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

authored by

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.

Organisation(s)

Department of Cell Physiology and Biophysics

External Organisation(s)

University of Konstanz

Type

Article

Journal

Pflugers Archiv European Journal of Physiology

Volume

422

Pages

413-5

No. of pages

3

ISSN

0031-6768

Publication date

01.1993

Publication status

Published

Peer reviewed

Yes

Electronic version(s)

https://doi.org/10.1007/BF00374302 (Access: Restricted)