AMMONIA. 767 



gastric juice and the ammonia elimination. Thus SCHITTENHELM found 

 that with a rise in the hydrochloric acid content the percentage of ammonia 

 in the urine was raised and also the reverse. A. LOEB and GAMMELTOFT l 

 have also observed a fall in the ammonia elimination a few hours after a 

 meal, although no satisfactory explanation of this behavior has been given. 

 That ammonia plays the role of a neutralization medium for the acids 

 produced in the body or introduced therein has been shown by various 

 observations. 



In man and certain animals the elimination of ammonia is increased 

 by the introduction of mineral acids; and, as shown by JoLiN, 2 organic 

 acids, such as benzoic acid, which are not destroyed in the body act in a 

 similar manner. The ammonia set free in the protein destruction is in 

 part used in the neutralization of the acids introduced, and in this way 

 a destructive removal of fixed alkalies is prevented. 



Acids formed in the destruction of proteins in the body act on the 

 elimination of ammonia like those introduced from without. For this 

 reason the quantity of ammonia in human urine is increased under such 

 conditions and in such diseases where an increased formation of acid 

 takes place, because of an increased metabolism of proteins. This is the 

 case with a lack of oxygen in fevers and diabetes. In the last-mentioned 

 disease, organic acids /3-oxybutyric acid and acetoacetic acid are pro- 

 duced, which pass into the urine combined with ammonia. 3 



The liver forms urea from the ammonia supplied to it by the blood 

 and it would therefore be expected that in certain diseases of the liver 

 or with insufficient liver function that a diminished urea formation and an 

 increased ammonia elimination should take place. This condition has 

 already been mentioned above (page 685), and as there remarked we 

 must consider whether the abnormal production of acid with increased 

 elimination of neutralization ammonia is primary or whether it is a 

 diminished synthetic activity of the liver. 



In close relation to what has been said stands the question whether all 

 of the ammonia occurring in the urine under normal conditions is to be 

 considered as neutralization ammonia. If this were so then probably 

 by introducing large amounts of alkali it would be possible to cause the 

 disappearance of ammonia from the urine. In STADELMANN and BECK- 



1 Bouchez, Journ. de Physiol. et de Path., 14; Schittenhelm, Deutsch. Archiv. f. 

 klin. Med., 77; Adam Loeb, Zeitschr. f. klin. Med., 56, and Zeitschr. f. Biol., 55; Gam- 

 meltoft, Zeitschr. f. physiol. Chem., 75. 



2 Jolin, Skand. Arch. f. Physiol., 1. In regard to the behavior of ammonium salts 

 in the animal body, see Rumpf and Kleine, Zeitschr. f. Biologic, 84; Kowalewski and 

 Markewicz, Bioch. Zeitschr., 4, and the works cited on pages 682, 683. 



3 On the elimination of ammonia in disease, see the works of Rumpf, Vir chow's 

 Arch., 143; Hallervorden, ibid. . 



