THE INTERNAL SECRETION OF THE KIDNEY 445 



removal of the other sound kidney. The daily excretion of urine 

 was considerably increased, and amounted to two, three, or even 

 five times the normal, v. Haberer also observed polyuria after 

 reduction of the renal parenchyma. The daily excretion of 

 nitrogen also increased, though the diet was unaltered. This 

 negative nitrogen-balance disappeared when the amount of food 

 given was very much augmented. The animals showed con- 

 spicuous thirst and considerable appetite, and by increasing the 

 amount of the food until the nitrogen was two to two-and-a-half 

 times the former quantity, it was found possible to maintain the 

 nitrogen balance. Reduction in the amount of the diet was 

 followed by a progressive decrease in the excretion of nitrogen 

 until a nitrogen deficit was again observed. The condition of 

 animals in which the renal parenchyma had been reduced in this 

 manner underwent no other change. 



According to Bradford, the nitrogenous extractive substances 

 of the blood and tissues, and especially of the muscles, are con- 

 siderably increased in such animals ; he believes that there is rapid 

 decomposition of the tissues, particularly of the muscles. It is 

 expedient that mention of these metabolic changes should be 

 made here, though it is not possible at present to determine 

 whether they arise from suppression of the internal secretion of 

 the kidney or not. 



