Table 1. Dose-effect analysis of QT and non-QT prolongation inducers.

COMPOUND	CONCENTRATION
	0.1 µM	1 µM	5 µM	10 µM	20 µM	50 µM
Terfenadine	N	B	A	A	HF	HF
Cisapride	N	N	A	VF	HF	HF
Astemizole	N	A	HF	HF	HF	HF
Haloperidiol	N	N	A	VF	VF	HF
Digitoxin	ND	ND	N	B	HF	HF
Nitrendipine	ND	N	B	B	VF	HF

Four QT prolongation inducers (Terfenadine, Cisapride, Astemizole and Haloperidiol) and 2 non-QT prolongation inducers (Digitoxin and Nitrendipine) were tested on 48 hpf zebrafish embryos. Predominant observed effects are indicated: normal heart rate (N), bradycardia (B), 2∶1 arrhythmia (A), ventricle failure (VF), heart failure (HF).