Figure 3: Chronic insulin treatment suppresses baseline expression of PTP1B in dedifferentiated vascular smooth muscle cells. Cells were incubated with serum-free medium for 24 hours followed by stimulation with different concentrations of insulin (5, 10, 20, 50, 100nM) for 24 hours. PTP1B protein levels were checked by Western blot directed against PTP1B. Membranes were reprobed with anti-a-actin to serve as a loading control. Upper panel shows the representative Western blot. Graph shows mean±SE of the ratio of PTP1B to a-actin from three independent experiments. Data were analyzed by using One-Way ANOVA followed by post hoc test. *P<0.05, compared to control.