Xanthine oxidase inhibitor in acute experimental pancreatitis in rats and mice.

It has been suggested that oxygen-derived free radicals play a decisive role in the pathogenesis of acute experimental pancreatitis in a model of edematous pancreatitis. Accordingly, allopurinol, a xanthine oxidase inhibitor, was shown to mitigate the development of nonfatal acute pancreatitis in ex vivo perfusion models using dogs. For further evaluation of allopurinol, its effect was studied in two forms of fatal necrotizing acute experimental pancreatitis: sodium taurocholate-induced pancreatitis in rats and choline-deficient ethionine-supplemented diet-induced pancreatitis in mice. Allopurinol did not affect the mortality rate, pancreatic enzyme elevation in serum and ascites, the enzyme content of the pancreas, or any parameter indicating histopathological damage in the pancreas. Although these experiments did not determine the role oxygen-derived free radicals play in the development of pancreatitis, they show, none the less, the absence of any beneficial therapeutic effect of a xanthine oxidase like allopurinol on the development of the disease once it has begun.