Key factors in developing the trinitrobenzene sulfonic acid-induced post-inflammatory irritable bowel syndrome model in rats

Table 3 Criteria of histological scoring in colon tissue

Variables	Severity and scoring
	0	1	2	3
Ulceration	No ulcer	Ulcerations not exceeding lamina muscularis mucosae	Ulcerations not exceeding submucosa	Ulcerations exceeding submucosa
Edema	Normal thickness	Submucosal expansion < 30%	Submucosal expansion 30%-100%	Submucosal expansion > 100%
Inflammatory cells	No infiltration	Few scattered cells	Distributed but not dense	Dense
Fibroplasia	Normal collagen	Increase < 30%	Increase 30%-50%	Increase > 50%