604 



ADVENTURES IN RADIOISOTOPE RESEARCH 



in the deposited iron (in ferritin and haemosiderin of the bone marrow) , 

 for example, 10 hr after transfusion, could only be derived from the 

 erythrocytes degraded in this organ. Erythrocytes do not set free any 

 ^^Fe as long as they are intact. This could be proved by performing 

 experiments in which the labelled red corpuscles were first circulated 



Table 1. — Distribution of the »^Fe from the trans- 

 fused RED CORPUSCLES, WHICH WERE NOT HAEMOLYSED 

 IN THE ACCEPTOR RABBIT, BETWEEN THE FERRITIN PLUS 

 FERRGSIDERIN FRACTIONS OF THE ORGANS 



(3 hr experiment) 



500 



400 



300 



200 



100 



'^ Kontroll 

 • Tumor 



• • 



8 8 



° ° ° o ° 



10 



15 



20 



25 



Toge 



FIg. 6. Spleen weights of control and tumour-bearing mice. 

 Kontroll — control; Tumor — tumour; — Tage — days. 



for 2 days in a sister acceptor, in order to allow the escape of any possible 

 mobile ^^Fe, and then adding these corpuscles to a third rabbit. These 

 experiments yielded a result similar to that first discussed. The organ 

 in which most of the erythrocytes end their physiological life is the 

 bone marrow, with the liver occupying second place. One gm of spleen 

 contained more Fe^^ than 1 gm of any other organ. Since the weight 

 of the spleen is very small, especially in the rabbit, the whole spleen 

 contained much less ^^Fe than either the whole of the bone marrow or 

 the whole liver (cf. Table 1). 



