THE PAEATHYEOID GLANDS 543 



ent in the blood of dogs and cats suffering from parathyroid tetany and 

 of normal animals, and found that "the concentration of ammonia in the 

 blood of cats and dogs in ammonia tetany is practically equal to that 

 in parathyroid tetany." Her findings thus give support to the view that 

 the increased ammonia in the blood of parathyroidectomized animals is 

 directly responsible for the tetany and the depression symptoms. 



Carlson and Jacobson, continuing these studies, found, by using the 

 more delicate method of Nessler in estimating the blood ammonia (Jacob- 

 son had employed Folin's method in her previous work), that the am- 

 monia content of the blood of dogs suffering from parathyroid tetany is 

 not appreciably greater than that of normal dogs; and that the intra- 

 venous injection of calcium salts, in quantities sufficient to suppress com- 

 pletely the spasmodic symptoms in these animals, does not reduce the 

 concentration of ammonia in the blood. They also noted the fact that 

 calcium salts have a much slighter effect on ammonium tetany than on 

 parathyroid tetany. Other points of distinction are mentioned by them; 

 e.g., dogs suffering from ammonia tetany show a much greater hyperex- 

 citability to auditory stimuli than is found in parathyroid tetany; and 

 again, while transverse section of the spinal cord in the upper thoracic 

 region of an animal showing extreme parathyroid tetany will abolish 

 muscular disturbances below the lesion, in pronounced ammonia tetany 

 it will not do so ; the whole body is still involved. They confirm Berkeley 

 and Beebe's statement that calcium and strontium are equally efficient 

 in suppressing the symptoms of parathyroid tetany. From these and 

 other results which they obtained they conclude that ammonia is not the 

 exciting agent in parathyroid tetany. With the exception of parathyroid 

 transplantation, all measures used in the treatment of parathyroid tetany 

 are only palliative, not curative, and act by temporarily diminishing the 

 excitability of the nervous system. 



Greenwald (a) (1911) found that the excretion of nitrogen was in- 

 creased only after the onset of tetany, when the muscular action was in- 

 creased; the proportion of the total nitrogen excreted in the form of 

 ammonia was very little, if at all, increased; the concentration of am- 

 monia in the blood during tetany was not higher than in normal animals. 

 The creatin.of the urine was very much increased, while creatinin excre- 

 tion was only slightly so. There was also an increase of sulphur excreted ; 

 and phosphorus was at first retained, but when the symptoms appeared, it 

 was excreted in excess. 



Albertoni also failed to find any increase of ammonia in the blood 

 during tetany. 



Cooke (c) (1911), on the other hand, reports an increase in the nitrogen 

 and ammonia in parathyroidectomy. In some animals lactic acid was 

 found in the urine. 



Gertrude Bostock, in Paton's laboratory, found that the muscular 



