title: Cellular communication and heterogeneity in pancreatic islet insulin secretion dynamics.
abstract: Coordinated pulses of electrical activity and insulin secretion are a hallmark of the islet of Langerhans. These coordinated behaviors are lost when β cells are dissociated, which also leads to increased insulin secretion at low glucose levels. Islets without gap junctions exhibit asynchronous electrical activity similar to dispersed cells, but their secretion at low glucose levels is still clamped off, putatively by a juxtacrine mechanism. Mice lacking β cell gap junctions have near-normal average insulin levels, but are glucose intolerant due to reduced first-phase and pulsatile insulin secretion, illustrating the importance of temporal dynamics. Here, we review the quantitative data on islet synchronization and the current mathematical models that have been developed to explain these behaviors and generate greater understanding of the underlying mechanisms.
authors.affiliation: Department of Bioengineering and Barbara Davis Center, University of Colorado Anschutz Medical campus, Aurora, CO, USA. Electronic address: richard.benninger@ucdenver.edu.
authors.forename: Richard K P
authors.initials: RK
authors.lastname: Benninger
authors.affiliation: Department of Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN, USA. Electronic address: dave.piston@vanderbilt.edu.
authors.forename: David W
authors.initials: DW
authors.lastname: Piston
mesh_terms: D000818:Animals; D002450:Cell Communication / Q000502:physiology*; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D007515:Islets of Langerhans / Q000378:metabolism*; D051379:Mice; D008962:Models, Theoretical
chemical_list: D007328:Insulin
keywords: calcium waves; computer modeling; fluorescence; islet of Langerhans; microscopy