['Non-alcoholic steatohepatitis (NASH) is a metabolic disorder of the liver, which may evolve to fibrosis or cirrhosis. Pentoxifylline (PTX) has been postulated to act as an antifibrogenic agent able to inhibit hepatic stellate cell proliferation and collagen synthesis in vitro. Short-term studies suggest beneficial effects of PTX in experimental models of NASH.', 'To study whether PTX can influence liver fibrogenesis in an animal model of NASH.', 'To induce NASH, a choline-deficient diet (CDD) was given to Sprague- Dawley rats for 8 weeks. Rats were allocated to two experimental groups one receiving PTX (9 mg/kg/day) in drinking water. Control rats received a choline-supplemented diet. Biochemical and histological evaluation of fatty liver was performed by conventional techniques. In addition, mRNA levels of Pro-collagen I and transforming growth factor beta-1 were assessed by semi-quantitative RT-PCR and stellate cell activation by alpha-actin immunofluorescence stain.', 'After 8 weeks CDD induced a marked elevation of serum aminotransferases, a marked decrease in both hepatic and biliary glutathione and a severe fatty liver infiltration with mild histological inflammation and fibrosis. A significant increase in mRNA levels of both Pro-collagen I and TGFbeta-1 was seen after CDD feeding. No differences were seen between rats receiving PTX and rats on CDD diet alone with regard to the biochemical, morphological or molecular alterations induced by the CDD.'] Does pentoxifylline prevent neither liver damage nor early profibrogenic events in a rat model of non-alcoholic steatohepatitis?