Islet metabolism: recent acquisitions.
Isolated pancreatic rat islets deprived of exogenous nutrients maintain a sustained rate of O2 consumption. Glucose exerts little effect upon the utilization of endogenous nutrients. It is proposed that, under physiological conditions circulating L-glutamine represents a major fuel to cover the basal energy expenditure of the islets. Exogenous L-glutamine, which is actively metabolized in the islets, also provides an adequate substrate for the reaction catalyzed by glutamate dehydrogenase. L-glutamine dramatically enhances insulin release evoked by those amino acids which cause allosteric activation of the latter enzyme, e.g. L-leucine or b(-)BCH.
D000596:Amino Acids / Q000494:pharmacology; D000818:Animals; D005973:Glutamine / Q000378:metabolism / Q000494:pharmacology; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D010101:Oxygen Consumption; D051381:Rats
D000596:Amino Acids; D007328:Insulin; D005973:Glutamine