Abstract: Objective To develop an in vivo thrombosis model in live zebrafish. Methods AB strain zebrafish at 2 days post fertilization (dpf) were treated with various concentrations of phenyl hydrazine (0.5 μmol/L, 1 μmol/L, 2 μmol/L, 4 μmol/L and 8 μmol/L) for 24 hours and the venous blood speed and thrombosis in zebrafish were qualitatively assessed under a dissecting microscope. Subsequently, venous thrombus was quantified through measuring red blood cells stained with o-Dianisidine staining in zebrafish heart. Untreated zebrafish and zebrafish treated with 0.1% ethanol (vehicle) were used as controls. Results Reduced venous blood speed and thrombosis were observed in all the groups of zebrafish treated with phenyl hydrazine at concentrations from 0.5 μmol/L from 8 μmol/L. Thrombosis in zebrafish treated with 0.5 μmol/L, 1 μmol/L, 2 μmol/L, 4 μmol/L and 8 μmol/L of phenyl hydrazine were(19.79±1.55)%, (43.28±1.82)%,(69.85±1.12)%, (70.56±4.60)% and (72.25±2.11)%, respectively. Conclusion Phenyl hydrazine can induce thrombosis in zebrafish with an optimum concentration at 2 μmol/L and this thrombosis model may be useful for rapidly in vivo drug screening in live zebrafish.

Key words: Zebrafish, Model, Phenyl hydrazine, Thrombus