POSTNATAL PLASTICITY IN THE PARALAMINAR NUCLEUS OF THE PALLIAL AMYGDALA IN JUVENILE SWINE BRAIN

The aim of this study was to investigate the presence of immature cells and their phenotype in the pallial amygdala of juvenile swine brains by way of immunoreactivity for the microtubule-associated protein doublecortin (DCX), combined with the cell proliferation marker Ki-67 and different neuronal markers, including NeuN and the transcription factor COUP-TFII (NR2F2), critical for amygdalar development and adult phenotype maintenance. Our results showed the existence of numerous DCX+ cells along the external border of the basal amygdalar complex, adjacent to the amygdalar capsule, in an area identified as the swine paralaminar nucleus (PL). Most of DCX+ cells in PL expressed the neuronal marker NeuN and COUP-TFII. Paralaminar patches of DCX+ cells were more abundant at posterior levels, where they were continuous with chains of DCX+ cells with migratory-like morphology that appear to come from the subventricular zone of the temporal horn of the lateral ventricle. This ventricular/subventricular sector contained many cells coexpressing COUP-TFII and Ki-67 and DCX and Ki-67, suggesting that this might be the source of the immature cells found in the paralaminar nucleus and other parts of the pallial amygdala. Overall, these results show that the swine pallial amygdala shows a prolonged postnatal plasticity and contains a reservoir of immature neurons mainly located in the paralaminar nucleus and related vz/svz, resembling the situation seen in humans. Funding: AEI/MICIU_PID2023-151927OB-I00; FPU22/03133