Long-term effect of prolactin treatment on glucose-induced insulin secretion in cultured neonatal rat islets
Nenhuma Miniatura disponível
Data
1997-07-22
Autores
Crepaldi, S. C. [UNESP]
Carneiro, E. M. [UNESP]
Boschero, A. C.
Título da Revista
ISSN da Revista
Título de Volume
Editor
Resumo
Insulin secretion and 45SCa2+ uptake and efflux were studied in neonatal rat islets maintained in culture for 7 or 19 days in the absence or presence of prolactin (PRL). Insulin secretion in response to glucose (G), leucine (Leu), arginine (Arg) and carbachol (Cch) was augmented after 7 and 19 days in culture, compared to basal secretion (G 2.8 mM), in both PRL- treated and control islets. However, the increase in insulin secretion induced by the above secretagogues was higher in islets cultured in the presence of PRL for 19 days. In PRL-treated islets, the 45Ca2+ content after a 5 min incubation in the presence of G, Leu, Arg and Cch was significantly higher than the control only in islets cultured for 19 days. Except with Arg, the 45Ca2+ uptake in PRL-treated islets after a 90 min incubation was also significantly higher than the control only in islets cultured for 19 days. Finally, Leu-induced alterations in the 45Ca2+ efflux were higher in PRL-treated than in control islets cultured for 7 or 19 days. In the absence of external Ca2+, the reduction in 45Ca2+ efflux induced by glucose was also significantly higher in PRL-treated than in control islets. This effect was slightly potentiated after 19 days in culture. These data further support the hypothesis that PRL treatment enhances maturation of the secretory mechanism in neonatal islets. This effect can be potentiated even more if the treatment is prolonged.
Descrição
Palavras-chave
Calcium, Insulin Secretion, Neonatal Rat Islets, PRL, arginine, carbachol, leucine, prolactin, animal cell, calcium transport, cell membrane permeability, cell proliferation, drug effect, enzyme activity, extracellular calcium, glucose oxidation, insulin release, nonhuman, pancreas islet beta cell, priority journal, rat, receptor upregulation, Animals, Animals, Newborn, Cells, Cultured, Glucose, Insulin, Pancreas, Prolactin, Rats, Time Factors, Animalia
Como citar
Hormone and Metabolic Research, v. 29, n. 5, p. 220-224, 1997.