Fig. 2.
PKD activity is dependent on a PKC signaling pathway.
Washed human platelets (1 × 109/mL) were treated with indomethacin (10 μM) and apyrase (2 U/mL) and then stimulated (+) with PMA (30 nM), convulxin (12 nM), and thrombin (0.1 U/mL). PKD was then immunoprecipitated from lysed platelets using the sc937 antiserum. PKD activity was determined by in vitro kinase assay (IVK). As indicated, Ro 31-8220 (1 μM) was either added to the platelets prior to treatment with agonist (IVK) or added directly to the IVK assay. PKD activity in the immunocomplexes was measured by syntide-2 phosphorylation. Results are the average of 3 experiments (each in duplicate) and show the mean ± SEM for each agonist.