RADIATION DEATH IN MAMMALS 



In the case of the excretion of 1 7-ketosteroids the dose of 1,000 r has no effect. 

 Decrease of excretion starts at 1 ,200 r and takes place one day after irradia- 

 tion. The excretion of corticoids decreases at l,000r, beginning immedi- 

 ately after irradiation. The results of these tests are illustrated in Figure 6. 



Blood — Some changes in the blood after irradiation with large doses were 

 examined. For clinical purposes after irradiation the changes in the 'pro- 

 thrombin-time ' was studied in detail. These examinations carried out with 

 RoMER and Beller', showed a clear effect on the blood of m vitro irradiation 

 {see Figure 7). 



Investigations of metabolism — The metabolism of tissues irradiated in vitro 

 was measured by the method of Warburg^"- ^^ These investigations are still 



700 



% 



90 

 80 

 70 

 60 



50 



w- 



30- 

 20- 

 10- 



Figure 7. 



Decrease of ''prothrombin time ' after irradiation 

 of blood in vitro 



^0, 



r\ 



200 V-00 600 800 WOO 

 Doses kr 



J I I I I 



200 900 600 800 10^ 

 Doses kr 



Figure 8. Tissue respiration after irradiation in vitro of 

 {A) liver and {B) spleen of white mice 



¥00 eoo 



Doses 



in progress. Figure 8 shows two examples of the results obtained, i.e. respira- 

 tion of liver and spleen tissue slides after irradiation with high doses. 

 Especially the 'residual' respiration which is preserved after doses of 

 1,000,000 r had been applied, should be noted. 



The curves are analogous to those curves obtained earlier by Rajewsky 

 and Inouye^ by tissue irradiation with alpha-particles. 



FRACTIONATION OF DOSE 



To clarify the 3-5-day effect we investigated the time intensity factor in 

 this range. As already mentioned, change of irradiation time from 2-5 

 seconds to 10 hours gave no changes of the 3-5-day effect. We therefore 

 studied, in co-operation with Aurand^, the effect of dose fractionation. 

 I shall illustrate our results with only one example. In Figure 9 the curves 

 for the dose effect are represented for a single and for fractionated irradiation, 



90 



