Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Elementary currents through Ca2+ channels in guinea pig myocytes.

A Cavalié, R Ochi, D Pelzer

    Pflugers Archiv : European Journal of Physiology
    |September 1, 1983
    PubMed
    Summary

    This study investigated calcium (Ca2+) and barium (Ba2+) currents in guinea pig heart cells, revealing how ion concentration affects channel behavior and kinetics. Findings show Ba2+ significantly alters Ca2+ channel properties, impacting cardiac electrophysiology.

    Related Concept Videos

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    [Traumatic subcutaneous emphysema of the face: the hazard of holding a sneeze].

    Revue medicale de Liege·2022
    Same author

    [Haemophilic ankle arthropathy : case reports and review of the literature].

    Revue medicale de Liege·2020
    Same author

    [Innovations in physical and rehabilitation medicine].

    Revue medicale de Liege·2020
    Same author

    The mode of transverse spread of contraction initiated by local activation in single crayfish muscle fibers.

    The Journal of general physiology·2009
    Same author

    Ionic channels formed by TRPC4.

    Handbook of experimental pharmacology·2007
    Same author

    Hyperpolarization and lysophosphatidylcholine induce inward currents and ethidium fluorescence in rabbit ventricular myocytes.

    The Journal of physiology·2002

    Area of Science:

    • Cardiovascular Physiology
    • Ion Channel Biophysics
    • Molecular Cardiology

    Background:

    • Ventricular myocytes are crucial for cardiac function, relying on ion channels for electrical activity.
    • Understanding calcium (Ca2+) and barium (Ba2+) currents is vital for elucidating cardiac electrophysiology.
    • The patch-clamp technique allows detailed analysis of single ion channel behavior.

    Purpose of the Study:

    • To investigate elementary Ca2+ and Ba2+ currents in guinea pig ventricular myocytes.
    • To determine the influence of varying Ba2+ and Ca2+ concentrations on channel kinetics and current properties.
    • To analyze the gating, inactivation, and permeation characteristics of cardiac Ca2+ channels.

    Main Methods:

    • Utilized the improved patch-clamp technique on cell-attached membrane patches of adult guinea pig ventricular myocytes.

    Related Experiment Videos

  • Employed high concentrations of Ba2+ or Ca2+ (50 or 90 mM) in pipettes for enhanced signal-to-noise ratio.
  • Analyzed elementary currents from patches containing single channels, examining responses to voltage steps.

    • Main Results:

    • Channel openings occurred in single events or bursts, with increased probability and decreased amplitude upon depolarization.
    • Barium (Ba2+) substitution for calcium (Ca2+) significantly increased slope conductance and peak current amplitudes.
    • Increased Ba2+ concentration shifted current-voltage and open probability-voltage relations, indicating altered channel gating and activation.

    Conclusions:

    • Barium (Ba2+) ions markedly influence cardiac Ca2+ channel gating, activation, and current amplitude compared to Ca2+.
    • Ca2+ channel inactivation can occur independently of divalent cation influx, forming a steady-state 'window' current.
    • The kinetics of cardiac Ca2+ channels are dependent on both voltage and the permeating ion (Ba2+ vs. Ca2+).