Octopamine: presence in firefly lantern suggests a transmitter role.
The lantern of the adult firefly is innervated by a nerve supply with endings similar to other known monoaminergic nerves. However, catecholamines could not be detected in the nerve endings and noradrenaline and adrenaline were relatively weak agonists in eliciting a flash of light when applied to the lantern in vitro. Firefly lanterns were assayed for octopamine using a sensitive, specific enzymatic assay in which octopamine is enzymatically converted to 3H-synephrine and quantitated by liquid scintillation counting. The presence of substantial amounts (125 ng/g tissue) of octopamine was demonstrated and confirmed by thin layer chromatography. On the basis of this and earlier work, it is suggested that the nerves to the firefly lantern are octopaminergic.
D000818:Animals; D004175:Diptera / Q000032:analysis / Q000502:physiology*; D008297:Male; D008722:Methods; D009655:Octopamine / Q000502:physiology*
D009655:Octopamine