218 



J. E. Lovelock 



dissolution of red cells during their storage at low tempera- 

 tures. The progress of the dissolution is described and the 

 structure and state of the cell membrane discussed in the light 

 of the experimental observations. The possible relevance of 

 these observations to the problem of senescence is also discussed. 



The dissolution of red cells in the temperature range 



0° to +40° 



The suspension of human red cells in 0-16M-NaCl is fol- 

 lowed by a loss of lipid components from the cell membrane 

 and to a lesser extent by haemolysis (Lovelock, 1954). The loss 

 of lipids is rapid at first, but after 3 minutes an equilibrium 

 level is reached, and the rate of loss falls to a low value. The 

 equilibrium concentration of lipids does not appear to repre- 

 sent a simple saturation of the medium with these substances, 



30r 



5 10 15 



NUMBER OF WASHINGS 



20 



Fig. 1. The removal of components from the red cell by repeated 

 washing. The cells were suspended in 16 M-NaCl for 10 min. at 

 37°, separated by centrifuging and resuspended in fresh 0-16 



M-NaCl. This was repeated 20 times. 

 + Lipoprotein ; □ Volume ; 3 Cholesterol ; 



X Phospholipid; O Haemoglobin. 



