An altered adaptive response of the pancreas and small intestine to nutritional stress has an adverse impact upon nutritional status in elderly humans or senescent rats. We evaluated the effects of a pancreatic extract nutritional supplement on intestinal mucosa adaptation in LPS-treated aged rats. Endotoxemic rats were starved for 48 hr and then refed ad libitum for four days with a standard diet. Afterwards they received, over one week, the standard diet enriched with either pancreatic extract (PE) (2.4 g/day) or casein (isonitrogenous to PE supplement). Healthy aged rats fed ad libitum with a standard diet were studied in parallel. Whereas no changes occurred in the jejunal segment, an adaptive villus hyperplasia was observed in the proximal ileum of rats receiving PE without an increase in the brush border hydrolase activities. Our results indicate that oral PE supplementation exerts a trophic effect on the ileal mucosa of aged rats in response to nutritional stress.