METABOLISM OF THE NUCLEIC ACIDS 



397 



TABLE II 



The Relative Uptakes of P'^ by the DNA of Different Tissues in 



Different Physiological and Pathological States Expressed as 



Ratios Relative to the Normal Resting Tissues in Each 



Group as 10 



Species 



Tissue 



Time after Relative 



administration, hr. uptake 



Ref. 



Rat Resting liver 



Resting liver 

 Regenerating liver 

 Regenerating liver 

 Hepatoma 



Rabbit Resting liver 

 Maternal liver 

 Fetal liver 



Rat Resting liver 



Regenerating liver 

 Weanling liver 



Mouse Resting mammary gland 

 Pregnancy -stimulated 



mammary gland 

 Carcinomatous mammary 



gland 



Rat Resting liver 



Precancerous liver 

 Hepatoma 



Rat Resting liver 



Pregnant liver 



18 



127.5 



10.0 



67.0 

 136.8 



10.0 



24.5 



12 



13 



15 



14 



tumor in one tissue in rats, mice, and fowls or of a growing fetus in mice and 

 rabbits exerts a marked effect on the uptake of P^^ by the DNA of other 

 tissues. Thus in mice with mammary carcinomata and in pregnant mice 

 and rabbits the isotope uptake by the DNA of liver, spleen, and kidney is 

 very much higher than in the corresponding controls; this effect is not 

 observed in the DNA from the intestine of the host animals, nor does the 

 metabolic activity of the PNA of these tissues appear to be greatly dis 

 turbed by the presence of a tumor. These studies have been extended by 

 Payne et al.,^^ who, using formate-C^^ and glycine-2-C"', confirmed that 



13 A. H. Payne, L. S. Kelly, G. Beach, and H. B. Jones, Cancer Research 12, 426 

 (1952). 



