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CONTENTS
INTRODUCTION
When the scientific body that awards the Nobel prize each year met to consider the award for 1923, there was no question or debate as to the discovery that merited the honor. The prize was granted to Doctors F. G. Banting and J. J. R. MacLeod of Toronto for their work in the discovery of insulin, and each immediately donated one-half the award to colleagues who had shared in this discovery, Doctors C. H. Best and J. B. Collip.
In November, 1920, Dr. Banting, who had returned from war service, was practicing medicine in London, Ontario, and was demonstrating physiology in the medical school of Western University at that place. While reading an article in a surgical magazine, he chanced on a sentence which aroused the train of thought that finally led to his discovery of insulin—a substance that means a longer and more satisfactory life to diabetics.
The article which he read concerned a gland, known as the pancreas, that lies close to the stomach and the upper part of the intestines. This gland is composed of two portions, one of which creates a juice poured into the intestine, which aids in the digestion of food; it is the external secretion and it contains trypsin and two other digestive ferments. The pancreas contains also certain cells which, when seen through the microscope, are marked off from the remaining tissue and which are known by the peculiar name “Islands of Langerhans,” the latter being the name of their discoverer.
Diabetes centuries old.—Now diabetes is no new disease.
It was described by Aretaeus, a Greek who lived in the third century, A.D., and hundreds of scientists have worked steadily on the problem ever since that time. Indeed the history of the discovery of insulin is typical of all great medical discoveries of modern times. It represents the summation of a vast amount of knowledge contributed bit by bit by scientists all over the world. When Banting conceived his idea, he took it to Dr. MacLeod, director of physiologic research in the University of Toronto. Professor MacLeod, seeing the possibilities in the investigation, gave him opportunity to work, and provided him with a young assistant, Dr. C. H. Best. The particular problem on which they were to work was the extraction from the pancreas of another secretion, an internal secretion, not poured by the pancreas through a special duct into any other organ or to the exterior, but going instead into the blood stream.
Pancreas yields substance.—Previous investigations had indicated that this secretion was manufactured in the Islands of Langerhans. It was known that when the tube which carries the external secretion—trypsin—was tied, the trypsin would back up into the pancreas, and by its digestive action would destroy the glandular tissue, leaving an organ which consisted chiefly of island tissue.