Measurement of Canine Intestinal Capillary Blood Flow in the Terminal Phase of the Gastrointestinal Radiation Syndrome.

摘要

The objective of the study was to test a method of measuring the distribution of intestinal capillary blood flow. Adult male beagles were divided into two groups,one of which was sham irradiated while the other was subjected to 1500rads of whole-body pulsed gamma-neutron radiation. Seventy-two hours postirradiation,radioactive-tagged microspheres were injected directly into the left ventricle of the heart. The results showed that the intestinal capillary blood flow (in percent of cardiac output) of the irradiated dogs was higher than that of the nonirradiated dogs. Although the weight of the mucosal layer of the small intestine decreased significantly postirradiation,its relative capillary blood flow remained at the preirradiated level,indicating increased capillary blood flow per unit weight of mucosa. The method was successfully applied to the measurement of mucosal flow as a function of cardiac output and can be applied to the study of the pathophysiology of a variety of stresses including irradiation. (Modified author abstract)