Expression of matrix metalloproteinases and tissue inhibitor metalloproteinases increases in X-irradiated rat ileum despite the disappearance of CD8a T cells

Figure 7 TIMP expression after X-irradiation with a single dose of 10 Gy. A: In control ilea, TIMP-1 staining was observed in the inflammatory cells of the lamina propria, smooth muscle cells and some rare epithelial cells of the crypt and of the top of the villus (A1, x100). On day one (A2, x100), TIMP-1 staining was found in all layers of the bowel and particularly in epithelial cells and in smooth muscle cells . On day three (A3, x100), the staining spread to the whole tissue. On day seven (A4, x100), TIMP-1 staining was found in smooth muscle cells, epithelial cells of the villus only , in pericryptal myofibroblast sheath and in inflammatory cells of the lamina propria. Gene expression of TIMP-1, determined by real-time RT-PCR was measured in control ilea (C) one (D1), three (D3) and seven (D7) days after X-irradiation respectively. Results are mean±SE, significantly different from controls: ^aP<0.05, ^bP<0.01. B: In control ilea, weak TIMP-2 staining was observed in smooth muscle cells (B1, x100). On day one (B2, x100) and day three (B3, x100) after X-irradiation, a slight TIMP-2 increase was found in smooth muscle cells, in epithelial cells and in inflammatory cells of the lamina propria. On day seven (B4, x100),(C,D) TIMP-2 staining was observed in epithelial cells on the top of the villus, inflammatory cells of the lamina propria. Gene expression of TIMP-2, determined by real-time RT-PCR was measured in control ilea (C) one (D1), three (D3) and seven (D7) days after X-irradiation respectively. Results are mean±SE, significantly different from controls: ^aP<0.05, ^bP<0.01 vs others.