D. C. TOSTESON 



139 



that the electrical potential difference across the cell membrane is still defined 

 by the chloride ratio, even in the presence of butanol. This assumption is 

 justified by the observation that chloride flux (as measured with CF*) was not 

 appreciably slowed by butanol. Thus, the chloride flux remains several orders 

 of magnitude faster than the accelerated cation fluxes produced by butanol. 



Variation of flux tvitli concentration. Figure 2 shows the relation of K influx 

 to K concentration in the medium in cells exposed to 0.3 m/1. butanol. The 

 linear relation conforms to that predicted for diffusion in a system where the 

 electrical potential is independent of the K concentration. That this condition 

 still obtains in the butanol cell is confirmed by the above noted observation 

 that chloride flux remains much higher than K flux even in the butanol cell. 



HUMAN SICKLE CELL 

 ANEMIA CELLS - 37°C 



Fig. 2 (left). K influx into normal human red cells exposed to 0.3 m/1. n-butanol is plotted 

 as a function of K concentration in the medium ([K]m). 



Fig. 3 {rigid). K influx into the red cells of a patient with sickle cell anemia incubated 

 in O2 (disk shape) and N2 (sickle shape) is plotted as a function of K concentration in the 

 medium ([K]m). 



The value of D'k derived from the slope of this curve is 3.06 which agrees 

 fairly well with the value 2.65 obtained from the flux ratio analysis. 



Competition between K and Cs. In the presence of 0.3 m/1. n-butanol, there is 

 no competition between K and Cs for entrance into the human red cell. These 

 measurements are consistent with the conclusion that K transport in human 

 red cells exposed to 0.3 m/1. n-butanol is almost entirely by the process of 

 diffusion. 



Red Cells of Patients With Sickle Cell Anemia. Cation transport in sickle 

 cell anemia (S-S) red cells has recently been characterized in detail (106, 107, 

 109, no, 112). When incubated in oxygen, S-S red cells remain in the disk 

 shape and transport cations in essentially the same manner as do normal red 

 cells. Incubation in nitrogen produces transformation from disk to sickle and 

 marked changes in cation transport. For comoarison with normal and butanol- 



