Pflügers Archiv

, Volume 424, Issue 2, pp 195–197 | Cite as

Enhancers of cytosolic cAMP augment depolarization-induced exocytosis from pancreatic B-cells: evidence for effects distal to Ca2+ entry

  • Kevin D. Gillis
  • Stanley Misler
Short Communication Molecular and Cellular Physiology


We have investigated the effects of cAMP enhancing agents on depolarization-induced membrane capacitance increases (ΔCm in single rat pancreatic B-cells. Concentrations of IBMX, 8-CPT cAMP and forskolin, which enhance cAMP and insulin release, all enhance depolarization-induced ΔCm's seen in response to single voltage-clamp pulses and reduce the depression of ΔCm responses often seen with trains of pulses. These effects often occur in the absence of changes in peak Ca2+ current or the total Ca2+ charge entry during the depolarizing pulse. These data suggest that cAMP modulating maneuvers may directly affect the mechanism of insulin granule mobilization into a readily releasible store or fusion at a discharge site.


Depression Human Physiology Forskolin Insulin Release Discharge Site 
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Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • Kevin D. Gillis
    • 1
  • Stanley Misler
    • 1
  1. 1.Departments of Medicine (Jewish Hospital) and Cell Biology/PhysiologyWashington University Medical CenterSt. LouisUSA

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