Morphometric study of postnatal cerebellum treated with angiotensin II AT2 receptor antagonist

SOLER GARCIA, FLORENCIA M.; SANCHEZ, SUSANA; FUENTES, LUCIA

Tucuman

Congreso; TERCERA REUNIÓN CONJUNTA DE SOCIEDADES DE BIOLOGÍA DE LA REPÚBLICA ARGENTINA (XXXII JORNADAS CIENTÍFICAS DE LA ASOCIACIÓN DE BIOLOGÍA DE TUCUMÁN, XX JORNADAS CIENTÍFICAS DE LA SOCIEDAD DE BIOLOGÍA DECÓRDOBA, XXXIII JORNADAS CIENTÍFICAS DE LA SOCIEDAD DE B; 2015

Sociedas de Biologias Argentinas

The cerebellum has a striking morphology consisting of folia separated by fissures of different lengths. Since folia in mammals likely serve as a broad platform on which the anteriorposterior organization are built, it is important to understand how such complex morphology arises.Angiotensin II receptor type 2 in fetal and postnatal development has been related with neuronal differentiation. In cerebellum, AT2 receptors are located only in the Purkinje cells, which orchestrate the process of postnatal cerebellar corticogenesis and consequently in cerebellar development. Previous studies have shown changes in cerebellum morphology in treated animals with PD123319. The aim was to analyze the morphometrics characteristics of postnatal cerebellum treated with the antagonist. Rats during late pregnancy (G13-G21) were subcutaneously administered with PD 123319 (1.0 mg/kg/day) and vehicle (control). The offspring were sacrificed at postnatal 3, 5 and 8 days (P3-P5-P8). Slices from cerebellum (14µm) were stained with H&E. The cerebellum perimeter and area have shown significant differences between treated and control groups at P5 (P˂0.01). The cardinal lobes area: anterobasal (P˂0.05), central (P˂0.01), posterior (P˂0.001) and flocculonodular (P˂0.001) present significant differences at P5, whereas anterodorsal lobe at P8 (P˂0.05). Fissures lengths have shown significant differences in secondary and posterolateral fissure at P5 (P˂0.01), preculminal fissure at P8 (P˂0,001). The AT2 receptor blockage affects the cerebellum growth at P5, coincident with the maximum expression of granular cells mitogenic protein (Shh) secreted from Purkinje cells. The data suggest that AT2 receptor could be involved in the mechanisms of cellular proliferation in cerebellum development.