Figure 3. Silencing of Abl gene in mesenteric segments by short hairpin RNA (shRNA).

(A) Blots of protein extracts from untreated arteries (UT) or arteries that had been cultured for 2 days with plasmids encoding luciferase shRNA (Luc) or Abl shRNA (Abl) were probed with antibodies against Abl and α-actin. The level of Abl was lower in arteries producing Abl shRNA than in untreated arteries or segments generating Luc shRNA. Similar amounts of actin were detected in all three samples. (B) Abl/actin ratios in arteries producing Luc shRNA or Abl shRNA are normalized to ratios obtained in tissues not treated with plasmids (n = 5). Values are mean ± SE. *Significantly lower protein ratios in segments producing Abl shRNA compared to untreated arteries or arteries generating Luc shRNA (P < 0.01). (C) Representative images showing green fluorescence protein (GFP) signals observed in the medial smooth muscle layer of the arterial walls treated with plasmids, indicating effective transfection in the smooth muscle layer of arteries. Weak autofluorescence (panel a) was observed from the untreated mesenteric artery (panel a'). GFP signal (panel b) was detected from the artery transfected with plasmids encoding luciferase (Luc) shRNA (panel b'); the fluorescence (panel c), the artery transfected with plasmids for Abl shRNA (panel c'). PC, phase contrast images. A, adventitia; M, media. Intima was removed during preparation. Bar, 15 μm.