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Computer Modeling of Heterogeneous β-Cell Populations

  • Arthur Sherman
  • Paul Smolen
Chapter
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 426)

Abstract

β-cells differ significantly with respect to their electrical and secretory properties (Pipeleers, 1992), leading us to consider whether heterogeneity may have functional significance for the behavior of β-cell populations, such as the natural unit, the islet of Langerhans. On the other hand, β-cells in islets behave essentially synchronously, at least with regard to electrical activity (Eddlestone et al., 1984) and cytosolic Ca2+ levels (Santos et al., 1991). Several questions arise:
  • How does the islet synchronize? Are the reported size and density of gap junctional connections adequate to produce synchrony?

  • What is the role of cell heterogeneity? Is it important for building the graded response to glucose or merely an obstacle that must be overcome in order to achieve coordinated behavior?

  • Does glucose increase insulin secretion by recruiting more cells (Pipeleers, 1992) into activity or by increasing the output of each cell (Beigelman et al., 1977)?

  • How is the oscillatory activity of the islet generated in the absence of a pacemaker?

Keywords

Electrical Activity Pancreatic Islet Electrical Coupling Current Clamp Coupling Conductance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • Arthur Sherman
    • 1
  • Paul Smolen
    • 1
  1. 1.Mathematical Research BranchNational Institutes of HealthBethesdaUSA

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