Intraspecific aggression is influenced in numerous animal groups by the previous behavioral experiences of the competitors. The underlying mechanisms are, however, mostly obscure. We present evidence that a form of experience-dependent plasticity of aggression in crickets is mediated by octopamine, the invertebrate counterpart of noradrenaline. In a forced-fight paradigm, the experience of flyi...

Intraventricular infusions of octopamine which raised brain octopamine concentrations more than 20 000-fold resulted in reductions in brain noradrenaline and dopamine by as much as 90% without affecting the alertness or activity of normal rats. As this reduction of brain catecholamines is much greater than any reported in hepatic coma, we do not believe that values observed in experimental hepa...

Functional imaging with genetically encoded calcium and cAMP reporters was used to examine the signal integration underlying learning in Drosophila. Dopamine and octopamine modulated intracellular cAMP in spatially distinct patterns in mushroom body neurons. Pairing of neuronal depolarization with subsequent dopamine application revealed a synergistic increase in cAMP in the mushroom body lobes...

Drosophila melanogaster is a widely used model organism for studying neurological diseases with similar neurotransmission to mammals. While both larva and adult Drosophila have central nervous systems, not much is known about how neurotransmitter tissue content changes through development. In this study, we quantified tyramine, serotonin, octopamine, and dopamine in larval, pupal, and adult fly...

Recent evidence suggests that flies' sensitivity to large-field optic flow is increased by the release of octopamine during flight. This increase in gain presumably enhances visually mediated behaviors such as the active regulation of forward speed, a process that involves the comparison of a vision-based estimate of velocity with an internal set point. To determine where in the neural circuit ...

The modes of action of the modulatory compounds octopamine, 5-hydroxytryptamine (5-HT) and proctolin on the frequency of the myogenic rhythm of the extensor-tibiae muscle of the hindleg of the locust, Schistocerca americana gregaria, have been investigated. 5-HT and proctolin increase the frequency of the myogenic rhythm and the results of the present study suggest that they may mediate their e...

Intraventricular infusions of octopamine which raised brain octopamine concentrations more than 20 000-fold resulted in reductions in brain noradrenaline and dopamine by as much as 90% without affecting the alertness or activity of normal rats. As this reduction of brain catecholamines is much greater than any reported in hepatic coma, we do not believe that values observed in experimental hepa...

Phosphorylation of a protein (or proteins) of molecular weight 120,000 in the Aplysia abdominal ganglion, as measured by incorporation of [(32)P] or [(33)P]sodium phosphate in vitro followed by separation of the phosphoproteins on sodium dodecyl sulfate-polyacrylamide gels, was specifically stimulated by incubation in the presence of the putative neurotransmitters octopamine or serotonin. The s...

The parasitic braconid wasp Cotesia congregata lays its eggs inside the body of the larval stage of its host, the moth Manduca sexta. The Cotesia congregata larvae develop within the hemocoel of their host until their third instar, when they emerge and spin cocoons and pupate on the outer surface of the caterpillar. From this time until their death approximately 2 weeks later, the Manduca sexta...