D-013 | The forebrain of the big hairy armadillo (Chaetophractus villosus) following the Prosomeric rules.

Cellular and Molecular Neurobiology
Author: Sofía Labegorra | Email: francoluceroarteaga@hotmail.com

Sofía Labegorra^1°, Franco Lucero Arteaga^1°2°, Ana Inés Portu^1°,  Mariela Mondino^1°, Mónica Alejandra Boeris^1°, Ana Abrego Alvarez^1°, Valentina Heck^1°,  Bruno Ribeiro Do Couto^4°, Miguel Ángel García-Cabezas^3°, José Luis Ferrán^4°

^1° Centro de producción de Animales de Experimentación, Facultad de Ciencias Veterinarias, Universidad Nacional de La Pampa.
^2° Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
^3° Department of Anatomy, Histology and Neuroscience, School of Medicine, Autonomous University of Madrid, Madrid, Spain.
^4° Department of Human Anatomy and Psychobiology, School of Medicine, University of Murcia, Murcia, Spain. Institute of Biomedical Research of Murcia –IMIB, Virgen de la Arrixaca University Hospital, Murcia, Spain.

The big hairy armadillo is a species native to South America, characterized by having its body covered in a mixture of tough armor plates and thick fur, which helps protect it from predators and harsh environments. The big hairy armadillo is a nocturnal and omnivorous animal. Prosomeric rules dictate that the neural tube is regionalized along its anteroposterior axis giving rise to neuromeric units. Each neuromeric unit is regionalized along its dorsoventral axis into the roof, alar, basal, and floor plates. Our aim was to define the anteroposterior and dorsoventral subdivisions of the forebrain of the armadillo following prosomeric rules. To this end, the analysis was performed using immunoreactions with Tyrosine Hydroxylase (TH), Calbindin (CB), Calretinin (CR) and NeuN immunoreactions; but also, Nissl staining plus ACHe and Gallyas reactions. The study allowed to identify main prosomeric (p) subdivisions such as secondary prosencephalon (peduncular and terminal prosomeres), prethalamus(p3), thalamus (p2), pretectum (p1) and midbrain; characterizing their main anatomical landmarks such as fornix, and retroflex tract between others. Additionally, the study revealed some specific derivatives that are candidates to be homologous with other vertebrates. The study identified the main conserved forebrain neuromeres, but also opened the opportunity to begin in-deep studies to characterize the main derivatives of the Xenarthra. Grant: Fundación Seneca (21903/PI/22).