[Action of [3,14-L-selenocysteine, 8-D-tryptophan]-somatostatin on insulin and glucagon secretion of the isolated perfused pancrease of the Wistar rat].
By isolated perfused pancreas of Wistar rats the glucose (11 mmol/l) and arginine (10 mmol/l) stimulated insulin (IRI) and glucagon (IRG) secretion was measured in order to investigate the inhibitory activities of somatostatin-14 (SS 14) and the somatostatin analogue [3,14-L-seleno-cysteine, 8-D-tryptophan]-somatostatin (SeSS). SS-14 or SeSS (152.8 nmol/l) inhibit the glucose stimulated IRI secretion by 75 and 65%, respectively. Only the second phase of the biphasic arginine stimulated insulin secretion pattern by 40%. SeSS has under these conditions no effect, whereas 58 nmol/l SS-14 or SeSS show a suppressing effect on the first (20 and 55%, respectively) and second phase (65 and 85%, respectively) of the insulin secretion. Using 5.8 nmol/l SS-14 or SeSS the arginine stimulated IRG secretion was inhibited only in the second phase of the biphasic glucagon secretion pattern by about 40%. 58 nmol/l SS-14 or SeSS show an inhibiting effect on the first and on the second phase of secretion, in both cases about 50%. It is concluded that in the SS-14 molecule the sulfur of cysteine in position 3 and 14 can be exchanged by selenium without modifying the biological activities measured in the glucose or arginine stimulated IRI and IRG secretion in vitro. The D-Trp8 in the SeSS analogue does not show the typical better inhibitory action of D-Trp8-SS-14 on insulin and glucagon secretion compared with SS-14. Possibly the selenium in the SeSS analogue abolishes this effect.
D000818:Animals; D005260:Female; D005934:Glucagon / Q000378:metabolism*; D005947:Glucose / Q000494:pharmacology; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D010477:Perfusion; D051381:Rats; D011919:Rats, Inbred Strains; D013004:Somatostatin / Q000031:analogs & derivatives / Q000494:pharmacology; D013329:Structure-Activity Relationship
D007328:Insulin; D013004:Somatostatin; C049884:somatostatin, seleno-Cys(3,14)-Trp(8)-; D005934:Glucagon; D005947:Glucose
Zur Wirkung von [3,14-L-Selenozystein, 8-D-Tryptophan]-Somatostatin auf die Insulin- und Glukagonsekretion des isoliert perfundierten Pankreas der Wistar-Ratte.