ISOTOPIC INDICATORS IN HAEMATOLOGY 



649 



In contrast to the globulin iron, the non-physiological ly bound iron 

 has been shown by electrophoretic studies to pass into the intercellular 

 space essentially free from transferrin, as shown in Fig. 9; this diagram 

 shows the distribution of non-physiologically bound iron introduced into 

 the plasma, in the intercellular space and the cellular space of a normal 

 rabbit. 



The problems mentioned in the introduction can be solved in other, 

 though more tedious ways, e.g. by applying isotopic indicators, but a 

 determination of the iron turnover cannot be considerate without the 



N 

 E 

 E 



Normal-Koninchen 

 -pT-7 



Introcelluldres Fe 

 1-r 1" 



20 40 60 80 100 120 140 160 180 



Fig. 9. Distribution of non-physiologicaly bound iron(lnigni) added 

 to the plasma among the plasma, the intracellular space and the 

 cellular space of a normal rabbit. 

 Normal- Kaninchen = normal rabbit. 

 Intracellulares Fe = intracellular iron. 

 Lymphe Fe = lymph iron. 

 Plasma Fe = plasmairon. 

 1 mgm citrate ^^Fe added as citrate. 



use of radioactive tracers. Use of these indicators provides a possibility 

 of splitting up into components the dynamic equilibrium whose resultant 

 is the plasma iron level. The result of splitting up this equilibrium directs 

 our attention, with particular emphasis, to the importance of the de- 

 ficient flow of iron from the storage organs into the plasma in infectious 

 diseases and to some other pathological cases. In order to attain a per- 

 manent increase in the plasma iron level in such diseases it would be 

 necessary to increase the deficient flow into the plasma. 



That the lymph flow' plays a part in maintaining a normal plasma 

 iron level is shown by the observation of Ehrenstein, viz. that the 

 plasma iron level in a rabbit falls on the average from 191 to 146 //gm % 

 4 hr after removal of the ductus thoracicus and the truncus jugularis 

 sinister, whereas the level remains constant in control rabbits which 

 have been subjected to operation without removing the ductus thoracicus. 



