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Sauerbeck. Hansemann (I902), however, after ligating the duct
in ten dogs, states that the atrophy extends only a short distance
beyond the ligature and that the gland is later restored to a
considerable extent. The islands may be well preserved or they
may undergo fibrous degeneration. Lombroso (I905) tied and
cut the duct in dogs and pigeons and found the glandular paren-
chyma practically unchanged. He states also that the islands
show changes proportionate to those in the glandular tissue.
It would seem to me probable that the inconsistent results ob-
tained by these tu-o investigators are due either to incomplete
obstruction of the duct or to the regeneration of the duct which
is so commonly met with, since their operations seem to have
had so little effect on either the structure or the function of the
p.ancreas. Lépine (I905) comes to the conclusion that the acini,
as well as the areas of Langerhans, take part in furnishing the
internal secretion to the blood and bases his conclusion on the
following facts: (I) in some diabetics the insulæ are affected and
in others, the glandular tissue; (2) after ligation of the pan-
creatic duct or injection of oil into it, the glycolytic power of
the blood is greatly increased. As interference with the outflow
of the secretion can affect only the gland parenchyma and not
the islands, he considers this as sufficient proof that the acini as
well as the islands form the glycolytic principle which is given to
the blood.
Since the experiments of Schulze and Ssobolew and others
showed that by ligation of the duct and interference with the
outflow of the pancreatic secretion, a complete atrophy of the
glandular acini of the pancreas was caused, while the areas of
Langerhans remained unchanged, it seemed possible that by their
method the areas of Langerhans might be isolated in consider-
able portions of the pancreas and the physiologic action of their
extract determined; it was with this purpose that my experiments
were undertaken. My experiments were performed in great part
upon cats. Three were attempted upon guinea-pigs, but these
were unsuccessful, as the pigs died during the first three days
after the operation. In order to obtain as large an amount of ex-
tract as was consistent with the life and well-being of the operated