AJP - Gastrointestinal and Liver Physiology, Vol 249, Issue 4 519-G527, Copyright © 1985 by American Physiological Society
Internal biliary diversion improves glucose tolerance in the rat
G. Manfredini, M. Ermini, L. Scopsi, F. Bonaguidi and E. Ferrannini
The gastrointestinal tract is known to generate hormonal and neural signals
that can affect the endocrine function of the pancreas ("enteroinsular
axis"). The physiological circumstances under which this connection is
operative are still a matter of debate. We investigated the influence of
bile flow on glucose homeostasis in an experimental model of internal
biliary diversion. After laparotomy in 2-mo-old rats, bile flow was
diverted from the duodenum into the second jejunal loop with the use of a
plastic minicannula. Rats in which the cannula was implanted but not
connected with the common bile duct (sham operation) and rats receiving no
treatment were used as control groups. After surgery, the rats with the
biliary bypass weighed 10% less than the controls for 3 wk; afterwards and
until 9 mo later, operated and nonoperated animals had similar growth
curves. After the operation, fasting plasma glucose concentrations fell
significantly in the treated rats compared with both sham-operated and
control rats; likewise, the glycemic response to orally administered
glucose was lower in the treated group 1 wk after surgery. In contrast, no
significant difference was found in either the fasting or the
glucose-induced plasma insulin levels. Nine months after surgery, the same
three groups of animals received an oral glucose tolerance test, an
intravenous glucose tolerance test, and a fasting-refeeding test (24 h of
fast followed by standard, mixed feeding for another 24 h). On all three
tests, bile-diverted rats showed lower plasma glucose responses than either
sham-operated or control rats in the face of essentially similar plasma
insulin responses.(ABSTRACT TRUNCATED AT 250 WORDS)
