AJP - Gastrointestinal and Liver Physiology, Vol 243, Issue 6 448-G454, Copyright © 1982 by American Physiological Society
Effects of high-fat diet on glucose metabolism in isolated pancreatic acini of rats
R. Bazin and M. Lavau
The purpose of the present study was to document the metabolism of glucose
and its responsiveness to insulin in isolated pancreatic acini from rats
fed either a low- or high-fat diet. The different steps investigated were
labeled glucose oxidation, lactate production, hexokinase activity, and
glucose transport, which was assessed by using both 3-O-methylglucose and
2-deoxyglucose. The acinar capacity to metabolize glucose (sum of CO2 plus
lactate) was decreased by 50% by feeding the rats a high-fat diet. The
impairment of glucose metabolism could not be explained by a defect in the
glucose phosphorylation step because hexokinase activity was not changed in
isolated acini from rats fed a high-fat diet. The effect of a high-fat diet
was entirely accounted for by a reduction in the glucose transport rate
that was achieved through a decrease in glucose transport Vmax with no
change in Km. We could not detect any effect of insulin on glucose
metabolism or 2-deoxyglucose uptake, whatever the diet composition. This
work establishes that a high-fat diet, known to markedly alter pancreatic
exocrine enzymes, also induces a large decrease in acinar glycolytic flux,
raising the question of the relation between these two sets of adaptive
changes.
