Fig. 9
Effect of sulfonylureas on complex formation between caveolin, pp59Lyn, and cAMP-binding ectoprotein, Gce1. (140; G. Müller, S. Welte, S. Wied, W. Frick, manuscript submitted). Isolated rat adipocytes were stimulated with increasing concentrations of different sulfonylureas for 30 min at 30°C. Total plasma membranes were prepared by differential centrifugation, solubilized and subjected to immunoprecipitation (IP) with anti-caveolin antibodies. The anti-caveolin immunoprecipitates were immunoblotted (IB; chemiluminescence detection) with specific antibodies for the presence of pp59Lyn and caveolin or photoaffinity-labeled with N3-[32P]cAMP for detection of Gce1. Phosphorimages and chemiluminescence images of a typical experiment (repeated three times with similar results) are shown. The homologous immunoblotting with caveolin demonstrated comparable efficiencies of the anti-caveolin immunoprecipitations under the various conditions.