•Gr. Banting, Li.B. ^
f. G. H. Best, *-'*• _ JfLlT™"- ^-
' hypothesis underlying tnis series of experiments was first
formulated by one of us in IIovember, 1920^v/whiie reading an article
dealing with the relation of the Isles of Lungerhans to diabetes.^^
JFrom the passage in this article, which gives a resume' of degenerative
changes in the'acini of the pancreas following ligation of the ducts,
the idea presented itself that since the aeinous, but not the islet
tissue, degenerates after this operation, advantage might be taken of
this fact to prepare an active extract of islet tissue. The subsid-
iary hypothesis was that trypsinogen or its derivatives was antagonistic
to tne internal secretion of the gland. The failures of other inves-
tigutors in this much-worked field wj&Uthus accounted for.
The feasibility of the hypothesis having been recognised by
Professor J.J.H. Macleod, work was begun ,under his direction in May,
192lj in the Physiological Laboratory of the University of Toronto.
In this paper no attempt is made to give a complete review of the
literature. A short resume, however, of some of the outstanding articles
which tend to attribute to the Isles of Langerhans the control of car-
bohydrate metabolism, is submitted.
In 1889 Mering and Minkowski N^Xfound that total pancreatectorny
in dogs resulted in severe and fatal diabetes. Following this, many
different observers experimented with animals of various species and
found in all types examined, a glycosuria and fatal caohexia after this
,G.B., then Assistant in Physiology at Western University, London, Ontario