GASTRIC-MUCOSAL ANTIOXIDANT ACTIVITY IN PATIENTS AT INCREASED RISK OFGASTRIC-CANCER

In 68 subjects the activities of Cu/Zn-superoxide dismutase (SOD), cat alase (CAT) and glutathione peroxidase (GSH-Px) were investigated in g astric mucosa. The patients were classified according to the histologi cal finding into following groups: 12 with normal finding (N), 16 with superficial gastritis (SG), 13 with mild atrophic gastritis (MAG), 19 with severe atrophic gastritis (SAG) and 8 with gastritis after parti al gastrectomy (PGG). The comparison of groups SG, MAG, SAC. and PGG w ith the group N revealed the following changes: in SG increased SOD an d GSH-Px, in MAG and SAG no significant changes, and in PGG increase i n SOD, CAT and GSH-Px were observed. It was supposed that increased en zymatic activities were caused by higher concentration of active oxyge n species produced by phagocyting leukocytes in inflammed gastric muco sa. Administration of vitamin E resulted in significant reduction of S OD and CAT activities, on the other hand GSH-Px activity significantly increased. The explanation or this effect of vitamin E requires furth er studies. A prolonged interaction of active oxygen species with chem ical carcinogens (N-nitroso- or diazonium compounds, PAH) can exhibit a significant promoting effect on the development of intestinal type o f gastric cancer from its precancerous conditions, above all after par tial gastrectomy.