100 NEUTRON EFFECTS ON ANIMALS 



the first day, a still further increase in 7 globulin beyond that of the 56th 

 day, and a small decrease in albumin. 



Effect of Neutron Irradiation on Plasma and Serum Composition. In 

 view of the close resemblance, with respect to plasma composition, among 

 rabbits A, C, and D on the first day of observation, the constancy of plasma 

 composition for rabbit D throughout the period of observation appeared 

 to warrant the conclusion that probably no significant change occurred in 

 the plasma of rabbits A and C during the twelve days prior to irradiation, 

 and that any changes observed later were largely the result of the irradiation 

 and its secondary effects. 



Rabbit A died less than 24 hours after irradiation. The plasma and 

 serum obtained just prior to death were opaque with suspended material 

 of low density. To remove this, the plasma and serum were frozen in small 

 centrifuge tubes, then allowed to melt; a protein-impoverished layer was 

 thus formed near the surface of each. When the samples were then sub- 

 jected to prolonged centrifuging in a multispeed attachment with dry ice 

 cooling, the suspended matter rose into the protein-impoverished layer, 

 and was removed. The plasma and serum, now much clearer, but also 

 more concentrated, were then diluted and dialyzed as usual for electro- 

 phoresis. The plasma protein concentrations computed from the resulting 

 electrophoresis diagrams were corrected for the concentrating effect of this 

 procedure on the basis of the nitrogen analysis of the plasma before centrif- 



An X 10^ 

 ugation (see Table II), and of the ratio, ^ — = 19.6, for the plasma 



g.% 

 from the same animal on the first day of observation. The serum protein 



concentrations were arbitrarily corrected to the same total protein content 



as the plasma. The only change shown by the electrophoresis diagrams 



as a result of the irradiation was a possible slight increase in a globulin. 



Eabbit C, which was sacrificed twelve days after irradiation, showed 

 a diminution in total plasma protein concentration of about 10 per cent 

 (Table V), resulting almost entirely from the decreased concentrations of 

 j8 globulin and fibrinogen. There was little change, therefore, in the plasma 

 protein composition of either rabbit following irradiation. 



In a more extended study of the plasma proteins of irradiated rabbits 

 (9), a diminished 7 globulin content was found to be a characteristic re- 

 sponse. It appears that rabbit A was examined too soon after irradiation 

 for this response to have occurred; and for rabbit C the 12-day interval 

 between irradiation and examination was sufficiently long for a return 

 to the initial value (cf. Table IV of Chapter 14). 



Effect of Sonic Treatment on Plasma. Samples of plasma from the final 

 bleedings of rabbits B, C, D, and E were subjected to sonic treatment for 

 the same length of time as the corresponding bone marrows. The results, 



