974 RADIATION BIOLOGY 



uric acid levels occurs in the lyrnph 4 hours after X irradiation and 

 coincides with the period of greatest lymphocyte destruction (Brown 

 et al., 1950). Part of the late rise in plasma nonprotein nitrogen in dogs 

 can be accounted for by the terminal anuria. Plasma urea nitrogen 

 follows closely the change in nonprotein nitrogen. There is little altera- 

 tion in nonprotein nitrogen with daily dosages of 10 to 50 r, although a 

 sharp fall may be noted terminally with the higher dosage (Prosser and 

 Moore, 1946). The reason for this difference in terminal behavior 

 between dogs irradiated acutely and chronically is not clear. After 

 neutron exposure (400 n in four divided doses) plasma NPN in the dog 

 falls on the third day and is decreased until death (Ross and Ely, 1947). 



Plasma glucose is increased in the guinea pig and rat (Kohn, 1950, 

 1951a; Lourau and Lartigue, 1950a). The change roughly parallels that 

 of nonprotein nitrogen, and it has been suggested that the gluconeogenesis 

 necessary to maintain hyperglycemia during the period of radiation 

 anorexia is partly responsible for the rise in NPN (Kohn, 1950). Plasma 

 glucose is also increased in the rabbit and dog after neutron or X irradia- 

 tion (Ross and Ely, 1947; Prosser, Painter, Lisco, et al., 1947). In the 

 X-irradiated dog, blood sugar is increased for several days prior to the 

 onset of fever and normal levels are found terminally. This is appar- 

 ently not the case with neutron irradiation where hyperglycemia is 

 progressive until death. Glucose concentration of lymph is unaltered 

 during the first few days after X irradiation (Brown et al., 1950). 



There is a variable pattern of change in the principal electrolytes of 

 plasma. Chloride rises in the rat and guinea pig after comparable dosage 

 (Kohn, 1950, 1951a). The increase occurs on the third day and normal 

 levels are evident by the second week. Blood cell chloride declines 

 roughly in proportion to the plasma increase; thus, the total chloride is 

 not altered appreciably. Plasma inorganic phosphorus rises slightly in 

 the rat and parallels the hyperglycemia and elevated NPN (Kohn, 1951a). 

 Serum sodium is also elevated in this species, while serum potassium may 

 rise slightly or remain within normal limits (Bowers and Scott, 1951a, b; 

 Bennett et al., 1949; Kohn, 1951a). Consistent changes in the plasma 

 levels of sodium, potassium, calcium, chloride, and phosphate have not 

 been observed in dogs following acute or chronic exposure to X rays 

 (Soberman et al., 1951; Prosser and Moore, 1946; Fink, 1946), and only 

 minimal effects have been seen following neutron irradiation (Ross and 

 Ely, 1947). There are few recent data relating to acid-base balance; 

 carbon dioxide combining power is said to be decreased in rats on the 

 fourth day after a total-body exposure to 600 r (Kohn, 1951a). 



Increased amounts of lipids have been detected in several mammalian 

 species following total-body irradiation. Turbidity of plasma, presum- 

 ably a result of the large increase in total lipid, has been observed in the 

 rabbit and is believed to presage early death in this species (Rosenthal, 



