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Glucagon and Insulin Metabolism in Cirrhotic Patients
Takanori Yoshida, Koichi Ninomiya, Toshifumi Matsumoto, Dolgor Baatar,
Toshio Bandoh, Seigo Kitano
First Department of Surgery
Oita Medical University
Oita, Japan
Abstract
Background/Aims:
The aim of this study was to investigate glucagon and insulin metabolism in
order to clarify the mechanisms that lead to hyperglucagonemia and hyperinsulinemia
in cirrhosis.
Methodology:
Splanchnic output and metabolic clearance rates were studied in 16 cirrhotic
patients and 5 non-cirrhotic controls. Splanchnic glucagon and insulin output
into the portal circulation were calculated by the difference between portal
venous and systemic arterial concentration multiplied by portal plasma flow.
The metabolic clearance rate was calculated as the ratio of output to systemic
arterial concentration. Portal blood flow was measured by continuous local thermodilution.
Results:
Arterial glucagon levels were higher in cirrhotics than in controls. Glucagon
output was triple of that found in controls (52.4±7.0 vs 17.7±2.9
ng/min, p<0.05). Both groups exhibited similar metabolic clearance rates
of glucagon. Systemic arterial insulin values were higher in cirrhotics than
in non-cirrhotics. Insulin output was not significantly different between the
two groups. However, metabolic clearance of insulin in cirrhotics was reduced
to one half of the rate found in controls (237.0±39.8 vs. 450.5±17.5
mL/min, p<0.05).
Conclusions:
Hyperglucagonemia in cirrhotic patients results from increased pancreatic output,
while hyperinsulinemia results from decreased insulin clearance.
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