IIBBA   05544
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE BUENOS AIRES
Unidad Ejecutora - UE
artículos
Título:
Similar GABAergic Inputs in Dentate Granule Cells Born During Embryonic and Adult Neurogenesis
Autor/es:
DIEGO A. LAPLAGNE; JUAN KAMIENKOWSKI; M. SOLEDAD ESPÓSITO; VERÓNICA C. PIATTI; CHUNMEI ZHAO; FRED H. GAGE; ALEJANDRO F. SCHINDER
Revista:
EUROPEAN JOURNAL OF NEUROSCIENCE
Referencias:
Año: 2007 vol. 25 p. 2973 - 2981
ISSN:
0953-816X
Resumen:
Neurogenesis in the dentate gyrus of the hippocampus follows a unique temporal pattern that begins during embryonic development,
peaks during the early postnatal stages and persists through adult life. We have recently shown that dentate granule cells born in
early postnatal and adult mice acquire a remarkably similar afferent connectivity and firing behavior, suggesting that they constitute a
homogeneous functional population [Laplagne et al. (2006) PLoS Biol., 4, e409]. Here we extend our previous study by comparing
mature neurons born in the embryonic and adult hippocampus, with a focus on intrinsic membrane properties and c-aminobutyric acid
(GABA)ergic synaptic inputs. For this purpose, dividing neuroblasts of the ventricular wall were retrovirally labeled with green
fluorescent protein at embryonic day 15 (E15), and progenitor cells of the subgranular zone were labeled with red fluorescent protein
in the same mice at postnatal day 42 (P42, adulthood). Electrophysiological properties of mature neurons born at either stage were
then compared in the same brain slices. Evoked and spontaneous GABAergic postsynaptic responses of perisomatic and dendritic
origin displayed similar characteristics in both neuronal populations. Miniature GABAergic inputs also showed similar functional
properties and pharmacological profile. A comparative analysis of the present data with our previous observations rendered no
significant differences among GABAergic inputs recorded from neurons born in the embryonic, early postnatal and adult mice. Yet,
embryo-born neurons showed a reduced membrane excitability, suggesting a lower engagement in network activity. Our results
demonstrate that granule cells of different age, location and degree of excitability receive GABAergic inputs of equivalent functional
characteristics.et al. (2006) PLoS Biol., 4, e409]. Here we extend our previous study by comparing
mature neurons born in the embryonic and adult hippocampus, with a focus on intrinsic membrane properties and c-aminobutyric acid
(GABA)ergic synaptic inputs. For this purpose, dividing neuroblasts of the ventricular wall were retrovirally labeled with green
fluorescent protein at embryonic day 15 (E15), and progenitor cells of the subgranular zone were labeled with red fluorescent protein
in the same mice at postnatal day 42 (P42, adulthood). Electrophysiological properties of mature neurons born at either stage were
then compared in the same brain slices. Evoked and spontaneous GABAergic postsynaptic responses of perisomatic and dendritic
origin displayed similar characteristics in both neuronal populations. Miniature GABAergic inputs also showed similar functional
properties and pharmacological profile. A comparative analysis of the present data with our previous observations rendered no
significant differences among GABAergic inputs recorded from neurons born in the embryonic, early postnatal and adult mice. Yet,
embryo-born neurons showed a reduced membrane excitability, suggesting a lower engagement in network activity. Our results
demonstrate that granule cells of different age, location and degree of excitability receive GABAergic inputs of equivalent functional
characteristics.c-aminobutyric acid
(GABA)ergic synaptic inputs. For this purpose, dividing neuroblasts of the ventricular wall were retrovirally labeled with green
fluorescent protein at embryonic day 15 (E15), and progenitor cells of the subgranular zone were labeled with red fluorescent protein
in the same mice at postnatal day 42 (P42, adulthood). Electrophysiological properties of mature neurons born at either stage were
then compared in the same brain slices. Evoked and spontaneous GABAergic postsynaptic responses of perisomatic and dendritic
origin displayed similar characteristics in both neuronal populations. Miniature GABAergic inputs also showed similar functional
properties and pharmacological profile. A comparative analysis of the present data with our previous observations rendered no
significant differences among GABAergic inputs recorded from neurons born in the embryonic, early postnatal and adult mice. Yet,
embryo-born neurons showed a reduced membrane excitability, suggesting a lower engagement in network activity. Our results
demonstrate that granule cells of different age, location and degree of excitability receive GABAergic inputs of equivalent functional
characteristics.