132 .loniXAL OF TlIK AIlTC'IIKI.L SoCIKTY ID 



ec. 



parentl.v not the sole fiictor wliieli determines the degree of 

 diuresis. In experiment 6, for instance, a vasodilation in- 

 creasinu' the kidncv vohnne -{-87 mm. does not increase the 

 llow of in'iiic. The flows of urine was one drop per minute 

 both l)efore and after the injection of caffein. In experi- 

 ment 2, however, with a rise in kidney volume of only 4"^^ 

 mm. the output of urine per minute was doubled; the urine 

 flow iuci'easini>' from 9-18 drops per minute. 



When adrenalin was employed in the animals of this 

 group it invariably induced a vasoconstriction of the renal 

 vessels and a decrease in kidney volume (tracing G). 



The degree of vasoconstriction varied from a minimum 

 response of — 18 mm. to a maximum response of — 60 mm. 

 The effect of the vasoconstriction was either to reduce the 

 flow of urine or to cause a temporary stoppage of urine flow. 

 The most marked effect from adrenalin in reducing the flow 

 of urine occurred in the experiments in which the maximum 

 constrictor effect from adrenalin was obtained (experiment 

 2, table 3). 



In this experiment a fall in kidney volume of ^60 mm, 

 was obtained from adrenalin, and the flow of urine was re- 

 duced from 18 drops per minute to 6 drops per minute. 



Group II. Anuric Animals 



GreJiant's anestJietic. Seven full grown animals were used 

 in this group. All of the animals were diuretic on the day of 

 the experiment. 



Followign Grehant's anesthetic, in GO per cent strength 

 all of the animals of this group became anuric and remained 

 anuric throughout the experiments. 



The renal vessels were responsive to the dilator effect of 

 caftein (tracing 3). 



The degree of vasodilation varied between a mininuim re- 

 sponse of -|-17 mm. to a maxinuim response of -\-^S mm. In 

 none of the experiments was the vasodilation associated with 

 the establishment of a flow of urine (table 2). 



In this group adrenalin induced a vasoconstriction and 



