Effects of thrombin on phosphorylation of PKC isoforms in HPAEC. Confluent HPAEC were treated either with control vehicle or thrombin (0.5 U/ml) for the indicated times, and phosphorylated PKCβ (A), PKCγ (B), PKCε (C), PKCζ (D), PKCθ (E), and PKCδ (F) were detected via immunoblotting. Bar graphs represent relative densitometry of fold changes in phosphorylated PKC isoforms after thrombin relative to vehicle-treated control and expressed as means ± SE from 3 independent experiments. *Significantly different from cells treated with EBM-2 (P < 0.05); #significantly different from cells treated with EBM-2 (P < 0.01).