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

Ion currents underlying sinoatrial node pacemaker activity: a new single cell mathematical model

S Dokos1, B Celler, N Lovell

  • 1Biomedical Systems Laboratory, University of New South Wales, Sydney, Australia.

Journal of Theoretical Biology
|August 7, 1996
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

Secondary flow in bifurcations - Important effects of curvature, bifurcation angle and stents.

Journal of biomechanics·2021
Same author

The stability of care preferences following acute illness: a mixed methods prospective cohort study of frail older people.

BMC geriatrics·2020
Same author

What influenced people with chronic or refractory breathlessness and advanced disease to take part and remain in a drug trial? A qualitative study.

Trials·2020
Same author

A systematic review and computational modelling analysis of unilateral montages in electroconvulsive therapy.

Acta psychiatrica Scandinavica·2019
Same author

Mirtazapine for chronic breathlessness? A review of mechanistic insights and therapeutic potential.

Expert review of respiratory medicine·2019
Same author

How many people will need palliative care in 2040? Past trends, future projections and implications for services.

BMC medicine·2017

A new mathematical model reveals the inward background sodium current (ib,Na) drives sinoatrial node depolarization. Other currents like i(f) are not essential for pacemaker activity, challenging previous findings.

Area of Science:

  • Cardiovascular Physiology
  • Computational Biology
  • Electrophysiology

Background:

  • The sinoatrial node (SAN) generates the heart's electrical impulse through autorhythmicity.
  • Understanding the ionic basis of SAN action potentials is crucial for cardiac electrophysiology.

Purpose of the Study:

  • To investigate the ionic currents responsible for SAN autorhythmicity using a novel single-cell mathematical model.
  • To update and refine existing models of SAN membrane currents based on extensive literature data.

Main Methods:

  • Developed a new single-cell mathematical model of the mammalian sinoatrial node.
  • Simulated spontaneous cardiac electrical activity and analyzed ionic current contributions.
  • Compared model outputs with existing electrophysiological data and literature findings.

Related Experiment Videos

Main Results:

  • The inward background sodium current (ib,Na) was identified as the dominant driver of pacemaker depolarization.
  • The hyperpolarization-activated current i(f) was found not essential for pacemaker activity.
  • L-type calcium current (iCa,L) inactivation significantly influences current characteristics, potentially correcting literature overestimations of outward background currents.

Conclusions:

  • The study provides a refined understanding of ionic mechanisms in SAN autorhythmicity.
  • The model highlights the primary role of ib,Na and questions the necessity of i(f) in pacemaker function.
  • Action potential characteristics are significantly determined by iCa,L and iK reversal potentials, with iCa,L and iNaCa sustaining the action potential.