dog was reduced from .30 to normal and the urine became sugar free.
This was repeated both in the same dog and in other de-pancreatised
dogs with a similar result.
Carlson has found that in pregnant bitches de-pancreatised near
term that glycosuria did not develop until the pups were born. (Allan
was unable to confirm this result.) Ibraham was unable to find proteo-
lytic enzymes in the pancreas of the foetus' of under four months develop-
However, this finding gave us access to large quantities of potent
extract and abolished the delay and expense of obtaining the extract
by ligating the pancreatic ducts of the dog and waiting for degeneration.
Furthermore, it offered strong evidence that the active principle was
universal in the Animal Kingdom. (We have since tried the bovine
extracts on dogs, rabbits, and the human, and the results confirm this
Foetal calf extract was prepared by macerating the glands in Ringer's
solution and filtering until a clear solution was obtained. To get an
idea of the potency of the extract so obtained, we placed 50 gms. of
tissue in 250 c.c. of saline, macerated and filtered; 15 c.c. of this solution
were then diluted to 250 c.c. with saline. A 15 c.c. dose of this solution
reduced the percentage of blood sugar in a 10 kilogram dog from .40%
to .15% in three hours.
Up to this time the extract had been given intravenously. We found
that this extract when given subcutaneously gave a slower and more
prolonged, but not less'marked, fall in percentage of blood sugar.
In the endeavour to secure a sterile extract, we next tried the effect
of preservatives. We found that a .7% tricresol which is double the
strength used in preserving Diphtheria Anti-toxin, did not interfere
with the active principle. It was also found that the extract could be
Birkfeldted, but much of its potency was lost in this procedure.
Alcohol was then tried in the place of saline as an abstractive, and
it was found that the active principle was soluble. This was an im-
portant fact for it led us to believe that by the use of alcohol, we could
extract the active principle from the whole gland. Consequently, we
macerated a whole beef pancreas immediately after the death of the
animal in 95% alcohol. After allowing it to stand 12 hours, the liquid
was squeezed out and filtered until clear. This solution was then evapo-
rated to dryness in a warm air current. The resin-like residue was re-
dissolved in saline and injected subcutaneously into a diabetic dog.
The percentage of blood sugar fell from .35 to .08 in three hours and the
urine became sugar free. This was repeated with similar results. We
had thus obtained from-the whole gland an extract of the active principle
which, when washed with toluol, gave a brownish powder, which could
be kept sterile, which was soluble in saline, and which in minute doses
(50 mgms.) gave a pronounced effect on the blood of sugar.