Figure 2: Gross, Cellular, and Molecular Remodeling 3 Months PMI

(A) Gross images of sham heart, whole organ (left), and cross section (right) of mid-myocardium. (B) Gross images of 12-week PMI heart, whole organ (left), and cross section of mid-myocardium (right). (C) Scar size analysis showing viable (white) and scar tissue (black) as a percentage of total myocardial volume at 12 weeks PMI. (D) Bright-field images were taken of Masson’s trichrome–stained mid-myocardial cross sections of the infarct zone (IZ), border zone (BZ), and remote zone (RZ) of a 3 months PMI animal. The 10× (outside images) and 40× (interior images) were acquired to demonstrate fibrosis and the deposition of collagen in the AW and LW of the PMI animal. (E) Heart weight-to-body weight (HW/BW) ratio. (F) Myocyte cross-sectional area calculated from the 2 viable zones (border zone [BZ] and remote zone [RZ]) in sham animals versus 3 months PMI animals. The images represent the BZ in the sham group (F1) and the 3 months PMI group (F2). Large image is 20× and small image (top right corner) is 40×. Data are shown as the mean by anatomic region in the graphs below. (G) Animals underwent sham (n = 6) or MI (n = 6) procedure, and terminal studies were performed at 3 months ± PMI. Tissue was collected for molecular analysis. Protein was isolated and fractionated into cytosolic (C) and membrane (M) fractions. Percentage of membrane-bound fraction over the cytosolic fraction is shown. *p ≤ 0.05; ***p ≤ 0.005 versus sham. Large scale bar = 100 μm. Small scale bar = 50 μm. 3 months PMI = 3-month’s post-myocardial infarction; other abbreviations as in Figure 1.