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

Calcium-dependent fluorescence transients during ventricular fibrillation.

T Stefenelli1, J Wikman-Coffelt, S T Wu

  • 1Department of Medicine (Cardiology), University of California, San Francisco.

American Heart Journal
|September 1, 1990
PubMed
Summary

Ventricular fibrillation in isolated hearts involves abnormal intracellular calcium ([Ca2+]i) transients, often triggered by premature beats and inotropic agents. Calcium levels remained stable or increased during fibrillation, refuting intracellular hypocalcemia.

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

[Research progress on the multidimensional regulation of gut microbiota on metabolism, immunity, and inflammatory response in metabolic associated fatty liver disease].

Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology·2026
Same author

[Application value of non-invasive prenatal diagnosis for recessive monogenic genetic diseases based on relative haplotype dosage changes].

Zhonghua yi xue za zhi·2025
Same author

[Application of ROC and PR curves in the evaluation of clinical diagnostic testing].

Zhonghua yu fang yi xue za zhi [Chinese journal of preventive medicine]·2022
Same author

[Effect of metformin combined with intermittent fasting on endoplasmic reticulum stress after cerebral ischemia-reperfusion in mice].

Zhonghua yi xue za zhi·2022
Same author

Arterial stiffness in acute COVID-19 and potential associations with clinical outcome.

Journal of internal medicine·2021
Same author

Synchronous renal cell carcinoma and pheochromocytoma presenting as acute decompensated heart failure.

Journal of postgraduate medicine·2019

Area of Science:

  • Cardiology
  • Physiology
  • Biochemistry

Background:

  • Ventricular fibrillation (VF) is a life-threatening arrhythmia.
  • Understanding the role of intracellular calcium ([Ca2+]i) dynamics during VF is crucial for developing effective treatments.
  • Inotropic agents and altered calcium levels are known to influence cardiac contractility and rhythm.

Purpose of the Study:

  • To investigate the characteristics of calcium transients during experimentally induced ventricular fibrillation in isolated rat and hamster hearts.
  • To determine the intracellular calcium ([Ca2+]i) levels during VF and their relationship with arrhythmogenic triggers.
  • To differentiate patterns of calcium transients associated with different types of VF.

Main Methods:

  • Surface fluorometry using INDO 1-AM was employed to measure calcium-dependent fluorescence transients.

Related Experiment Videos

  • Isolated perfused rat and hamster hearts were subjected to various pro-arrhythmic conditions, including inotropic agent pretreatment and elevated perfusate calcium.
  • Ventricular fibrillation was induced, and calcium transients were recorded during the arrhythmia.

    • Main Results:

    • Thirteen instances of VF occurred in 203 studies, often following pretreatment with agents like isoproterenol, dobutamine, norepinephrine, phenylephrine, digoxin, or high calcium.
    • Alternans of calcium transients were observed in 3 cases, and premature beats preceded VF in 6 cases, leading to increased [Ca2+]i and stronger contractions.
    • Two distinct VF calcium transient patterns were identified: Type 1 (fast, disorganized, small amplitude) and Type 2 (fast, multiform, polymorphous with amplitude changes).
    • [Ca2+]i remained constant or increased during VF, with no evidence of intracellular hypocalcemia.
    • Isoproterenol pretreatment led to end-diastolic [Ca2+]i levels, while other agents/conditions resulted in end-systolic [Ca2+]i levels.

    Conclusions:

    • Premature beats can trigger VF by increasing [Ca2+]i, leading to enhanced subsequent contractions.
    • Distinct patterns of intracellular calcium transients characterize different forms of ventricular fibrillation.
    • Inotropic agents that do not significantly elevate cyclic adenosine monophosphate appear to maintain higher intracellular calcium levels during fibrillation.