Development of acute inflammation in the distal colon in WT and TRPV1
mice. (A) Hematoxylin and eosin (H&E) staining of the distal colon in rats with intracolonic vehicle (Control) and 2,4,6-trinitrobenzene sulfonic acid (TNBS) treatment in wild-type (WT) and transient receptor potential vanilloid 1 knockout (TRPV1−/−) mice (20X). In the groups with TNBS treatment please note the signs of colonic inflammation and tissue damage including sites of hemorrhage, infiltration and disruption of the colonic crypts (c). (B) Concentration of myeloperoxidase (MPO) enzyme in the distal colon in mice with and without active colonic inflammation. (C) MPO activity in the urinary bladder is unchanged by experimental colitis. *P ≤0.05 to respective control.