# Barium Chloride-Induced Cardiac Arrhythmia Mouse Model Exerts an Experimental Arrhythmia for Pharmacological Investigations

## TL;DR

This study introduces a mouse model using barium chloride to induce cardiac arrhythmias, which can help test new anti-arrhythmic drugs.

## Contribution

The study presents a reliable and alternative mouse model for pharmacological investigations of acute arrhythmias.

## Key findings

- Mice injected with BaCl2 developed ventricular bigeminy, tachycardia, and fibrillation similar to rats.
- Lidocaine and amiodarone successfully reverted BaCl2-induced arrhythmias in mice.
- The BaCl2-induced arrhythmia in mice is comparable to other induction methods across species.

## Abstract

Aim: Cardiac arrhythmias are among the most important pathologies that cause sudden death. The exploration of new therapeutic options against arrhythmias with low undesirable effects is of paramount importance. Methods: However, the convenient and typical animal model for screening the potential lead compound becomes a very critical modality, particularly in anti-arrhythmia. In this study, mice were intraperitoneally (i.p.) injected with BaCl2, CaCl2, and adrenaline to induce arrhythmia, and simultaneously compared with BaCl2-induced rats. Results: Electrocardiogram (ECG) showed that the majority of mice repeatedly developed ventricular bigeminy, ventricular tachycardia (VT), and ventricular fibrillation (VF) after BaCl2-injection as seen in rats. The ECG of mice developed ventricular bigeminy and VT after CaCl2 and AT after adrenaline i.p. injection. Additionally, acute cardiac arrhythmia after BaCl2 i.p. injection could be reverted by drugs (lidocaine and amiodarone) administration. Additionally, the different routes of administration for various chemical-induced arrhythmia in both mice and rats were also retrieved from PubMed and summarized. Comparing this approach with previous studies after the literature review reveals that arrhythmia of BaCl2-induced i.p. mice is compatible with the induction of other routes. Conclusions: This study brings an alternative experimental model to investigate antiarrhythmic theories and provides a promising approach to discovering new interventions for acute arrhythmias.