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Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
10:53

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents

Published on: July 3, 2013

Calcitonin gene-related peptide suppresses the transient outward current in rat ventricular myocytes

M Stengl1, F Barták

  • 1Department of Physiology, Faculty of Medicine, Charles University, Pilsen, Czech Republic. stengl@lfp.cuni.cz

Pflugers Archiv : European Journal of Physiology
|February 24, 2001
PubMed

Insights

Calcitonin gene-related peptide (CGRP) reduces the transient outward current (Ito) in rat heart cells. This CGRP effect on Ito is concentration-dependent and involves protein kinase C signaling.

Area of Science:

  • Cardiology
  • Molecular Biology
  • Electrophysiology

Background:

  • Calcitonin gene-related peptide (CGRP) is a neuropeptide with known cardiovascular effects.
  • The precise mechanisms by which CGRP influences cardiac ion channels remain incompletely understood.
  • Understanding CGRP's impact on cardiomyocyte ion currents is crucial for cardiac function research.

Purpose of the Study:

  • To investigate the effects of CGRP on specific ion currents in rat ventricular cardiomyocytes.
  • To elucidate the signaling pathways involved in CGRP's action on these currents.

Main Methods:

  • Whole-cell, patch-clamp technique was employed on isolated rat ventricular cardiomyocytes.
  • The study examined the effects of CGRP on the transient outward current (Ito) and L-type calcium current (ICa,L).
  • Chelerythrine, a protein kinase C inhibitor, was used to probe the signaling pathway.

Main Results:

  • CGRP did not affect the amplitude or time course of the L-type calcium current (ICa,L).
  • CGRP significantly decreased the amplitude of the transient outward current (Ito) in a concentration-dependent manner.
  • The inhibitory effect of CGRP on Ito was reversible, membrane potential-independent, and prevented by chelerythrine, indicating protein kinase C involvement.

Conclusions:

  • CGRP selectively suppresses the transient outward current (Ito) in rat ventricular cardiomyocytes.
  • The mechanism of CGRP's action on Ito involves a protein kinase C-dependent pathway.
  • These findings contribute to understanding CGRP's role in regulating cardiac electrical activity.

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