[Histochemical study of the digestive organs of rats on board for the space flight of the satellite "Cosmos-690"].

The digestive organs of rats exposed to a combined effect of space flight factors and irradiation were examined. The surface and foveal epithelium of the stomach as well as mucocytes of the fundal glands showed a drastically reduced content of the neutral carbohydrate component. The foveal epithelium and mucocytes of fundal necks also exhibited a significant decrease of the sulfomucin content. The large and small intestines showed a lowered amount of goblet-cells and their secretion. Pancreatic acinar cells displayed different changes in the content of enzymic proteins having cation properties. The above histochemical changes did not return to normal 36 days after irradiation and 26--27 days after readaptation to the Earth environment.