Pancreatic islet blood flow in normal and obese-hyperglycemic (ob/
ob) mice.
Carlsson, Per-Ola, Arne Andersson, and Leif Jansson.
Department of Medical Cell Biology, Uppsala University, Uppsala,
Sweden
APStracts 3:0164E, 1996.
The present study evaluated if a microsphere technique could be used
for islet blood flow measurements in anesthetized mice. As this was
confirmed, we applied the technique in different strains of mice.
Approximately 9 x 104 microspheres could be given without interfering
with mean arterial blood pressure. Mixing of the microspheres with
arterial blood was adequate, and the extraction of microspheres in
capillary beds was nearly 100%. In NMRI mice whole pancreatic blood
flow was estimated to 0.54+/-0.11 ml/min x g pancreatic tissue and
islet blood flow to 18+/-4 [mu]l/min x g pancreas (n=12
respectively), whereas corresponding values in lean C57Bl/6 mice were
twice as high. In C57Bl/6 mice glucose (3 g/kg IV) doubled islet
blood flow without affecting whole pancreatic blood flow, while no
effect was seen after an equimolar dose of 3-0-methyl glucose. In
obese-hyperglycemic C57Bl/6 mice islet blood flow was more than five
times higher than in the lean C57Bl/6 mice when expressed as blood
flow per g pancreas. However, when islet blood perfusion was
corrected for islet weight it was lower in the obese than in the lean
mice, suggesting an impaired ability in obese mice to increase blood
flow in concert with the increased islet mass. This may contribute to
the insufficient insulin secretion and resulting hyperglycemia seen
in these animals.
Received 12 March 1996; accepted in final form 25 July 1996.
APS Manuscript Number E125-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 21 August 1996