RATE OF PENETRATION OF IONS INTO ERYTJIROCYTES 511 



Mr. Zerahn has investigated in oui' laboratory tlie rate of peiu>t ra- 

 tion of radiochloride into the corpuscles of the rabbit. The radiochloride 

 was prepared by bombarding carbontetrachloride with neutrons and by 

 extracting the radiochloride produced by the method of Szilard and 

 Chalmers. A small volume of a physiological sodium chloride solution 

 prepared from the chloride obtained by the process described above 

 was added to rabbit blood. Since the rate of penetration was expected 

 to be very rapid the experiments were carried out at 0° and the mixture 

 was shaken for 1 min only, previous to centrifuging. 



To the active corpuscles separated by centrifuging the corresponding 

 amount of non-active plasma was added, while the active plasma was 

 mixed with a corresponding amount of non-active corpuscles. Two 

 blood samples of the same weight were thus obtained, one of which 

 contained active corpuscles and the other active plasma. The blood 

 samples obtained by this procedure (about 100 mgm) were mixed with 

 100 mgm of CaO powder and were placed under the Geiger counter. 

 Since the ^^Cl used as an indicator has a half- lifetime of only 38 min, 

 this procedure has obvious advantages over the usual process in which 

 the blood samples are ashed or extracted. In these as in all other experi- 

 ments, the sharply centrifuged corpuscles were not washed, since washing 

 might lead to a substantial loss of labelled ions by the corpuscles. 



1 gm of corpuscle was found to contain about half as much ^^Cl 

 as 1 gm of plasma. Since the chloride content of 1 gm of corpuscle of 

 the rabbit makes out 0.53 times the chloride content of 1 gm of plasma 

 (Adlersberg and Glass, 1932), in the course of 1—3 min.W even at 0° 

 a very large portion of the corpuscle chloride was replaced by labelled 

 chloride originally present in the plasma. The rate of penetration of 

 chloride into the corpuscles of the rabbit is, thus, more than 100 times 

 larger than the rate of penetration of phosphate. 



PENETRATION OF LABELLED SODIUM INTO THE CORPUSCLES OF 



THE RABBIT 



In our first experiments (Hahn, Hevesy and Rebbe, 1939), labelled 

 sodium was administered to rabbits as sodium chloride by subcutaneous 

 injections. After the lapse of 1 day. we found 1 gm of sharply centri- 

 fuged, unwashed corpuscles to have a 24]SJa content amounting to 14 

 per cent of that of 1 gm of plasma. From these 14 per cent a few per cent 

 are due to the ^^Na content of the adhering plasma while the rest is due 

 to 24j^a penetrated into the corpuscles. The distribution ratio of ^^Na 



^^^ As the separation of thn rorpuseles from tho plasma Vjy centrifuging lasts 

 somo time, the duration of the experiment was somewhat more than 1 min. 



