18 ANALYSIS OF DISTURBANCES OF METABOLISM 



to this increase by an increased excretion of vapor. In the investigations in 

 forced feeding, the fat accumulation, which can only be controlled by an 

 accurate estimation of the carbon balance, may also be less than authors have 

 assumed, judging by the caloric excess in the food. 



In such a profuse N-retention, the supposition that the accumulation of 

 nitrogen-containing end products of albumin metabolism may play a role 

 appears to be quite umvarranted for the reason that there are no sufficient 

 proofs that N-containing products of intermediary albumin metabolism re- 

 main as such in large quantities in the body of the healthy. The view is 

 much more likely that the N" is retained as albumin, and that this albumin 

 (as a native molecule, however, and without a corresponding participation of 

 water) enters the cell. As evidence of this Liithje points to the observation 

 that in certain snails albumin is found included in the cells in a crystalliae 

 form. 



It seems to me, however, that there is one phenomenon — which appears, so 

 far as I am aware, in all investigations regarding albumin accumulation if the 

 analyses in question are carried out — and which goes to show that the albu- 

 min accumulated in the protoplasm of the cells increases and rejuvenates it 

 while assimilating itself with the general cell albumin. I refer to the simul- 

 taneous retention of phosphorus when IST is retained, and its increased excre- 

 tion (as P2O5) during albumin decrease. This is shown in the investigations 

 of Kayser, and of Jacob and Bergell. It may be recognized also in Liithje's 

 metabolism figures, and only lately Kaufmann has called attention to the 

 decided phosphorus retention which he observed during a:lbumin accumulation 

 in feeding with 'egg albumin. The fact that any phosphorus containing albu- 

 min body especially favors albumin accumulation (as was shown by Eohmann 

 and his pupils, and also by Zuntz and Caspar!) favors this view. 



Quite an analogous N-retention (which probably no one will doubt means 

 an albumin accumulation) Eost ^ has observed in his metabolism control 

 experiments in growing animals. 



The amounts of nitrogen of the food which were not excreted in the urine 

 and feces of three young dogs were decidedly greater than could be accounted 

 for by the increase of body-weight, if the ]!^-accumulation were reckoned in 

 the formation of muscle albumin. Therefore, as in the investigations of 

 Liithje, either a loss of water occurred or the retained nitrogen was utilized 

 to build up a cell protoplasm with higher nitrogen contents than are found in 

 muscular substance. 



When it became necessary, in forced feeding experiments in animals with 

 meat free of fat, to promulgate a formula for the N-accumulation (Pfliiger, 

 Cremer) certain difficulties naturally arose. The amount of carbon retained 

 in the organs was greater in comparison with the nitrogen than would corre- 

 spond to the composition of albumin. 



If, with Pfliiger, we reject the possibility of a fat formation from albu- 

 min, although accepted by Volt's adherents, we must be content with assum- 



1 Rost, " Zur Kenntniss des Stoffwechsels wachsender Hunde." Veroffentlichungen 

 des kaiserl. Gesundheitsamtes, Bd. xviii, p. 206. 



