<i>in vivo</i> MARCKS knockdown decreased VSMC proliferation after transmural aortic injury.

<p>The murine infrarenal aorta was subjected to mechanical injury. <b>A.</b> Topical application of MARCKS siRNA in a 30% pluronic gel suspension at the time of injury resulted in decreased vascular remodeling as determined by wall thickness as shown in H&E staining and fluorescent immunostaining. <b>B.</b> Topical treatment with MARCKS siRNA at the time of injury prevented vessel wall thickening. <b>C.</b> The decreased wall thickness was due to a decrease in VSMC proliferation as determined by staining with DAPI. Cell proliferation was quantified by measuring the number of DAPI stained nuclei per mm² (p<0.05). <b>D.</b> Additionally both BrdU staining and Ki-67 staining (data not shown) confirmed that there were fewer proliferating cells in the media after treatment with MARCKS siRNA. Scale bar = 10 μm. <b>E</b>. MARCKS knockdown resulted in significantly fewer cells per mm² that stained poisitive for BrdU compared to aortas treated with non-targeting, control siRNA. Statistical significance was determined by the two-tailed Student’s <i>t</i>-test. *denotes <i>p</i><0.05. <b>F</b>. Sections of the aortic wall had little staining with pre-immuned rabbit IgG. <b>G</b>. Treatment with DNase I resulted in increased non-specific staining of the aorta. The aortas in Figure A were not pre-treated with DNase I, however the sections in Figure D were treated with DNase I which explains the increase in background signal in Figure D.