AZOTURIA. 
31 
is indirectly the cause of the paralysis, while the diseased liver, 
on the other hand, is the direct cause of the diseased kidney. 
The question may be asked, how is the liver the direct cause ? 
From a pathological point, any derangement of the liver in¬ 
creases the labor of the kidneys. The kidney becomes inactive 
from this source, and then refuses to perform its work. Func¬ 
tions are lost for the time being, with the result that the blood 
becomes contaminated with urea, as every ailment would be¬ 
come a poison if renal elimination was not the safeguard of the 
body. 
Urea.— As to why and how urea gets into the blood. It is 
known what the albuminous food contributes in digestion. 
Through a process of hydration by the action of ferments, are 
converted into peptones, which enter by absorption into the rad¬ 
icals of the portal vein, but an insignificant portion being ab¬ 
sorbed by means of the lacteals ; when once within the blood 
current, possibly in the process of absorption itself, the peptone 
must apparently be reconverted to the form of albumen, for the 
amount of peptone detected in the portal vein, even after an 
abundant albuminous diet, is too small to represent the amount 
of albuminous matter absorbed. We may, therefore, assert with¬ 
out fear of contradiction, that almost immediately upon enter¬ 
ing the blood-current the albuminous food constituents are con¬ 
verted mainly into serum-albumen. It has further been stated 
that urea represents the final product in the series of decomposi¬ 
tions which the albuminous bodies of the tissues undergo. The 
attempt to trace the changes, commencing with albumen, and ter¬ 
minating in the production of urea, is frustrated by the myste¬ 
ries of the process. It is known that with the withdrawal of all 
food the excretion of urea decreases.. It is further clear that 
urea is formed at the expense of the albuminous constituents of 
the tissues. That the excretion of urea may be increased by al¬ 
buminous food, and the amount of urea eliminated increases 
proportionately with the increase in albumen administered as 
food. Urea is not, however, a simple product of oxidation of 
albuminous bodies, but is a product of complicated decomposi- 
