Maintenance of pancreatic endocrine cells of the neonatal rat: VII. The effect of 3-amino-3-deoxyglucose on insulin secretion from perifused B cells.
Monolayer cultures of the pancreas of the neonatal rat were maintained in TCM 199 medium, supplemented with 5.5 mM glucose, with or without 5 mM 3-amino-3-deoxyglucose, and perifused to examine the changes which occurred in the insulin secretory response during culture. On day 0, B cells showed a monophasic insulin secretion in response to 16.7 mM glucose, whereas in the presence of 200 nM 12-o-tetradecanoyl phorbol-13-acetate, 40 microM lysophosphatidylcholine, 10 microM forskolin or 1 mM 3-isobutyl-1-methylxanthine, the same dose of glucose stimulated insulin secretion in a biphasic fashion. Under culture conditions without 3-amino-3-deoxyglucose, the response to glucose totally disappeared after 7 days, and that to 10 mM of either leucine or 2-ketoisocaproate was as low as that of day 0. In contrast, B cells that had been cultured for 7 days in medium with 3-amino-3-deoxyglucose showed an adult-like biphasic pattern in response to glucose. When stimulated by glucose at a linear gradient concentration running from 0 to 20 mM, the B cells responded to increasing concentrations of glucose in a dose-dependent fashion. Further, the response of cAMP to glucose was increased by adding forskolin or 3-isobutyl-1-methylxanthine, which also enhanced the secretion of insulin under either a step-wise or slow-rise stimulation with glucose. The effect of 12-o-tetradecanoyl phorbol-13-acetate was also outstanding. Likewise, the addition of either leucine or 2-keptoisocaproate induced a striking increase in the secondary phase secretion as well as promoting the rates of glutamine oxidation within the cells. In conclusion, it is suggested that the high response to a wider variety of stimuli may represent the reaction of neonatal B cells to the cultural milieu rather than a process of physiological development, and these effects exhibited by 3-amino-3-deoxyglucose would be related to a change in the constituents of glycoproteins in the cells.
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005944:Glucosamine / Q000494:pharmacology; D005947:Glucose / Q000494:pharmacology; D005973:Glutamine / Q000378:metabolism; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D007651:Keto Acids / Q000494:pharmacology; D007930:Leucine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D007328:Insulin; D007651:Keto Acids; D005973:Glutamine; C014968:kanosamine; C013082:alpha-ketoisocaproic acid; D000242:Cyclic AMP; D007930:Leucine; D005947:Glucose; D005944:Glucosamine