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the ligation of the duct. In I900oo, Schulze tied off small portions
of the pancreas in guinea-pigs, causing a complete atrophy of the
ligated glandular portion, which was replaced by connective
tissue, while the islands were unaffected. After eighty days
he finds mainly connective tissue with a few dilated ducts and
the normal areas of Langerhans. Since no glycosuria resulted
from his experiments, he drew the conclusion that the areas of
Langerhans are vascular glands of the type of the hypophysis,
having an internal secretion whose function is probably to reg-
ulate the sugar content of the blood. In I90o, Mankowski
repeated Schulze's experiment, tying two ligatures, and examin-
ing the portion between the ligatures, as well as the portion on
either side of the ligatures. His results and conclusions were
directly opposed to those of Schulze. He found both areas of
Langerhans and pancreatic tubules atrophic and sclerosed as a
result of his operation; as he notes an increase in the number of
islands during digestion and a diminution in the resting stage
of the pancreas, he decides that the islands are merely tempor-
arily changed acini.
In I902, Ssobolew ligated the duct and divided it between
the two ligatures in dogs, cats, and rabbits. In cats, he found
that the ducts generally reunited and became permeable before
any extreme atrophy could take place. He found rabbits most
favorable, since the duct could be tied and cut without injury to
the pancreas. In the rabbit's pancreas, he found, as did Schulze
in the guinea-pig, that the gland tissue became atrophic while
the areas were well preserved up to the four hundredth day, at
which time his observations ceased. At that time, the gland
consisted only of the normal areas, surrounded by connective
tissue containing the main duct. He describes the following
changes in the glandular tissue: (I) There is loss of zymogen
granules, protoplasm is homogeneous, and nuclei are irregular,
shrivelled, and deeply stained. (2) Cells disappear and membrana
propria collapses. (3) Centro-acinar cells are not seen after the
eleventh day. (4) The changes in the glandular cells consist of
atrophy, vacuolization, granular change, and sometimes indirect
cell division. (5) Cells of small ducts increase and to some