Glutathione transferase activity and reduce glutathione content in the cytosol of rat gastric mucosa cells under carcinogen N-methyl-N'-nitro-Nnitrosoguanidine treatment

Aim. To determine the activity of glutathione transferase (GT) and the content of reduced glutathione (GSH) in the cytosol of the gastric mucosa cells in experimental gastrocarcinogenesis. Methods. The activity of GT was determined spectrophotometrically, the content of GSH was measured spectrofluorimetrically. Gastrocarcinogenesis was initiated by 10-week replacement of drinking water by 0.01 % solution of carcinogen N-methyl-N'-nitro-N-nitrosoguanidine, at the same time the rats were given a diet containing 5 % NaCl. Results. It was established that at the end of the 4th and 6th weeks of consumption of carcino- gen and NaCl, the activity of GT increased by 26 and 94 %, whereas the content of GSH increased by 135 and 85 %, respectively. After 12 weeks there was a decrease in the activity of GT by 50 % and the maximum decrease in the GSH concentration by 69 %. At the end of the 18th and 24th weeks it was recorded the increase in the activity of GT by 44 and 47 % and the decrease in the GSH content by 55 and 52 %. Conclusions. The changes in the activity of GT and GSH-content are evidence of the violation of glutathione homeostasis, which may cause the delay as well as initiation of development of the pathology. The reduction of GSH is established at the early stages of tumors formation.