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

Two pathways for Ca2+ channel gating differentially modulated by physiological stimuli.

S Richard1, F Tiaho, P Charnet

  • 1Department of Pharmacology, Washington University School of Medicine, St. Louis, Missouri 63110.

The American Journal of Physiology
|June 1, 1990
PubMed
Summary
This summary is machine-generated.

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

[Genesis of cardiac sinus automaticity and therapeutic perspectives].

Archives des maladies du coeur et des vaisseaux. Pratique·2018
Same author

Honeybee locomotion is impaired by Am-Ca<sub>V</sub>3 low voltage-activated Ca<sup>2+</sup> channel antagonist.

Scientific reports·2017
Same author

Autologous dendritic cells prolong allograft survival through Tmem176b-dependent antigen cross-presentation.

American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons·2014
Same author

[The imminent peril in the law of July the fifth 2011, two years later: the impact on health?].

L'Encephale·2014
Same author

Deletion of the Kv2.1 delayed rectifier potassium channel leads to neuronal and behavioral hyperexcitability.

Genes, brain, and behavior·2014
Same author

Double-band sarcomeric SHG pattern induced by adult skeletal muscles alteration during myofibrils preparation.

Journal of microscopy·2010
Same journal

Blood coagulation in fish.

The American journal of physiology·2011
Same journal

Renal tubular reabsorption, metabolic utilization and isomeric fractionation of lactic acid in the dog.

The American journal of physiology·2010
Same journal

The inactivation of placental toxin by human serum.

The American journal of physiology·2010
Same journal

Adrenal function following ovariectomy in the rat.

The American journal of physiology·2010
Same journal

Capillary permeability; perfusion of frog and guinea pig hind limbs.

The American journal of physiology·2010
Same journal

Evaluation of protective measures against sunburn.

The American journal of physiology·2010
See all related articles

Cardiac calcium channels (ICa) exhibit two distinct gating pathways, fast (ICa (fc)) and slow (ICa (sc)), regulated by voltage, frequency, and agonists. These pathways suggest a single channel type with dual gating mechanisms in rat ventricular myocytes.

Area of Science:

  • Cardiology
  • Molecular Biology
  • Electrophysiology

Background:

  • Voltage-gated Ca2+ channels are crucial for cardiac action potentials and tension.
  • Previous assumptions suggested a single cardiac Ca2+ channel type.
  • Recent evidence indicates the coexistence of multiple Ca2+ channel types in myocardial cells.

Purpose of the Study:

  • To investigate the kinetic properties of macroscopic Ca2+ current (ICa) in adult rat ventricular myocytes.
  • To determine if distinct ICa components represent different channel types or gating mechanisms.
  • To explore the regulation of these ICa components by membrane potential, stimulation frequency, and pharmacological agents.

Main Methods:

  • Electrophysiological recordings of macroscopic Ca2+ current (ICa) in isolated adult rat ventricular myocytes.

Related Experiment Videos

  • Analysis of ICa waveforms to identify distinct kinetic components (fast, ICa (fc), and slow, ICa (sc)).
  • Application of varying membrane potentials, stimulation frequencies, and pharmacological agents (beta-adrenergic agonists, BAY K 8644).

    • Main Results:

    • ICa waveforms comprise two kinetically distinct components: ICa (fc) and ICa (sc).
    • Properties suggest two gating pathways for a single high-threshold Ca2+ channel type, not distinct channels.
    • ICa (fc) is preferentially activated by hyperpolarized potentials and low frequencies, while ICa (sc) is favored by depolarized potentials and high frequencies.
    • Beta-adrenergic agonists and BAY K 8644 preferentially augment ICa (fc) and, to a lesser extent, ICa (sc).

    Conclusions:

    • Cardiac Ca2+ current is mediated by two distinct gating pathways (fast and slow) of a single high-threshold Ca2+ channel type.
    • These gating pathways exhibit differential regulation by membrane potential, stimulation frequency, and specific agonists.
    • Understanding these dual gating mechanisms provides insights into cardiac electrophysiology and drug modulation.