Epidermal growth factor attenuates jejunal mucosal injury induced by oleic acid: role of mucus.

Epidermal growth factor (EGF) is present in biliary, pancreatic, and Brunner's gland secretions. The aim of the present study was to assess the effects of EGF on lipid-induced mucosal injury. The proximal jejunum of anesthetized rats was cannulated for perfusion of the lumen with emulsified oleic acid (40 mM oleic acid in 20 mM sodium taurocholate; pH 6.0). Mucosal epithelial integrity was monitored by measuring the blood-to-lumen clearance of 51Cr-labeled EDTA. Perfusion of the lumen with emulsified lipid increased EDTA clearance. Addition of EGF (0.5 ng/ml) to the lipid emulsion ameliorated the lipid-induced increase in EDTA clearance. Perfusion of the lumen with EGF alone stimulated mucus secretion from goblet cells. This effect of EGF was abolished by atropine. In addition, in atropinized animals there was 1) an exaggeration of the lipid-induced injury and 2) a loss of the protective effect of EGF. Our findings provide evidence supporting the hypothesis that EGF provides protection against lipid-induced mucosal injury, in part, by stimulating mucus production.