The levels of PKCα, RhoA, and ARF1 in samples were analyzed by immunoblotting. The data are from 1 experiment representative of 3 similar experiments.