SIGNIFICANCE OF THE SUPEAEENAL GLANDS 129 



greatly diminished or abolished. He was always able to demonstrate 

 epinephrin in the plasma of blood from the suprarenal veins of rabbits in 

 the concentration of 1 :1,000,000 to 1 :5.000.000. Since, as demonstrated by 

 Stewart and Eogoff(^) (1917), the epinephrin is practically confined to the 

 plasma the concentration in the blood would be about half as great (Fig. 

 1). Ehrmann's (a) (b) observations on rabbits, although constituting the 

 first attempt to measure the output of epinephrin, were seriously handi- 

 capped by the fact that he employed the frog's eye method for estimating 



Fig. 2. Arrangement for estimating concentration of epinephrin in suprarenal 

 vein blood, showing small cylinder in which the rabbit intestine (or uterus) segment 

 is suspended, with side tube for supplying oxygen. Vessels for the stock of intestine 

 (and uterus) and for warming the Ringer's solution and the blood samples are im- 

 mersed in the large constant temperature bath. A, holder of copper gauze for heading 

 blood specimens to temperature of the large bath; B, stand supporting recording ar- 

 rangement and small cylinder 8 (with side tube for oxygen) containing intestine (or 

 uterus) segment; C, cylinders containing Ringer's solution for washing and stock of 

 rabbit's intestine and uterus ; F, flasks through which oxygen is passed to the cylinders, 

 the oxygen being forced through the flasks from the bottles, B, shown in Fig. 3; R, tem- 

 perature regulator; T, thermometer. 



the epinephrin concentration in the suprarenal vein blood. It is not suit- 

 able for this purpose nor is it delicate enough. He obtained concentrations 

 of 1 :1,000,000 to 1 :10,000,000, while Waterman and Smit with the same 

 method obtained smaller concentrations. Borberg(a), on the other hand, 

 got much higher concentrations than Ehrmann (1:250,000 to 1:1,000,- 

 000) in 3 rabbits after piqure. In none of these observations was sufficient 

 attention paid to the measurement of the rate of blood flow from the supra- 

 renals. Without this the output cannot be calculated. 



Hoskins and McClure(&) in 5 dogs found the concentration in the su- 

 prarenal vein blood to correspond to from 1 :2,000,000 to 1 :8,000,000 of a 

 solution of "adrenalin hydrochlorid" (probably something like 1:3,000,- 

 000 to 1:10,000,000 of the base). They employed what is probably the 

 most accurate method for assaying epinephrin in bloood, the rabbit in- 



