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Scientific Proceedings (130) 



theory were correct one should be able to demonstrate the hor- 

 mone in plant tissue which contained neither glycogen nor starch. 

 Professor F. J. Lewis very kindly suggested the onion as a type 

 plant which contains neither glycogen nor starch, and which is 

 also a well recognized glucose burner. The onion was therefore 

 used and the writer was successful in preparing extracts from 

 onion tissue which produced when administered to normal rab- 

 bits effects similar to those following the administration of yeast 

 extracts. A depancreatized dog was caused to have a normal 

 blood sugar for a period of many hours by the use of onion ex- 

 tract, and the urine was rendered practically sugar free for a 

 similar period. 



Encouraged by these results, the writer investigated tissues of 

 other plants and similar results were obtained in many instances. 

 Extracts made from yeast (either baker's or brewer's), green 

 onion tops, onion roots, barley roots, sprouted grain, green wheat 

 leaves, bean tops, and lettuce have been found to have similar 

 properties. 



The demonstration that a substance capable of producing hypo- 

 glycemia in normal rabbits and in the few cases tested out, a 

 definite fall in the blood sugar and a decrease in sugar excretion 

 of depancreatized dogs by extracts of plant tissues so widely 

 divergent in character as the above list indicates, justifies one in 

 assuming a hormone present in the above plant tissues and prob- 

 ably universally present in plant tissue. Such hormone would 

 be just as essential to the metabolism of sugar in the plant as a 

 similar hormone, produced in the higher animal by the islets of 

 Langerhans, is to the metabolism of sugar in the animal. 



The new substance, although in some ways similar in its prop- 

 erties to the active principle of the pancreas of animals, obviously 

 can not be known as "Insulin." In the official announcement 4 by 

 the Toronto group on the effects of extracts of pancreas on 

 diabetes, the name "Insulin" was given to an extract of animal 

 pancreas prepared by a definite process elaborated by the writer 

 and known as the "Collip method." Therefore it would seem 

 proper to suggest that this new hormone derived from plant 

 sources be called "Glucokinin." 



4 Banting, F. G., Best, C. H., Collip, J. B., Campbell, W. 1?.^ Fletcher, A. A., 

 Macleod, J. J. R., and Noble, E. C, Trans. Assoc. Am. Physicians, May, 1922. 



