Figure 8.

ATP increases α-SMA and expression of profibrotic markers PAI-1 and MCP-1. A) Immunofluorescent microscopy shows that incubation with 10 μM ATP for 24 h increased expression of α-SMA-containing stress fibers. B) Treatment with 10 μM ATP for 4 h increased mRNA expression of the profibrotic markers PAI-1 and MCP-1 (3.5- and 4-fold, respectively; P<0.05). siRNA knockdown of P2Y₂ expression abolished this effect. C) ERK inhibition with U0126 (U0) eliminated the stimulatory effect of ATP on PAI-1 and MCP-1 expression. Data are presented as means ± se of ≥3 independent experiments. *P < 0.05, **P < 0.01, ***P < 0.001.