CHRONIC TREATMENT WITH EPIDERMAL GROWTH-FACTOR CAUSES ESOPHAGEAL EPITHELIAL HYPERPLASIA IN PIGS AND RATS

Epidermal growth factor (EGF) is an important factor for maintaining t he esophageal functional integrity. Goettingen minipigs were treated w ith either placebo or subcutaneous EGF (30 mu g/kg/day) for four weeks . Wistar rats were treated with either placebo or subcutaneous EGF (15 0 mu g/kg/day) for four weeks. At sacrifice, esophageal samples were o btained for histology, immunochemistry, and lectin characterization. I n pigs, the thickness of the esophageal epithelium was almost doubled in the EGF-treated animals. Characterization with lectins revealed a n ormal pattern of differentiation. Subcutaneously administered EGF was visualized on cells located basally in the esophageal epithelium. In r ats, EGF-treatment increased the esophageal volume of the epithelium, the lamina propria of the mucosa, and the submucosa. In conclusion, sy stemic EGF challenge induces growth of the esophageal epithelium with an unaltered pattern of differentiation. This supports previous studie s demonstrating a beneficial effects of systemic EGF-treatment on scle rotherapy-induced esophageal damage.