82 THE PHYSIOLOGY OF PROTEIN METABOLISM 



( 1 60) and Falta (122) on the prolonged excretion of nitrogen which 

 sometimes follows the administration of protein is also in support of 

 this storing of nitrogen. Abderhalden (4) has also produced a cer- 

 tain amount of evidence in its support. He found that a high intake 

 of protein before a fast was not necessarily followed by a big output of 

 nitrogen on the first day of the fast. He held, however, that the re- 

 tention of nitrogen did not take place in a protein form, and further, 

 that even in starvation there was an attempt by the animal to hold on 

 to this " free " nitrogen. Morawitz (288 A) has also given some con- 

 tributory evidence in his work on the formation of the blood proteins. 

 He found after thorough bleeding and replacement of the removed 

 blood by a suspension of blood corpuscles in Locke's solution rendered 

 viscid by gum, albumin and globulin did not re-form at the same rate. 

 The albumin gradually appeared in the first few hours after the bleed- 

 ing, but the globulin much later. He concluded that the initial supply 

 of albumin must have come from some store in the tissues. This re- 

 formation of blood proteins took place also during starvation, but in 

 this condition he stated that the re- formation of the globulin was if any- 

 thing more rapid than the albumin. 



Probably the only other condition in which this retention of protein 

 can be readily demonstrated (in addition to that caused by training or 

 work already referred to) is during growth and convalescence from a 

 wasting disease. Rubner (344) has dealt exhaustively with the pro- 

 blems of retention during growth, and there are a large number of 

 clinical papers bearing on the latter point, as for instance that of W. 

 Hale White and Spriggs (420 A) who showed that there was a daily 

 retention of over twelve grms. of nitrogen in a woman who increased 

 from 39-2 kilos (after inanition from worry) to 52-49 kilos in 55 days. 



Siven (374) in his experiments has given a very practical example 

 of the difficulty of getting protein stored in the body even when the 

 conditions for such retention might have been held to be particularly 

 favourable. After his feeding experiments with a low nitrogen diet 

 when he had lost almost I kilo of muscle 32-41 grms. N., he suddenly 

 increased the daily nitrogen to 1 3 grms., but found after fourteen days' 

 feeding a storage of only 14-49 grms. N., and of this 11-93 grms. were 

 retained during the first four days. He then raised the nitrogen intake 

 to 22-5 grms. daily and found only about 6*15 grms. nitrogen retained 

 in six days, most of it again being retained on the first day. In fact, on 

 three days out of the six there was actually a negative balance. For 

 the whole experiment there was thus only a retention of 20*64 grms. 

 nitrogen, or about two-thirds of what the organism had previously 



