Modulation of Piriform Cortex Neuronal Activity by Inputs from Basolateral Amygdala and Lateral Entorhinal Cortex

NOEL FEDERMAN; ANTONIA MARIN-BURGIN; OLIVIA PEDRONCINI

Córdoba, Córdoba

Congreso; XXXIII Sociedad Argentina de Investigación en Neurociencias (SAN); 2018

Sociedad Argentina de Investigación en Neurociencias

Piriform cortex is the main region of the olfactory cortex where olfactory information is encoded. It receives sensory afferences from the olfactory bulb but also from other higher order brain regions such as the entorhinal cortex and the amygdala. Here we study how the basolateral amygdala (BLA) and the lateral entorhinal cortex (LEC) are functionally connected to the posterior piriform cortex (pPC). We infected the BLA and the LEC with adeno-associated virus expressing channelrhodopsin (ChR2-AAV) under CamKIIa or Parvalbumin promoters to activate either excitatory or inhibitory neurons respectively. We recorded postsynaptic currents and spiking in different principal neurons of the pPC in response to photostimulation. We found that both excitatory and inhibitory long range projections coming from the BLA synapse preferentially onto pyramidal neurons of the deep layers of pPC and do not contact semilunar neurons. Moreover, we discover that inputs from both BLA and LEC can modulate the spiking activity of pPC neurons evoked by electric stimulation of the afferent pathway. Deciphering the interaction between sensory ?bottom-up? and ?top-down? projections from higher brain areas will shed light on the understanding of how the brain could adaptively shape sensory cortical activity according to behavioral needs.