ROLE OF CB1R IN HIPPOCAMPAL DENDRITIC ARBORIZATION

CALTANA, LAURA ROMINA; SANCHEZ, VIVIANA; SORIANO, DELIA; VILLALBA, NERINA; NOVAK, LUCIANA; MADARNAS, CATALINA; BRUSCO, ALICIA

Congreso; XXXII CONGRESO ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACION EN NEUROCIENCIAS; 2017

Endocannabinoid system (eCBs) regulates neurogenic processes (neuronal proliferation, specification and maturation). Cannabinoid receptor Type 1 (CB1R) is expressed in the progenitor cells of the subventricular zone and dentate gyrus (DG) in adult brain. In addition, intermediate progenitor cells are also targeted by eCBs. eCBs is involved in physiological processes such as memory, learning, motor coordination, anxiety and mood. CB1R deficient mice (CB1 - / -) is a genetic model of depression since it deregulates the serotoninergic system, producing mood alterations.The aim of this work was to evaluate the effect of genetic ablation of CB1R in hippocampal neuronal morphology in vitro and in vivo.Neuronal morphology was studied by MAP2 immnostaining in hippocampal area CA1 from CB1 - / - and their respective wild type (CB1 + / +) at postnatal day 0, and in primary cultures of hippocampal neurons of postnatal day 0, after 7 days of culture.In vitro observation shows that CB1-/- present a higher number of primary dendrites than CB1+/+, with a shorter length.In vivo the number of nucleus per area in pyramidal layer is lower in CB1 -/- mice as well as the relative area of dendritic profiles in the corresponding stratum radiatum. This result is in accord with the in vitro result. Conclusion: CB1R is implicated in the development of dendritic arborization of hippocampal neurons.