Anti-diabetic Substance 



521 



For treatment of perfustates 1 made with 0.2 per cent. HC! 

 and improved extracts recently prepared by percolation, neither 

 of which contains much protein, the method of refinement yield- 

 ing best results is as follows : 



1. Excess of acid is neutralized to P H of 5.85. Acid meta- 

 proteins are thrown down. Fluid is filtered and filtrate immedi- 

 ately readjusted to P H of 4.1. 



2. Sodium chloride in the proportion of 1 gram salt to 3.5 

 grams pancreas used is added to the first filtrate and dissolved. 

 The fluid is then evaporated to dryness. 



3. Excess salt and proteins are left behind by successive 

 fractional extractions with 80 per cent, alcohol and evaporation 

 to dryness. 



4. The final residue is treated with a small volume of sterile, 

 distilled water and the reaction which is now about N/5 HC1, 

 readjusted to P H 4.1 (15 c.c. fluid = 2.1 c.c. N/10 NaOH to 

 phenolphthalein). The anti-diabetic substance is precipitated in, 

 a form which is insoluble in sterile distilled water but is readily 

 soluble in zveak acid or weak alkali. 



5. It is free of chlorides and gives none of the following 

 reactions for proteins : Biuret, Millon's, Xantho-proteic and 

 Hopkins-Cole. 



257 (2217) 



The fate of iletin in the animal body. 

 By G. W. PUCHER, K. F. CORI, and B. D. BOWEN. 



[From the Buffalo General Hospital, Buffalo, N. Y.] 



Fasting animals show a different counter regulation for iletin 

 than animals which received food. Rabbits with food plus 

 iletin may show lowering of the blood-sugar for periods of eight 

 hours. Convulsions have been observed as long as 14 hours 

 after the iletin injection. This indicates that iletin is not rapidly 

 destroyed or eliminated by the animal body. No change in the 

 tolerance for iletin was observed after a daily administration of 

 the extract for 83 days. 



i Murlin, J. R., Clough, H. D., Gibbs, C. B. F., and Stone, Neil C, Amer. 

 Jour, of Physiol, 1923, Ixiv, 348. 



