INIBIOMA   20415
INSTITUTO DE INVESTIGACIONES EN BIODIVERSIDAD Y MEDIOAMBIENTE
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Broadcasting from adult-born dentate granule cells to the hippocampal circuitry
Autor/es:
SILVIO GABRIEL TEMPRANA; ALEJANDRO F. SCHINDER; LUCAS A. MONGIAT
Lugar:
Huerta Grande, Cordoba
Reunión:
Congreso; Reunión Anual Sociedad Argentina de Investigación en Neurociencias; 2013
Institución organizadora:
Sociedad Argentina de Investigacion en Neurociencias
Resumen:
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The dentate gyrus of adult mammals is a neurogenic
region that continuously generates dentate granule cells (DGCs). New
DGCs migrate, develop and integrate into the circuitry during a
period of 6 to 8 weeks. Recently, we have proved that 4-week-old
(immature) DGCs display low threshold for activation and high
associativity to incoming inputs. Yet, the functional implication of
these findings depends on the ability of immature DGCs to deliver
information onto the target areas, and on the nature of the
transmitted message. We are currently investigating whether immature
DGCs can convey information to the hippocampal network and the nature
of those signals. We combine retroviral transduction of neuronal
progenitors with optogenetics to obtain cohorts of immature DGCs
expressing channelrhodopsin-2 (ChR2). ChR2-DGCs can be activated by
brief pulses of blue light delivered by a laser source. Acute
hippocampal slices containing ChR2-DGCs were prepared and voltage
clamp recordings were performed onto pyramidal neurons in CA3 and
mature DGCs in the granule cell layer to monitor light-evoked
postsynaptic currents (PSCs). In CA3 pyramidal neurons, light
stimulation evoked excitatory and feedforward inhibitory PSCs,
whereas mature DGCs only evidence light-induced feedback inhibition.
Further experiments to establish the contribution of different
cohorts of adult-born DGCs to information processing are currently
underway.