OCTOPAMINE DISTRIBUTION IN THE INSECT NERVOUS SYSTEM

Abstract— Octopamine distribution has been surveyed in the nervous systems of two insect species, the locust, Schistocerca americana gregaria , and the cockroach Periplaneta americana. It is essentially similar for both species, being highly localised in the ganglia of the ventral nerve cord. Large amounts of octopamine are also found in the optic lobes especially, in the locust where it is concentrated in the medulla of the optic lobe. Octopamine can also be shown to be associated with insect neurohae‐mal structures such as the corpora cardiaca and the neurohaemal organs of the medial nervous system. The significance of the distribution is discussed.