Development of a robust insulin secretory response to glucose occurs during the early neonatal period. To determine if neuroendocrine agents play a role during this time, we studied the effects of selected peptides and neurotransmitters on insulin release and polyphosphoinositide metabolism in islets isolated from 1- and 3-day neonatal rats. Vasoactive intestinal peptide had no effect on glucose-stimulated release in either islet population. In contrast, sulfated cholecystokinin octapeptide (CCK-8) significantly enhanced glucose-induced insulin release in both islet groups. One-day islets were stimulated only by a concentration of 300 nM, whereas 3-day islets were responsive at 3 nM. Similar to CCK-8, there were clear differences in responses to carbachol between 1- and 3-day islets. One-day islets required a concentration of 200 μM for insulin release to be significantly greater than with glucose alone; 3-day islet insulin release was significant at 2 μM carbachol. Both agonists stimulated inositol phosphate accumulation in 3-day islets, but only CCK-8 caused a significant increase over glucose-induced levels in 1-day islets. These results indicate that islet responsiveness to CCK-8 and carbachol develops in parallel during the early neonatal period. This development may be linked to the maturation of a critical step of stimulus-secretion coupling through which these agents act.
Skip Nav Destination
Article navigation
Original Articles|
November 01 1989
Age-Dependent Stimulation of Neonatal Insulin Release and Inositol Phosphate Accumulation by CCK-8 and Carbachol
Donald J Fletcher;
Donald J Fletcher
Department of Anatomy and Cell Biology, School of Medicine, East Carolina University
Greenville, North Carolina
Search for other works by this author on:
Wesley H Rowley;
Wesley H Rowley
Department of Anatomy and Cell Biology, School of Medicine, East Carolina University
Greenville, North Carolina
Search for other works by this author on:
Susan J Pabst;
Susan J Pabst
Department of Anatomy and Cell Biology, School of Medicine, East Carolina University
Greenville, North Carolina
Search for other works by this author on:
Jack E Brinn
Jack E Brinn
Department of Anatomy and Cell Biology, School of Medicine, East Carolina University
Greenville, North Carolina
Search for other works by this author on:
Address correspondence and reprint requests to Donald J. Fletcher, Department of Anatomy and Cell Biology, School of Medicine, East Carolina University, Greenville, NC 27858-4354.
Diabetes 1989;38(11):1337–1342
Article history
Received:
November 07 1988
Revision Received:
June 26 1989
Accepted:
June 26 1989
PubMed:
2695370
Citation
Donald J Fletcher, Wesley H Rowley, Susan J Pabst, Jack E Brinn; Age-Dependent Stimulation of Neonatal Insulin Release and Inositol Phosphate Accumulation by CCK-8 and Carbachol. Diabetes 1 November 1989; 38 (11): 1337–1342. https://doi.org/10.2337/diab.38.11.1337
Download citation file:
30
Views