While the zebrafish heart shares similarities with the human heart in action potential and major currents, significant differences exist in ionic current composition and molecular basis.
While the zebrafish heart shares qualitative similarities with the human heart in action potential and major currents, significant molecular and pharmacological differences necessitate caution and further research when using it as an electrophysiological model.
The zebrafish (Danio rerio) has become a popular model for human cardiac diseases and pharmacology including cardiac arrhythmias and its electrophysiological basis. Notably, the phenotype of zebrafish cardiac action potential is similar to the human cardiac action potential in that both have a long plateau phase. Also the major inward and outward current systems are qualitatively similar in zebrafish and human hearts. However, there are also significant differences in ionic current composition between human and zebrafish hearts, and the molecular basis and pharmacological properties of human and zebrafish cardiac ionic currents differ in several ways. Cardiac ionic currents may be produced by non-orthologous genes in zebrafish and humans, and paralogous gene products of some ion channels are expressed in the zebrafish heart. More research on molecular basis of cardiac ion channels, and regulation and drug sensitivity of the cardiac ionic currents are needed to enable rational use of the zebrafish heart as an electrophysiological model for the human heart.
Vornanen et al. (Tue,) conducted a review in Cardiac electrophysiology and arrhythmias. Zebrafish heart model vs. Human heart was evaluated. While the zebrafish heart shares similarities with the human heart in action potential and major currents, significant differences exist in ionic current composition and molecular basis.