[Digestive system functioning during simulation of the microgravity effects on humans by immersion].

Functioning of the digestive system was investigated in 10 volunteers for 7-day dry immersion. The experimental conditions were found to raise secretory activities of the stomach, pancreas and liver, and to increase spectral indices of the GI electrical activity on the background of a higher than usual insular secretion and lowered gastrin secretion. The elevated GI electrical activities and changes in their ratios were a fallout of the increased gastric secretion and elevated intestines tone in fasting test-subjects and displayed a close similarity to the changes induced by caffeine stimulation, long-term bed rest or space flight.