REGIONAL DISTRIBUTION OF TRANSFORMING GROWTH-FACTOR-ALPHA AND EPIDERMAL GROWTH-FACTOR IN NORMAL AND PORTAL HYPERTENSIVE GASTRIC-MUCOSA IN HUMANS

This study was designed to evaluate the concentration and the regional distribution of TGF-alpha and EGF in normal and portal hypertensive h uman gastric mucosa. To this end we measured by RIA the gastric and du odenal concentration of TGF-alpha-or and EGF in subjects with chronic hepatitis, who had normal gastric endoscopic appearance, and in patien ts with liver cirrhosis with and without congestive gastropathy. Our r esults show that TGF-alpha concentration is significantly higher than EGF concentration in both the stomach and duodenum. No significant reg ional differences in the distribution of the two peptides were found. Moreover, the gastroduodenal tissue levels of TGF-alpha were comparabl e in subjects with and without hypertensive gastropathy. EGF gastric c oncentration was not altered in patients with congestive gastropathy. However, EGF duodenal tissue levels were significantly lower in patien ts with liver cirrhosis than in noncirrhotic subjects. We speculate th at the higher level of TGF-alpha in the gastroduodenal mucosa may supp ort the hypothesis that TGF-alpha and not EGF is the major physiologic al ligand for TGF-alpha/EGF receptor in the intact gut. Furthermore, t he lower duodenal concentration of EGF in cirrhotics might partially e xplain the increased susceptibility of cirrhotic patients to duodenal ulcer.