Dopamine modulates odor induced neural activity in the honey bee antennal lobes

EMILIANO MARACHIAN; MARTÍN KLAPPENBACH; FERNANDO LOCATELLI

Buenos Aires

Congreso; II Congreso de la Federación de Asociaciones Latinoamericanas de Neurociencias; 2016

1-   AiresBiogenic amines are key modulators of behavior andlearning in both vertebrates and invertebrates. In invertebrates dopamine representsthe internal signal of aversive stimuli while octopamine signals appetitivestimuli. We have shown in bees and crabs that both amines interact with eachother during memory formation. Dopamine, needed for aversive learning impairs appetitivememory, while octopamine needed for appetitive learning impairs aversive memory.We initiated a series of experiments aimed at understanding the mechanism bywhich dopamine impairs appetitive olfactory memory in bees. First we performedimmunohistochemistry using antibodies against tyrosine hydroxylase (TH) as a markerfor dopaminergic neurons. We found TH?positive neurons that enter the antenallobe (AL) coming from other brain regions, suggesting a dopaminergic modulationof the olfactory signals. We also found TH-positive somas within cell clusters thatare intrinsic to the AL network. Second, we performed calcium imaging of odorinduced signal in the AL. DA modified odor elicited activity in many differentways. Some glomeruli were not affected by DA at all. Some glomeruli showed increasedactivity during DA application. There was also a smaller subset of glomeruli inwhich normal signals were not restored after DA has been washed out. Theseobservations suggest that DA might impair appetitive olfactory memory, at leastin part, by affecting the perceptual quality of the conditioned odor.