Abstract
Capillary filtration in the experimentally irradiated small intestine of the cat was studied by measuring the capillary filtration coefficient (CFC). Segments of the small intestine were exposed to X rays of 15, 20, or 25 Gy and studied during the acute gastrointestinal radiation syndrome (4th day) and later (1 and 4 months). On the 4th day CFC had decreased to less than 60% of the original value. Increasing doses resulted in decreasing CFC. One month after irradiation CFC increased, but not to normal levels. After 4 months no further improvement was observed. With the higher doses a secondary decrease in CFC appeared, which might indicate a late effect of irradiation on capillary function.