FIG. 7.
Sfrp4 suppresses cell proliferation and collagen production after ischemia. (A) BrdU incorporation during day 3 to 4 after LAD ligation. About 2.5 × 106 cubes of empty polyhedra (empty-PH), or 2.5 × 106 cubes of S-PH were injected into ischemic border areas just after LAD ligation. BrdU was administered at day 3. The border between the acellular scar and cellular areas is shown by dotted black lines. Cubes visible in the bottom of the photo are S-PH in the ischemic border area. The mean and standard deviations of the number of BrdU-positive cells are indicated in the figure. (B) Vascular density in the ischemic border area of PBS- or Sfrp4-treated hearts. The number of von Willebrand Factor-expressing vessel-like structures in border areas of PBS- or Sfrp4-treated rats 3 days after LAD ligation. Means and standard deviations of vascular density (vessels per mm2) are shown in the figure. Red arrows indicate von Willebrand Factor-positive vessel-like structures. Black line framed area in upper photo is magnified and shown (indicated as block arrow) in lower photo. (C) Transcript levels of the β-catenin effector gene TCF4, the TCF4 target cyclin D2, and collagen IIIa (Col IIIa) from PBS or 20 μg Sfrp4-treated ischemic border areas 3 days after ischemic heart injury as determined by qRT-PCR. Values were normalized by the expression of glyceraldehyde 3-phosphate dehydrogenase (rat glyceraldehyde 3-phosphate dehydrogenase as 10,000). The bar and error bar show mean and standard deviations of three rat heart samples, respectively. p-Values for differences in mean values for PBS- or Sfrp4-treated tissues are indicated in the figure.