1. Concentrations of @entity3776 and @entity16749 were studied in islets of Langerhans isolated from @entity35 pancreas and incubated in the presence of various agents that induce insulin release. 2. In response to rising concentrations of extracellular @entity413 (2-10mm) there is a linear increase in the intracellular concentration of @entity3776 , though this is not the case for @entity16749 , the intracellular concentration of which only increases when the external @entity413 concentration exceeds 5mm. 3. @entity11243 , @entity6212 and @entity1792 , all of which promote insulin secretion from isolated islets, increase the intracellular concentrations of @entity3776 and @entity16749 . The results obtained in the presence of @entity6212 and @entity1792 are compatible with an inhibitory effect of @entity1792 on islet-cell phosphofructokinase. 4. Theophylline and glucagon when incubated with islets in vitro promote insulin release and cause a rise in @entity16749 concentration and not in that of @entity3776 . 5. It is suggested that the further metabolism of @entity3776 through a pathway other than glycolysis is essential for insulin release. One such pathway involves its oxidation to @entity16749 , which seems to be a necessary accompaniment of insulin secretion due to @entity413 . The possibility that agents other than @entity413 promote insulin release by enhancing the oxidation of @entity3776 through this pathway is discussed.

Islet-cell metabolism during insulin release. Effects of @entity413 , XXXX , @entity6212 , @entity11243 , glucagon and theophylline.

@entity6212 :: ('MESH:C031492', 'Chemical') :: ['octanoate'] @entity16749 :: ('MESH:C008884', 'Chemical') :: ['6-phosphogluconate'] @entity1792 :: ('MESH:D019343', 'Chemical') :: ['citrate'] @entity11243 :: ('MESH:D014044', 'Chemical') :: ['Tolbutamide'] @entity35 :: ('10116', 'Species') :: ['rat'] @entity413 :: ('MESH:D005947', 'Chemical') :: ['glucose'] @entity3776 :: ('MESH:D019298', 'Chemical') :: ['glucose 6-phosphate']
@entity1792 :: (MESH:D019343,Chemical) :: ['citrate']
