Figure 7. UTP-induced PAI-1 expression and cell proliferation are blunted in P2Y₂^−/− mice.

CFs from wild-type or P2Y₂^−/− mice were serum-starved for 24 h and then incubated with UTPγS (10 µM) for 4 h. Cells were assayed by immunoblot analysis to quantify protein expression of PAI-1. (A) Immunoblotting shows that UTPγS increases PAI-1 protein expression in CFs from wild-type mice but not from P2Y₂^−/− mice. Panel (B) shows quantification of the immunoblots from panel (A). The data shown in (B) are the mean ± SEM of at least 3 independent experiments compared by using ANOVA with post-hoc multiple comparison tests. **, p<0.01. (C) CFs from wild-type mice show ~50% increase in proliferation in response to treatment with UTPγS (10 µM) for 24 h but not 48 h. (D) UTPγS is not proliferative in CFs from P2Y₂^−/− at either time point.