150 G. K STEWART 



(the Meltfer-Ehrmann reaction with the frog's eye) is not an adequate 

 one for assaying epinephrin in blood. The conclusion that atropin does 

 not diminish the output of epinephrin has nevertheless been confirmed by 

 subsequent workers (Tscheboksaroff(a), Popielski(a) (1916), Stewart and 

 Rogoff(aO). Pilocarpin, according to Tscheboksaroff(a) is also without 

 effect, and Stewart and Rogoff (a?) came to the same negative conclusion, 

 on the basis of quantitative experiments by the rabbit intestine segment 

 method. Dale and Laidlaw, however, have stated that pilocarpin causes a 



Fig. 21. Intestine tracings. At 3, 5 and 7, Ringer's solution was replaced by 

 jugular blood and this at 4 by the fourth suprarenal specimen (collected one minute 

 after injection of nicotin) ; at 6 by the third suprarenal specimen (collected immediately 

 after injection of nicotin) ; at 8 by the eighth suprarenal specimen (collected seven- 

 teen minutes after nicotin injection). All the blood specimens were diluted with 3 

 volumes Ringer's solution. Since the third specimen was collected with a blood flow 

 quite as great as that for the fourth, the figure shows that the output for the third 

 must have been much greater than for the fourth. The detailed assay showed that 

 the output for the third specimen was more than 9 times as great as the initial output 

 before nicotin. The fourth specimen and also the fifth gave no inhibition with the 

 intestine segments, showing a marked depression of the output at this time. At the 

 time the eighth specimen was obtained the output had recovered to approximately the 

 initial value before the nicotin injection. (Reduced to two-thirds.) (After Stewart 

 and Rogoff, J. Pharm. < Eooper. Therap. ) 



marked increase in the rate of output, which in one experiment was as much 

 as 0.02 mgm. per minute for the cat, probably 30 times the average output 

 found by Stewart and Rogoff in cats and a greater output than they ever 

 observed even with strychnin or nicotin. The concentrations given by 

 Dale and Laidlaw are also extremely great, as much as 1 : 100,000 for 

 the blood. The serum would, therefore, have easily given a positive re- 

 action with the Folin colorimetric test. It is difficult to see how an in- 

 crease of this magnitude could have been missed in TscheboksarofPs ex- 

 periments made with the reliable blood-pressure method, or in Stewart 

 and Rogoff 's observations made with the both reliable and sensitive rabbit 

 intestine method. Dale and Laidlaw point out that the splanchnic was 

 cut in Tscheboksaroff's observations and not in their own. But it is 



