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

verfasst von: A Ngezahayo, H A Kolb
Abstract: Using the double whole-cell recording technique we measured the gap junctional conductance (gj), while simultaneously monitoring the cytoplasmic free calcium concentration ([Ca2+i]) in isolated acinar cell pairs from the pancreas of mouse. Physiological concentrations of the secretagogue cholecystokinin-octapeptide (CCK-OP) elicited [Ca2+i] oscillations and after a delay in the minute range reduced gj. The results provide the first evidence suggesting that gj regulates the phase difference (delta phi) of [Ca2+i] oscillations between neighbouring cells not in an all or none process, but with decreasing absolute value of gj delta phi monotonically increases. CCK-OP induced electrical uncoupling as well as the corresponding increase of delta phi could be blocked completely by the protein kinase C inhibitor polymyxin B. The data support the hypothesis that Ca2+ flow through gap junctions synchronizes [Ca2+i] oscillations between jap junctional coupled cells.
Organisationseinheit(en): Abteilung Zellphysiologie und Biophysik
Externe Organisation(en): Universität Konstanz
Typ: Artikel
Journal: Pflugers Archiv European Journal of Physiology
Band: 422
Seiten: 413-5
Anzahl der Seiten: 3
ISSN: 0031-6768
Publikationsdatum: 01.1993
Publikationsstatus: Veröffentlicht
Peer-reviewed: Ja
Elektronische Version(en): https://doi.org/10.1007/BF00374302 (Zugang: Eingeschränkt)

BibTeX

@article{37d0efd241764b788ac4cf4211788ed6,
title = "Gap junctional conductance tunes phase difference of cholecystokinin evoked calcium oscillations in pairs of pancreatic acinar cells",
abstract = "Using the double whole-cell recording technique we measured the gap junctional conductance (gj), while simultaneously monitoring the cytoplasmic free calcium concentration ([Ca2+i]) in isolated acinar cell pairs from the pancreas of mouse. Physiological concentrations of the secretagogue cholecystokinin-octapeptide (CCK-OP) elicited [Ca2+i] oscillations and after a delay in the minute range reduced gj. The results provide the first evidence suggesting that gj regulates the phase difference (delta phi) of [Ca2+i] oscillations between neighbouring cells not in an all or none process, but with decreasing absolute value of gj delta phi monotonically increases. CCK-OP induced electrical uncoupling as well as the corresponding increase of delta phi could be blocked completely by the protein kinase C inhibitor polymyxin B. The data support the hypothesis that Ca2+ flow through gap junctions synchronizes [Ca2+i] oscillations between jap junctional coupled cells.",
keywords = "Animals, Calcium/metabolism, Cholecystokinin/pharmacology, Intercellular Junctions/drug effects, Membrane Potentials/drug effects, Mice, Pancreas/cytology",
author = "A Ngezahayo and Kolb, {H A}",
year = "1993",
month = jan,
doi = "10.1007/BF00374302",
language = "English",
volume = "422",
pages = "413--5",
journal = "Pflugers Archiv European Journal of Physiology",
issn = "0031-6768",
publisher = "Springer Verlag",
number = "4",
}