248 



Scientific Proceedings (129) 



1 18 (2078) 



The action of iletin (insulin) on the blood sugar of pigeons. 



By HANNAH ELIZABETH HONEYWELL and OSCAR RIDDLE. 



[From the Department of Physiology, Columbia University, Neiv 

 York City, and the Carnegie Station for Experimental Evolu- 

 tion, Cold Spring Harbor, N. Y.] 



The recent preparation of relatively pure and standardized 

 extracts of the sugar reducing principle of the pancreas has 

 been accompanied by measurements of the time and extent of the 

 hypoglycemia resulting from its administration to the rabbit and 

 to man. 1 ' 2 These earlier studies already permit the employ- 

 ment of such extracts with confidence in their power temporarily 

 to reduce the blood sugar level in the higher animals. We present 

 here the result of 120 sugar determinations made after sub- 

 cutaneous injection of the extract into 35 pigeons of two species 

 and of a third (ataxic) variety. It was usually considered un- 

 necessary to make determinations of the sugar before injection 

 since the birds were handled in groups and the group averages 

 are known from extensive earlier work. These normal averages 

 are: 185 mgms. per 100 c.c. blood (or .185 per cent.) for com- 

 mon pigeons 3 ; 161 for ataxics; 150 for ring doves (unpub- 

 lished data). 



In a paper 4 accompanying this communication a pancreatic 

 extract of the standardized type (iletin; or insulin, Lilly) was 

 used continuously over a prolonged period in a test of its capacity 

 to suppress ovulations in the pigeon. Large doses were also used 

 to test the resistance of the bird to the extract. At the close 

 of that study the same group of birds and the same pancreatic 

 extracts were used for the purposes of the present study. One- 

 half of the blood samples were obtained by needle-puncture of 

 the heart and the other half by light bleeding from the upper 

 beak. MacLean's micro-method of sugar determination was 



1 Banting, Best, ColJip, Maeleod and Noble, Amer. Jour. Physiol., 1922 

 lxii, 163. 



2 Sutter and Murlin, Proc. Soc. Exp. Biol, and Med., 1922, xx, G8. 



3 Scott and Honeywell, Amer. Jour. Physiol., 1921, lv, 363. 



4 Riddle, Proc. Soc. Exp. Biol, and Med., 1923, xx, 5. 



