Gap junctions and expression of Cx36 Cx43 and Cx45 in the posterodorsal medial amygdala of adult rats
Mariana Zancan1, Taís Malysz1,2,3, Dinara J. Moura4, Ana Moira Morás4, Luiza Steffens4 and Alberto A. Rasia-Filho1,3,4
1Universidade Federal de Ciências da Saúde de Porto Alegre/DCBS-Physiology, 2Universidade Federal do Rio Grande do Sul/ICBS-Anatomy, 3Universidade Federal do Rio Grande do Sul/Graduate Program in Neurosciences and 4Universidade Federal de Ciências da Saúde de Porto Alegre/Graduate Program in Biosciences, Porto Alegre-RS, Brazil
Offprint requests to: Alberto A. Rasia-Filho, UFCSPA/Fisiologia, Sarmento Leite 245, 90050-170 Porto Alegre-RS, Brazil. e-mail: rasiafilho@pq.cnpq.br, aarf@ufcspa.edu.br
Summary. The posterodorsal medial amygdala (MePD) has a synaptic organization that dynamically modulates reproduction and other social behaviors in rats. Discrete gap junctions between glial cells were previously reported in the MePD neuropil. Connexins (Cx) are components of gap junctions and indicative of cellular electrical coupling. Here, we report the ultrastructural occurrence of gap junctions between neurons in the MePD and demonstrate the expression and immunofluorescent labeling of Cx36, Cx43 and Cx45 in this subcortical area of adult male rats. Few neuronal gap junctions were found in the MePD and, when identified, occurred between dendrites. On the other hand, there is a diffuse presence and distribution of punctate labelling for the tested Cxs. Puncta were visualized isolated or forming clusters in the same focal plane of cell bodies or along the MePD neuropil. The Cx36 puncta were found in neurons, Cx43 in astrocytes and Cx45 in both neurons and astrocytes. Our data indicate the presence of few gap junctions and different Cxs composition in the MePD. Because Cxs can assemble, form hemichannel units and/or serve as transcriptional regulator, it is likely that additional modulation of intercellular communication can occur besides the chemical transmission in the MePD of adult rats. Histol Histopathol 35, 395-403 (2020)
Key words: Extended amygdala, Connexin, Transmission electron microscopy, Immunofluorescence
DOI: 10.14670/HH-18-160