PHARMACOLOGY AND TOXICOLOGY OF SUPKARENALS 245 



ing the suprarenal medulla with the kidney (Fig. 4). When injected by 

 way of the rete, these regions appear where the vessels enter as cones with 

 their bases in the renal capsule, their apices extending into the renal me- 

 dulla in many instances. Cow was led to this discovery by the observation 

 that when the kidney was perfused by fluid entering through the thoracic 

 aorta, all visible arteries except the renals being tied, the amount of urine 

 progressively decreased as did also the rate of the perfusion flow. On the 

 other hand perfusion directly 

 through the renal artery invari- 

 ably caused a progressive rise 

 in the amount of urine, usually 

 although not always accom- 

 panied by an increase in the 

 perfusion flow. The different 

 results in the two methods of 

 perfusion could be accounted for 

 by passage of a portion of the 

 perfusion fluid through minute 

 vessels, which had been over- 

 looked, leading to the suprarenal 

 from whence epinephrin was 

 washed and carried to the kid- 

 ney. 



Whether such vascular con- 

 nection between the suprarenal 

 and kidney exists in man has 

 not been shown so far as we 

 know. The work of Marshall 

 and Kolls indicates its absence 

 in the dog. However, suprarenal 



products might affect the kidney by way of. the general circulation as 

 shown by Addis and his coworkers. 



Instead of a reduction of the excretory power of the kidney as indicated 

 by Cow's perfusion experiments (urine volume determined) Addis, Bav- 

 nett and Shevky found that suitable doses of epinephrin injected sub- 

 cutaneously produce an increase in the urea secretion (rabbit) when meas- 

 ured over hourly periods. There is a certain amount of epinephrin which 

 produces the greatest increase in function, smaller amounts having less 

 and less effect until there is no change from the normal. With larger 

 amounts the augmenting effect on secretion also becomes less until, with 

 relatively large doses, a decrease in function is found. 



Intravenous doses of epinephrin, at least in the amounts which cause 

 a visible change of the volume of urine, inhibit the urine flow for a brief 

 interval as shown by Gunning. Although he did not observe diuresis fol- 



Fig. 4. Veins to the suprarenal of the cat. 

 The rete of vessels connecting the suprarenal 

 with the kidney, after the diagram of Cow. 

 ad., suprarenal; a., common lumbo-suprarenal 

 vein; I., lumbar vein joining the suprarenal 

 vein; v. c., vena cava. 



