658 



ADVENTURES IN RADIOISOTOPE RESEARCH 



RESULTS 



It has been shown repeatedly (Hennessy and Huff 1950, Huff, 

 Bethard, Garcia, Roberts, Jacobsen and Lawrence, 1950; 

 Belcher, Gilbert and Lamerton, 1954 ; Bonnichsen and Hevesy! 

 1955 {aj that about one day or later after exposure of the animal to 



15- 



200- 



150 



100- 



50- 



o 



D. 







10- 



o 



Dl 



n n 



Fig. 4. Ratio of ^^Fe up- 

 take by embryonal and 

 maternal liver of equal 

 weight. 



5- 



11 



-' 



^ 



Fig. 5. Ratio of the spe- 

 cific activities of embry- 

 onal and maternal circu- 

 lating hemoglobin. 



radiation the incorporation of ^^Fe into hemoglobin being strongly de- 

 pressed, more ^^Fe makes its way into the liver and other non-hemo- 

 poietic organs than in non-exposed controls. To the same reason is due 

 at least partly, the enhanced passage of the mother-injected ^^Fe into 

 the embryo of exposed rabbits, as seen in Fig. 1. A comparison of the 

 59Fe uptake by the liver of the mother and the embryo in control and 

 exposed rabbits is made difficult by the varying number of embryos 

 and thus of the embryonal livers and their weight in the different ex- 

 periments. The conspicuous concentration of ^^Fe in the embryonal liver 

 is however clearly demonstrated by Fig. 2. This in spite of the much 

 lesser weight of the embryonal liver (2, 5, 2, 1.4, 1.5, 2.0, 2.0and3.9gm) 

 than that of the maternal liver (86, 138, 128, 170, 95 and 100 gm). The 

 uptake of ^sFe by the maternal and foetal liver and their iron content 



