METABOLISM OF THE NUCLEIC ACIDS 



401 



TABLE III 



The Incorporation of P'^ into the PNA of Various Tissues in 



Different Physiological and Pathological states Calculated 



Relative to the Normal Tissue in Each Group as 10 



° Cytoplasmic PNA as diatinct from total PNA . 



The results shown in Table III illustrate the effects of such factors on the 

 incorporation of isotopic phosphorus into PXA. It will be seen that in 

 liver regenerating after partial hepatectomy, the activity of the PNA is 

 three to four times that in resting liver.' ^--^^ Similarly, in fetal rabbit 

 liver the activity of the PNA is increased about twofold compared with the 

 normal, while a somewhat smaller increase is recorded with weanling rat 

 liver.' The incorporation of P'^ into the PNA of pregnancy-stimulated 



