The Concentration of Ammonia. 



125 



ciated with an impaired liver activity. That there is a marked 

 similarity of the symptoms of ammonia poisoning and meat intoxi- 

 cation after Eck fistula to those of complete thyroidectomy was 

 also pointed out and is further confirmed by the present work. 

 These experiments were carried out at the suggestion of Dr. 

 Carlson with the view of determining whether the ammonia con- 

 centration in the blood of animals in parathyroid tetany is suffi- 

 cient by itself to cause tetany, assuming that no tolerance to the 

 ammonia is developed. 



Slow injections of ammonium carbonate in solution were made 

 intravenously, the saphenous vein in dogs, and the jugular vein in 

 cats being used. Blood samples were drawn for analysis when 

 the symptoms became of the severity usually observed in para- 

 thyroid tetany or had returned to such after excessive injection. 

 Some differences in ammonia content are inevitable and are due to 

 the rapid diffusion of the ammonia into the tissues and the lymph, 

 to elimination by the kidneys and to conversion into urea by the 

 liver. The results obtained are as follows : 



Ammonia Content of the Blood in Mgr. per zoo c.c. 



Dog No. 1 2.8 Cat No. I 3.44 



" No. 2 2.1 " No. 2 3.64 



" No. 3 3.7 " No. 3 1.88 



" No. 4 1.75 " No. 4 2.40 



" No. S 2.4 " No. 5 2.34 



" No. 6 2.47 

 " No. 7 3.18 



Blood samples of six normal and three thyroidectomized dogs 

 in tetany were analyzed for comparison and found to average : 

 normal, 1.438, thyroidectomized 2.73 mgr. per 100 c.c. The 

 ratio for cats is: normal (average for five animals), 1.57, and 

 thyroidectomized (average for six animals), 2.53. 



The symptoms observed after ammonia injection are very 

 similar to those of complete thyroidectomy. There is a pre- 

 liminary phase of dyspnoea and salivation usually accompanied by 

 depression and more or less somnolence. Further injection 

 results in twitching of muscles, which may be suddenly followed 

 by opisthotonus and respiratory standstill (a condition observed in 

 three or four parathyroidectomized cats under observation last fall). 



