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Figure 1.
Experimental setup. (A) Exposure paradigm and end points assessed during zebrafish development. Domoic acid (DomA) was intravenously microinjected at one developmental time. Arrows indicate the three developmental time points that were used across all experiments [1, 2, and 4 d postfertilization (dpf)]. Thinner arrowheads represent other developmental time points at which DomA was injected in selected experiments (1.5, 2.5, and 3 dpf). For each injection category, the associated ranges of injection times in hours postfertilization (hpf) were: 1 dpf (28–32.5 hpf), 1.5 dpf (35.5–39 hpf), 2 dpf (47–53 hpf), 2.5 dpf (60–64 hpf), 3 dpf (71–77 hpf), and 4 dpf (99–105.5 hpf). Mortality, morphological defects, the presence or absence of convulsions, pectoral flapping, and touch responses were recorded daily from the day after exposure to 5 dpf. (B) Apparatus used to assess startle responses to auditory/vibrational stimuli. A speaker with a bonded platform was sent a 3-ms, 1,000-Hz pulse, which was then delivered to a 16-well plate. A high-speed camera captured startle responses at 1,000 frames per second. (See the section “Equipment” in the Supplemental Material.) (C) Sample trace of the bend angle over time as a larva undergoes startle. Bend angle is estimated by measuring the changes in angles between three line segments that outline the larvae.