Figure 3.

Knockdown of PKG decreases the ability of heparin to block DNA synthesis. A7r5 cells were treated with siRNA designed to knock down PKG or non-specific siRNA as described in Methods. After 48 hr, BrdU was added to all cells. Cells were left untreated or treated with PDGF in the presence or absence of 200 μg/ml heparin. Cells were stained with antibodies against PKG (not shown) or antibodies against BrdU followed by appropriate secondary antibodies. Fluorescent intensity as a percentage of the highest intensity sample from the experiment was calculated for each cell. Data from control siRNA-treated cells (black bars) are shown from one experiment run in duplicate (more than 100 cells/treatment). For control siRNA-treated cells (black bars), PDGF treated cells had significantly increased fluorescent intensity compared to controls (p<0.05,*), and these cells also treated with heparin had significantly decreased fluorescent intensity compared to cells treated with PDGF alone (p<0.05,*). Data from two experiments (more than 150 cells/treatment) are shown for PKG siRNA treated cells (grey bars). There were no significant differences in fluorescent intensity between treatments for knockdown cells.