Structural and molecular features of intestinal strictures in rats with Crohn's-like disease

Figure 2 Thickness of the smooth muscle layers in the colon of control animals and in rats treated three times with 2,4,6-trinitrobenzenesulfonic acid. A: Representative light micrographs of a toluidine blue-stained semithin section from the colon of a control rat; B: TNBS-treated rat on day 120 of the experimental period. Bar: 25 μm. Significant thickening of the LMM (C), CM (D) and LM (E) was demonstrated in the strictured gut wall of the TNBS-treated rats (S) relative to the controls (C) on day 90. Whereas a further significant thickening was measured in the CM and LM on day 120, the thickness of the LMM was similar to that in the controls at this timepoint. Data are expressed as mean ± SE. ^bP < 0.001 TNBS-treated groups vs age-matched controls; ^dP < 0.001 2,4,6-trinitrobenzenesulfonic acid (TNBS)-treated group on day 90 vs TNBS-treated group on day 120. LMM: Lamina muscularis mucosae; CM: Circular muscle layer; LM: Longitudinal muscle layer; MG: Myenteric ganglion.