IIBBA   05544
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE BUENOS AIRES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Newly generated neurons convey higher levels of associativity to information processing in the adult dentate gyrus
Autor/es:
MARÍA BELÉN PARDI; LUCAS A. MONGIAT; ALEJANDRO F. SCHINDER ; ANTONIA MARÍN-BURGIN
Lugar:
Florence
Reunión:
Congreso; 8th IBRO World Congress of Neurosciences; 2011
Institución organizadora:
International Brain Research Organization
Resumen:
Adult neurogenesis provides a constant pool of new granule cells (GCs) to the dentate gyrus (DG) of the hippocampus. During maturation, these GCs present higher excitability than mature neurons and require weaker inputs to be recruited in response to activation of afferent inputs. These properties suggest that while mature GCs are presumably more selective in their responses, immature GCs could be recruited by several inputs, allowing associations to occur. To study differences in associativity between mature and immature GCs, we combined imaging and electrophysiological recordings from hippocampal slices obtained from adult mice after retroviral expression of RFP to identify immature GCs. GCs activity was monitored by loading the cells with the calcium dye OGB-AM1. Two electrodes were placed to stimulate independent medial perforant path inputs at different intensities. Under these conditions, the majority of mature granule cells responded to only one of the two stimuli, however most immature cells were equally recruited by both stimuli. This indicates that, while independent inputs tend to recruit different populations of mature neurons, they recruit the same population immature granule cells, suggesting a higher ability of immature neurons to associate independent inputs. The level of associativity in the population of mature cells was incremented by blocking gabaergic inhibition, but not in the population of immature neurons. The increased associativity observed in immature GCs suggests that this population of neurons could serve the DG to produce temporal associations.