Helen R. Jervis

EFFECT OF EXPOSURE CONDITIONS ON THE PRODUCTION OF RADIATION LESIONS IN RAT SMALL INTESTINE.

Conclusions The 2000 R X-irradiation of small gut of the rat in general produces a shortening of the viscus which is time dependent. This dose, when delivered either to the whole-body or to the abdomen only, produces in the small gut of the rat the uniform classic lesion of the acute intestinal radiation syndrome, but without generalized denudation. The characteristic, foamy, epithelial cells that line most of the luminal surface after the third day are packed with large lipid droplets. The same dose, when applied to the exteriorized gut produces patchy lesions with areas similar to the above, interspersed with apparently intact areas usually concentrated in the upper small intestine. There are indications that the intact areas might have escaped the full effect of the dose delivered due to some interference with their blood supply resulting from the process of exteriorization.

Absorption of Iron Following X-Irradiation of the Exteriorized Small Intestine

Summary The intestinal absorption of radioiron was determined following X-irradiation of the exteriorized small intestine in the rat. The morphologic lesion resulting was discontinuous, with areas of intestinal radiation injury alternating with areas which were essentially intact or hypertrophic. The results indicate that there was an increase in radioiron absorption following irradiation and suggest that this increase was due to augmented absorption in those areas of the small intestine which did not develop the morphologic characteristics of severe radiation injury. Possible mechanisms are discussed.