Figure 1

Blueprint of the histological grading scheme of the increasing severity of ischemia-reperfusion-induced intestinal mucosal lesions. As described by Chiu [26], we graded the intestinal injury as follows: 0, normal villi; 1, development of subepithelial Gruenhagen’s space (black arrow) usually at the apex of the villus, often accompanied by capillary congestion; 2, extension of the subepithelial space with moderate lifting of epithelial layer from lamina propria; 3, marked epithelial lifting down the sides of the villi, a few tips may be denuded; 4, denuded villi with lamina propria and dilated capillaries exposed, increased cellularity of lamina propria may be seen; 5, digestion and disintegration of the lamina propria, hemorrhage and ulceration. Magnification 200 ×; scale bars indicate 50 μm.