986 RADIATION BIOLOGY 



local rather than a systemic effect of the radiation. Peptic activity of 

 the gastric juice is diminished but not to the same extent as the acidity 

 (Ivy et al, 1924; Ely and Ross, 1947). This is of interest, since histo- 

 logical observations reveal that the chief cells of the gastric mucosa are 

 more sensitive than the parietal cells, which are more intimately con- 

 cerned with acid secretion (Friedman, 1942; Hueper and de Carvajal- 

 Forero, 1944). Radiation has been employed clinically to reduce gastric 

 secretion in patients with ulcers; the advisability of such therapy may be 

 questioned, however, since it may itself lead to perforation and hemor- 

 rhage (Friedman and Warren, 1942; Brick, 1947; Ricketts et al, 1948). 

 In view of the extensive injury to the gastrointestinal tract following 

 irradiation of the abdomen, it is reasonable to assume that absorption 

 will be impaired. While decreased intestinal absorption has been 

 observed by several investigators (Martin and Rogers, 1923; Buchwald, 

 1931; Barron et al, 1947), others (Mead et al, 1950) believe that there is 

 no basic disturbance. The problem is complicated by changes in 

 emptying time of the stomach and in intestinal motility. Inhibition of 

 glucose absorption and diminished phosphorylation of fructose have been 

 observed as early as 4 hours after X irradiation (Barron et al, 1947). 

 The absorption of cream is also said to be diminished (Martin and 

 Rogers, 1923). Although an increase in fecal fat has been observed in 

 human beings treated with X rays (Dodds and Webster, 1924), similar 

 increases may be seen in animals on a fat-free diet (Mead et al, 1950). 

 There is little interference, moreover, with absorption of fat in irradiated 

 mice (Mead et al, 1950) and of vitamin A in irradiated rats (Bennett, 

 Bennett, et al, 1950) during the first postexposure week. There are 

 also indications that total-body irradiation does not disturb protein 

 absorption (Bennett et al, 1951). Enteral administration of protein 

 hydrolysates is apparently as efficacious as parenteral administration in 

 lowering the sensitivity of irradiated protein-depleted rats (Jennings, 

 unpublished observations, 1950). Mead and his associates (1950; 

 Bennett et al, 1951) believe that the mechanisms of absorption are 

 not impaired by irradiation and that the changes that have been noted 

 can be attributed in many instances to concomitant effects on motility. 

 The available data are largely restricted to the early period after 

 irradiation; little is known about gastrointestinal function in the inter- 

 mediate and terminal periods following acute exposure. Even less can 

 be said about the nutritional status of the irradiated organism and its 

 potential contribution to the radiation syndrome. 



LIVER 



It is assumed from morphological studies that the liver is relatively 

 resistant to radiation (Seldin, 1904; Smyth and Whipple, 1924; Pohle and 



