Pflügers Archiv

, Volume 411, Issue 1, pp 53–57 | Cite as

Calcium and secretagogues-induced conductances in rat exocrine pancreas

  • C. Randriamampita
  • M. Chanson
  • A. Trautmann
Transport Processes, Metabolism and Endocrinology; Kidney, Gastrointestinal Tract, and Exocrine Glands

Abstract

The electrical properties of single acinar cells isolated from rat pancreas were studied with the whole-cell tight-seal recording method. Under resting conditions, the relative permeabilities of Cl and K werePcl/PK≅3. At 1 μM internal calcium, a Ca and voltage-dependent Cl conductance was activated. At 10 μM internal calcium, the major conductance was selective for cations. It was not voltage-dependent. Acetylcholine and cholecystokinin induced an increase of internal Ca which in turn activated either only a Cl conductance or both Cl and cationic conductances. The secretagogue-induced conductance was increased to a variable extent by depolarisation. The absence of K channels activated by internal calcium indicates that, in pancreatic acinar cells, the mechanism of fluid secretion differs from that observed in other exocrine glands.

Key words

Patch-clamp Acetylcholine Cholecystokinin Fluid secretion 

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Copyright information

© Springer-Verlag 1988

Authors and Affiliations

  • C. Randriamampita
    • 1
  • M. Chanson
    • 2
  • A. Trautmann
    • 1
  1. 1.Laboratoire de NeurobiologieEcole Normale SupérieureParisFrance
  2. 2.Department de Morphologie, Institut d'Histologie et d'EmbryologieCentre Médical UniversitaireGeneve 4Switzerland

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