Chapter 8 



THE EFFECT OF NEUTRON RADIATION ON SERUM ALIvALINE 



PHOSPHATASE ACTIVITY 



By FRANCIS E. REINHART 



The phosphomonoesterases, widely distributed as they are in the plant 

 and animal kingdoms, have been the subject of numerous investigations 

 concerned with the elucidation of their functions and physiological sig- 

 nificance. Much of this attention has been directed toward these enzymes 

 in respect to the changes they may undergo during a variety of pathological 

 conditions. Thus, liver damage and diseases involving the bone (rickets, 

 Paget 's disease, hyperparathyroidism, etc.) bring about an elevation in the 

 blood serum content of alkaline phosphatase. The activity of acid phos- 

 phatase in serum is likewise raised in prostatic carcinoma metastatic to the 

 skeleton. 



In view of the indications that neutron irradiation of living animals 

 may result in disturbances in the normal bone processes (1, 2), and of the 

 close relationship of serum alkaline phosphatase to the latter, an investi- 

 gation of this enzyme in the blood servnn of irradiated animals has been 

 initiated. Further interest in this problem arises from the work of Iwat- 

 sin-u and Nanjo (3) on rabbits subjected to X-rays. The leukopenia re- 

 sulting from this type of irradiation was found to be accompanied by a rise 

 in the activity of serum alkaline phosphatase. An increase in the activity 

 of this enzyme in serum has also been observed following X-ray treatment 

 in cases of chronic myeloid leukemia (4, 5). 



In the present study the serum enzyme activity in animals before and 

 after whole body irradiation with neutrons has been determined. These 

 observations, which are of a preliminary nature, were made on rats, rabbits, 

 and dogs, most of which served simultaneously for the purposes of other 

 investigations being carried out in this Laboratory. 



METHODS 



Serum. All l)lood samples were centrifuged approximately one hour 

 after removal from the animals. Phosphatase tests were performed on the 

 serum .samples within the next foui' hours. In the experiments with rats, 

 blood was obtained by decapitation of female albino animals averaging 

 about 200 g. in weight and maintained on a diet of "Fox Blox" and water. 

 They were used at the same time for studies concerning the changes in 

 spleen weight after irradiation {(')). 



6G 



