Distribution of glutamate receptors in the posterodorsal medial amygdala of adult male rats.
The rat posterodorsal medial amygdala (MePD) has a remarkable neuronal plasticity and responds to olfactory/pheromonal stimuli to modulate emotional and reproductive behaviors. Glutamate is locally released by incoming sensorial pathways to establish and enforce synaptic inputs. Here, we combined DiI dye and immunolabeling procedure under confocal microscopy to describe the presence and distribution of glutamate receptors on neurons of the MePD of adult male rats. Western blot analysis interrogated binding specificity. Both AMPA (GluA1-4 subunits) and NMDA (GluN1 subunit) receptors were immunolabeled on cell bodies and along proximal and distal dendritic shafts. AMPA receptors were mainly observed on mushroom and stubby/wide spines, whereas NMDA receptors were found on thin spines. Colocalization of AMPA and NMDA receptors occurred in some spines. Filopodium did not show immunolabeled puncta on it. Our results are different from the distribution of glutamate receptors in the amygdaloid lateral nucleus, an upstream area involved with emotional processing, and suggest a region-specific excitatory transmission at proximal and distal dendritic branches. Altogether, these data provide new information for synaptic processing in the MePD likely related to the modulation of social behavior in rats.
Department of Basic Sciences/Physiology, Federal University of Health Sciences of Porto Alegre (UFCSPA), Brazil.
Francine
F
Dalpian
Laboratory of Synaptic Structure, Laboratory of Synaptic Structure, Departments of Pathology and Forensic Medicine and Neuroscience and Behavior, Ribeirão Preto School of Medicine, University of São Paulo (FMRP-USP), Brazil.
Janaina
J
Brusco
Department of Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.
Maria Elisa
ME
Calcagnotto
Laboratory of Synaptic Structure, Laboratory of Synaptic Structure, Departments of Pathology and Forensic Medicine and Neuroscience and Behavior, Ribeirão Preto School of Medicine, University of São Paulo (FMRP-USP), Brazil. cello@fmrp.usp.br.
Jorge E
JE
Moreira
Department of Basic Sciences/Physiology, Federal University of Health Sciences of Porto Alegre (UFCSPA), Brazil. rasiafilho@pq.cnpq.br, aarf@ufcspa.edu.br.
Alberto A
AA
Rasia-Filho
D000679:Amygdala / Q000737:chemistry*; D000818:Animals; D015153:Blotting, Western; D005455:Fluorescent Antibody Technique; D008297:Male; D018613:Microscopy, Confocal; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000032:analysis*; D016194:Receptors, N-Methyl-D-Aspartate / Q000032:analysis*
D018091:Receptors, AMPA; D016194:Receptors, N-Methyl-D-Aspartate