Effect of Acute Pentoxifylline Treatment in an Experimental Model of Colitis

Background: The effect of acute pentoxifylline treatment in an experimental model of colitis was assessed using the trinitrobenzene sulphonic acid (TNBS)-induced rat model of colitis.

Methods: Animals were treated with intracolonic injection (250 microliters) of TNBS (50 mg in 50% ethanol) to induce inflammation and ulcers. Animals received pentoxifilline (100 mg/kg intracolonically) or saline 24 and 48 h following TNBS treatment. Five days following TNBS treatment, colons were dissected and scored according to the morphology damage score. The colons were then rolled longitudinally, fixed in formalin and embedded in paraffin. The collagen content of colonic sections were determined by a Sirius red-Fast green technique.

Results: Animals treated with TNBS alone had significantly higher gross morphology damage scores compared to animals treated with saline. Pentoxifylline significantly reduced the gross morphology damage score in animals receiving TNBS. Colonic collagen levels were significantly elevated in TNBS-treated animals compared to animals receiving saline. Pentoxifylline treatment did not alter the collagen content of colons from TNBS-treated animals.

Conclusion: TNBS treatment significantly elevates morphology damage score compared to controls. The results also suggest that colonic collagen was significantly elevated in animals treated with TNBS compared to controls. Pentoxifylline treatment was not sufficient to reduce the elevation in colonic collagen, although pentoxifylline treatment was sufficient to reduce the pathological changes due to TNBS, thus bringing the morphology damage score down to control levels.