Table 2.

Similarities and differences of the zebrafish cardiac electrophysiology with the human cardiac electrophysiology.

Similarities with human cardiac electrophysiology	Differences to human cardiac electrophysiology
Cardiac AP has a clear plateau phase.	Absence of the phase 1 repolarization (ITo not expressed)
A distinct QT interval in ECG	The slow component of the delayed rectifier IKs is not expressed in the zebrafish heart.
Similar fundamental current systems (INa, ICaL, IK) are present in atrial and ventricular myocytes.	Large ICaT is present in zebrafish atrial and ventricular myocytes.
IKr and IK1 are the main repolarizing currents.	IK1 is mainly generated by Kir2.4 and Kir2.2a channels.
	IKr is mainly generated by erg2 (KCNH6) channels.
	The balance of inward currents: density of INa low and density of ICa high in comparison to the human heart