Fig. 5. Amine-induced flight motor activity. Top traces: initial response to bath application; lower traces: expanded excerpts of electromyograms, as in Fig. 1. (A) Octopamine (500 mmol l^–1), (B) dopamine (200 mmol l^–1) and (C) tyramine (10 mmol l^–1) all induce fictive flight, but not (D) serotonin (10 mmol l^–1) or (E) the precursor amino acid tyrosine (10 mmol l^–1). (F) Atropine (10 mmol l^–1) blocks flight initiation by octopamine. Scale bar, 10 s upper traces, 100 ms lower traces.