to animals" were, immediately after being killed, deprived of (lie 

 duodemum and the proximal part of the jejunum ; the mucous mem- 

 brane of these organs was rubbed np in the ordinary waj- and 

 mixed with 0.457o HCl, macerated for half an hour, then boiled, 

 neutralised with sodinm and tinall}" acidulated with some drops of 

 acetic acid. 



2. The laboratory animal. 



My first experiments were made on rabbits. I used this animal 

 because its amount of blood-sugar both in normal and abnormal 

 condition was pretty well known to me from earlier researches, in 

 which also the technique of the operation (ligature of the carotid), 

 presented hardl}^ any difliculty. According to the size of the animal 

 from 8 — 15 c.c. of secretin were given intravenously (per auricular 

 vein) ; at different intervals of time after the injection the amount 

 of sugar in the blood was estimated. 



3. Estimation of blood-sugar. 



The estimation was performed by cautious titration after Fehling. 

 Beforehand the Fehling-liquid had been accurately tested on invert- 

 sugar. Of the copper test solution 10 c.c. were diluted to 100 c.c. 

 and the reducing power of the blood-sugar solution was repeatedly 

 tested on 5 cc, until the liquid tfeing passed through a wet double 

 filter, gave no longer a red discoloration with an acetic acid solution 

 of potassium ferrocjanid. 



4. Removal of proteins. 



Proteins were separated from the blood after the old method of 

 Bernard (Na2S04 etc.). 



The following table shows the results obtained in this manner; 



TABLE I. 



Num- 

 ber 



Date 



Secretin 



Blood-sugar 



Remarks 



Dec. 1911 



12 cc 



12 „ 



14 „ 



15 „ 

 12 „ 



8 „ 



10 „ 



15 „ 



after 45 min. 0.14 % 

 „ 60 .. 0.082.. 



"I 



With absolute alcohol 

 substances lowering the 

 bloodpressure were ex- 

 tracted from the mucous 

 membrane. 



