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Pflügers Archiv

, Volume 422, Issue 4, pp 413–415 | Cite as

Gap junctional conductance tunes phase difference of cholecystokinin evoked calcium oscillations in pairs of pancreatic acinar cells

  • Anaclet Ngezahayo
  • Hans-Albert Kolb
Short Communication Transport Processes, Metabolism and Endocrinology; Kidney, Gastrointestinal Tract, and Excrine Glands

Summary

Using the double whole-cell recording technique we measured the gap junctional conductance (gj), while simultaneously monitoring the cytoplasmic free calcium concentration ([Cai2+]) in isolated acinar cell pairs from the pancreas of mouse. Physiological concentrations of the secretagogue cholecystokinin-octapeptide (CCK-OP) elicited [Cai2+] oscillations and after a delay in the minute range reduced gj. The results provide the first evidence suggesting that gj regulates the phase difference (Δφ) of [Cai2+] oscillations between neighbouring cells not in an all or none process, but with decreasing absolute value of gj Δφ monotonically increases. CCK-OP induced electrical uncoupling as well as the corresponding increase of Δφ could be blocked completely by the protein kinase C inhibitor polymyxin B. The data support the hypothesis that Ca2+ flow through gap junctions synchronizes [Cai2+] oscillations between gap junctional coupled cells.

Key words

Double whole-cell recording Gap junctional conductance Ca-oscillations Phase difference Cholecystokinin 

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Copyright information

© Springer-Verlag 1993

Authors and Affiliations

  • Anaclet Ngezahayo
    • 1
  • Hans-Albert Kolb
    • 1
  1. 1.Faculty of BiologyUniversity of KonstanzKonstanzGermany

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