Characterization of purinergic receptor-evoked increases in intracellular Ca2+ transients in isolated human and rodent insulin-secreting cells

Squires, Paul E. and James, R. F. L. and London, N. J. M. and Dunne, M. J. (1997) Characterization of purinergic receptor-evoked increases in intracellular Ca2+ transients in isolated human and rodent insulin-secreting cells. Advances in Experimental Medicine and Biology, 426 . pp. 173-179. ISSN 0065-2598

Full content URL: http://link.springer.com/chapter/10.1007%2F978-1-4...

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Item Type:Article
Item Status:Live Archive

Abstract

In vivo many factors determine the regulation of insulin secretion from the β-cells of the pancreatic islets of Langerhans. The most predominant influence is a rise in the concentration of plasma glucose, which will promote secretion by mechanisms associated with Ca2+ influx across the plasma membrane. Insulin release is also governed by changes in the concentration of circulating amino acids, gastrointestinal hormones, neuropeptides and neurotransmitters. These influences are important avenues for β-cell regulation as they not only provide a link between the gastrointestinal tract and the pancreatic islets — the enteroinsular axis, but they also govern the neurohormonal control of secretion. For many years it has been recognised that extracellular ATP is a potent insulin secretagogue. In vitro it has been demonstrated using rodent and clonal insulin-secreting cells that purinergic receptor activation is coupled to an increase in [Ca2+]i. However, few studies have examined intracellular Ca2+ signalling in isolated human insulin-secreting cells. In a recent paper we have shown that ATP and other agonists of the purinergic receptor evoke marked increases in [Ca2+]i in β-cells isolated from transplantable human islets of Langerhans. In this paper we examine: (i) the purinergic receptor subtype present in human tissue, (ii) compare purinergic receptor-evoked increases in [Ca2+]i in both rodent and human β-cells and (iii) demonstrate that intracellular Ca2+ signals can also be recorded in cryopreserved human β-cells originally isolated from cadaver organ donors.

Keywords:Insulin-Secreting Cells, Ca2+, Ca2+ transients, purinergic receptor-evoked increases, Islets of Langerhans, Ca2+ signaling
Subjects:C Biological Sciences > C990 Biological Sciences not elsewhere classified
Divisions:College of Science > School of Life Sciences
ID Code:14356
Deposited On:20 Jun 2014 10:38

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