158 | Cerebellar and Cellular alterations induced by chronic self-administration of opioids in male Wistar rats

Cognition, Behavior, and Memory

Author: Mariana Stefania Serrano Ramírez | Email: mserrano@comunidad.unam.mx

Mariana Stefania Serrano-Ramírez , César J. Carranza-Aguilar , David Medina-Sánchez , Ana Débora Elizarrarás-Herrera , Jalil Rasgado-Toledo , Eduardo A. Garza-Villarreal

1° Universidad Nacional Autónoma de México, Instituto de Neurobiología

“Introduction: The cerebellum is currently considered as an integrating system that supports cognitive and emotional functions. In opioid use disorder, it activates the μ receptor in the cerebellum. So how does chronic opioid use affect the cerebellum? Our hypothesis is that there will be changes in the volume of the cerebellum, and there will be a decrease in neurons and astrocytes.
Material and Methods: Eleven male Wistar rats at P35 were used, they underwent jugular vein cannulation (6 control and 5 consumption) for self-administration in automated cages (Med-Associates model ENV-018V). Modeling was performed in FR1 for a phase from PR9-4 to a maintenance phase with morphine (0.01 or 0.1 mg/kg/infusion) or saline (0.9%) for the control group During FR1 . A 3D FLASH structural MRI sequence was performed before starting FR1 (P57), during FR1 (P70), and at the end of PR9-4 (P105) with the following parameters: TR = 30.76 ms, TE = 5 ms , angle of rotation = 10°, slice thickness = 25.6 mm, FOV = 28.2 x 19 x 25.6 mm, isometric voxel = 160 µm. Histology was performed in the regions that mark cerebellar volume changes for the cell count of neurons and astrocytes.
Results: The results of the magnetic resonance revealed structural changes of local volume such as the decrease of the cerebellar fissure and the increase of the superior cerebellar peduncle and the ventral spinocerebellar tract, as well as changes in the cell count of these areas.”