EFFECT OF IRRADIATION ON HEMIN FORMATION 



627 



to a change in the sensitivity of the radioactive indicator. 'Phe increase 

 in the iron content of the plasma of the irradiated animals (Schuck/^®^ 

 LuDEWiG^"^) remains behind the increase of its ^^Fc content and corres- 

 pondingly the sensitivity of the radioactive indicator decreases. Thus we 

 can expect more ^^Fe to reach the liver in the exposed animals than in 



Table 1. — Effect Exposure to 500 — 1 400 r on the Incorpo- 

 ration OF s^Fe into the Cytochrome b of the Liver of 

 GriNEA-piGS. Each Figure is Obtained by Pooling 5 livers 



the controls. If this line of thought is correct we must expect the ratio 

 of the specific activity of the iron of exposed and control animals, which 

 for cytochrome b was found to be 1.3, to be about 1.3 for other liver 

 fractions as well (as far as their rate of formation is not influenced by 

 irradiation). As seen from Table 1 this is almost the case for microsome 

 ferritin, 1.32 being found for the corresponding ratio. 



Elmlinger et aZ.^^^^ found in normal humans about 55% of the iron 

 which passed the plasma to be utilized in red corpuscle formation. The 

 rest takes its way into the other organs. Should the last mentioned inflow 

 be unilateral, the iron content of these organs would increase already in 

 the course of 120 days with about 2 gm which is more than the total iron 

 depot of a man which amounts to about 1.6 g (Haskins^^^V We have 

 therefore to conclude that the flow of iron from the plasma into the depot 

 organs goes hand in hand with an outflow of an even larger amount of 

 iron from the depots into the plasma. 



40^ 



