Figure 2: Effect of TSF on the morphologic structure of colon. (a) Wet weight per unit length; (b) HE staining; (c) comparison of wall thickness among groups; (d) comparison of smooth muscle cells number per unit area among groups; (e) collagen III immunostaining in smooth muscle; (f) collagen III immunostaining in mucosa layer; (g) comparison of collagen III contents among groups; (h) comparisons of collagen I contents among groups. Values are expressed as mean (SD), for each group (, compared with DM group). C-muscle: circular muscle layer; DM: diabetic group; IOD: integral optical density; L-muscle: longitudinal muscle layer; NC: normal control group; Sub: submucosa; TSF: Tangshen Formula group.