Figure 1.

Characterization of colonic-ulcer induction in rats by trinitrobenzene sulphonic acid [TNBS] injection. [A] Schematic representation of induction of colonic ulcers in 7-week-old rats via injection of ethanol solution [35%, 0.2 mL] containing 0.15 M TNBS into the colon lumen after clamping the proximal colon using ringed forceps. [B] Time course of the experimental protocol. [C–E] Representative endoscopic [C], macroscopic [D] and histological [E] images [haematoxylin and eosin staining; the magnification of the black box in the upper panel is shown in the lower panel] taken immediately before [0], and 3, 7, 14, 21 and 28 days after TNBS injection. [F–J] Relative ulcer lengths [F, G] and areas [H]. Correlation between relative ulcer length and area [I], and histological score [J] [n = 3–15 per group]. Relative ulcer length was obtained by dividing ulcer girth by colon girth.