THE PHYSICAL INSTABILITY OF HUMAN RED 



BLOOD CELLS AND ITS POSSIBLE IMPORTANCE 



IN THEIR SENESCENCE* 



J. E. Lovelock 



National Institute for Medical Research, London 



According to Comfort (1954) in a review of the biological 

 aspects of senescence: "All theories of senescence at the pre- 

 sent time must be based on unwarrantable assumptions in the 

 absence of concrete answers to the essential questions of 

 fact". One assumption which seems generally acceptable 

 however is that senescence is in some way connected with 

 "wear and tear", or in physical terms with the natural tend- 

 ency for disorganization or entropy to increase with the passage 

 of time. 



The notion that senescence is due to wear and tear in a 

 mechanistic sense, namely, that living organisms wear out as 

 a result of their continued activity, is probably erroneous but 

 lies behind the widespread belief that the slowing or arrest 

 of metabolism at low temperatures would lead to suspended 

 viability. In recent years a considerable body of information 

 has accumulated on the effects of low temperatures on living 

 cells, and this resulted primarily from the important discovery 

 of Polge, Smith and Parkes (1949) that spermatozoa could be 

 protected against the otherwise fatal effects of freezing by the 

 addition of glycerol to their suspending medium. 



Since that time many types of living cell have been preserved 

 in the frozen state for periods greater than their normal life- 

 span. It is found, however, that living cells do not necessarily 

 survive for long periods when their temperature is lowered to a 

 level sufficient to reduce metabolism to a negligible value. 

 The progressive loss of red blood cells stored at —78° has been 

 reported by Mollison, Sloviter and Chaplin (1952), and at this 



* This paper was presented by Dr. A. S. Parkes on behalf of Dr. Lovelock. 

 —Ed. 



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