Figure 1

Injection of kainic acid into the bloodstream of 3 days post fertilization (dpf) zebrafish larvae. (A) A scheme of the set-up of kainic acid (KA) injection into 3 dpf zebrafish larvae. The larvae were anesthetized in 0.4 mg/mL tricaine and aligned in an agarose mold (left panel). KA mixed with dextran rhodamine B used as a tracer was injected into the zebrafish pericardium (right panel). (B) Survival of the larvae injected with 2.5, 5, 10, 20 mg/kg KA and vehicle (VHC) as a control. Significant larval death can be observed in a time-dependent manner. Statistical analysis between different doses injected was performed using Log-rank (Mantel-Cox) test (^*p < 0.05, ^**p < 0.01, ^****p < 0.0001). Data pooled from three independent experiments, total numbers include: VHC n = 60, KA 2.5 mg/kg n = 50, KA 5 mg/kg n = 84, KA 10 mg/kg n = 61, KA 20 mg/kg n = 83. (C) Quantification of morphological abnormalities after injection of 2.5, 5, 10 and 20 mg/kg of KA from 1 until 4 days post injection (dpi). Larval phenotype was classified in function of number of malformations—normal, mild, moderate and severe. The graphs include the percentage of dead larvae. Data were pooled from three independent experiments, total numbers include: VHC n = 60, KA 2.5 mg/kg n = 50, KA 5 mg/kg n = 84, KA 10 mg/kg n = 61, KA 20 mg/kg n = 83. (D) Representative images of KA-injected larvae showing normal, mild, moderate and severe phenotypes. Mild or moderate abnormalities included predominantly lack of swim bladder, while severe abnormalities consisted of jaw malformation, pericardial edema and yolk sac edema. Arrows indicating morphological abnormalities (lack of swim bladder, jaw malformation, pericardial edema, yolk sac edema, opaque brain). Scale bar 500 μm.