Caffeine and Dobutamine Challenge Induces Bidirectional Ventricular Tachycardia in Normal Rats

Author(s)

Zhang, C., & Zhang, Y.

Title

Caffeine and Dobutamine Challenge Induces Bidirectional Ventricular Tachycardia in Normal Rats

Date

2020

Publisher

Elsevier BV

Subject

Bidirectional ventricular tachycardia
Caffeine
Dantrolene
Dobutamine
Ventricular arrhythmia

Language

English

Abstract

Background

Bidirectional ventricular tachycardia (BD-VT) is an intriguing arrhythmia, characterized by a beat-to-beat alternation of the QRS polarity on electrocardiogram. Currently there is no simple BD-VT animal model.

Objective

We report a simple animal model of BD-VT induced by caffeine and dobutamine (C+D) challenge in normal rats in which the arrhythmia can be attenuated by dantrolene (a ryanodine receptor stabilizer) treatment, but not by the pacemaker channel blocker ivabradine treatment.

Methods

Adult (4–5 months old) Sprague-Dawley rats (both sexes) were randomized into C+D (n = 8, received caffeine 120 mg/kg intraperitoneally [IP] and dobutamine 60 μg/kg IP, sequentially) and control (n = 8) groups. In addition, a group of 7 rats were pretreated with dantrolene (10 mg/kg, IP) 30 minutes before the C+D challenge and another group of 8 rats were pretreated with ivabradine (5 mg/kg, IP) 30 minutes before the C+D challenge.

Results

C+D challenge induced spontaneous premature ventricular contractions (PVCs) in 7 of 8 rats and BD-VT (lasted 4.3 ± 2.9 minutes, terminated spontaneously) in 6 of 8 (75%) rats. No ventricular arrhythmia was induced in the control group (P < .05 vs C+D group). Dantrolene treatment significantly decreased BD-VT (1 of 7 rats in the Dantrolene+C+D group vs 6 of 8 rats in C+D group, P < .05). Ivabradine treatment did not affect C+D-induced BD-VT (7 of 8 rats in the Ivabradine+C+D group vs 6 of 8 in the C+D group, P > .05).

Conclusion

Caffeine and dobutamine challenge induces BD-VT in a majority of normal rats. Stabilizing cardiac ryanodine receptors with dantrolene treatment can significantly decrease the occurrence of BD-VT, but pacemaker channel blocker ivabradine treatment does not have effect in this animal model.

Source

Heart Rhythm O2, Volume 1, Issue 5, December 2020, pages 359-367

Rights

Copyright

© 2020 Heart Rhythm Society. Published by Elsevier Inc.

User license

Creative Commons Attribution – NonCommercial – NoDerivs (CC BY-NC-ND 4.0) | 
How you can reuse 

Format

PDF

Type

Text

Bibliographic Citation

Zhang, C., & Zhang, Y. (2020). Caffeine and dobutamine challenge induces bidirectional ventricular tachycardia in normal rats. In Heart Rhythm O2 (Vol. 1, Issue 5, pp. 359–367). Elsevier BV. https://doi.org/10.1016/j.hroo.2020.08.005

Files

PIIS2666501820301148.pdf

Citation

Zhang, C., & Zhang, Y. , Caffeine and Dobutamine Challenge Induces Bidirectional Ventricular Tachycardia in Normal Rats. Heart Rhythm O2, Volume 1, Issue 5, December 2020, pages 359-367, New York Tech Institutional Repository, accessed April 27, 2024, https://repository.nyitlibrary.org/items/show/3770

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