Effect of decorin administration on AAA development in mice.

<p>(<b>A-B</b>) Immediately after CaCl₂ treatment, Gelfoam patches loaded with PBS (CaCl₂+PBS, n = 9) or 20 (g decorin (CaCl₂+decorin, n = 10) were placed into the periaortic spaces between the left renal vein (lt RV) and bifurcation. AA: abdominal aorta, IVC: inferior vena cava, lt RA: left renal artery. Untreated mice were used as controls (Control, n = 6). The mice were sacrificed 42 days after CaCl₂ treatment. (<b>C</b>) Representative photographs show aortas 42 days after CaCl₂ treatment. (<b>D</b>) Quantitative analysis of the maximum external diameters of abdominal aortas. Data are mean ± SD. **<i>p</i><0.01 compared to Control; ##<i>p</i><0.01 compared to CaCl₂+PBS. (<b>E</b>) Representative histological and immunohistochemical stains of abdominal aorta specimens from mice treated as indicated. HE and EVG stains depict cell nuclei (blue-black) and elastin network (black), respectively. The localization of MMP-9 is indicated with red staining. M: media, A: adventitia. (<b>F</b>) Infiltrating mononuclear cells were counted in five high-power fields. Data are mean ± SD. **<i>p</i><0.01 compared to Control; #<i>p</i><0.05 compared to CaCl₂+PBS. (<b>G-H</b>) The degree of medial layer elastin disruption was graded as mild (grade I), moderate (grade II), high (grade III), or severe (grade IV) based on EVG-stained sections. Yellow arrows indicate disruption of elastic lamellae. White asterisks indicate preserved elastic lamellae.