54 



PHYSIOLOGICAL KEGULATIONS 



The upshot is that water is not the same everywhere. The site 

 of the water and the rate of administration of it are distinguishable 

 factors. It may be inferred that the water content of the body is, 

 after one of these administrations, eventually adjusted to its initial 

 value ; meanwhile an excess is present, often for many hours. It 

 was found above (§13) that sudden additions of water lead to 

 faster elimination than gradual additions of equal amounts. Hence 

 any decrease in rate of passage or absorption is likely to decrease 

 the rate of recovery. By no known rule is the rate of output regu- 

 larly limited by a capacity of the kidneys ; time relations through- 

 out the body are factors. 

 +4 



-I 



O 



2 



hours 

 Fig. 34. Course of sensible water load in dogs subjected to four diverse regimes. 

 Single doses of water are given by stomach. Each point represents the mean of 6 or 7 

 tests on as many individuals, the same individuals being catheterized hourly in each set. 

 A and A', standard state; B, fed thyroid substances; C, deprived of food for 8 days but 

 allowed water ad libitum; D, deprived of food and water for 8 days. In D the sensible 

 water load does not represent the total water load, since water balance did not prevail at 

 zero time as it presumably did in the other tests. Data of Hatafuku ( '33a, '33b). 



c. Dogs subjected to various regimes are given water by 

 stomach. If deprived of food and water for 8 previous days (D, 

 fig. 34), they show no diuresis when 3% of Bq of water is given. 

 If previously given no food but allowed water ad libitum (C) they 

 have diuresis, yet only half of the water given is returned in urine 

 within 4 hours ; while all of it is returned by the same individuals 

 upon control days. It is quite arbitrary to define water balance 

 under such regimes. 



