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Fig. 1 Tricaine fails to block evoked muscle contractility.
A. The electrical stimulation set-up (ESS). Fish are placed within the central well aligned, when spontaneous motility permits, with their anteroposterior axis perpendicular to the electrodes. Schematic of the electric stimulus regime is shown below. B-D. Tail displacement (d) in embryos from wild type (B) or a fixe heterozygote incross sorted into motile siblings (C; chrnd+/? 97/132 = 73.5%) and immotile mutants (D; chrndsb13/sb13 35/132 = 26.5%). Movement was quantified from videos as measured displacement (d) of tail as shown (B-D, right panels) in superimposed stills of single fish before stimulation (black image) and at maximum displacement (false-coloured red image). Unanaesthetized motile fish move extensively, generally out of the field of view (indicated by break in Y-axis). Fish were measured before tricaine exposure, after exposure to 0.61 mM tricaine for 30 min and after ≤30 minutes of tricaine washout into fish water. Note altered Y-scale in D compared to B,C. E. Comparison of mutants with tricaine-treated individuals reveals a striking similarity in displacement. Error bars are SEM. Numbers of embryos are shown on bars. Scale bars = 0.1 mm.