INIMEC - CONICET   05467
INSTITUTO DE INVESTIGACION MEDICA MERCEDES Y MARTIN FERREYRA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
GABAA RECEPTOR ACTIVATION ARE INVOLVED IN DIFFERENTIATION OF EMBRYONIC HYPOTHALAMIC NEURONS DEPENDING OF SEX
Autor/es:
CAMBIASSO, M.J.; MIR, F.
Lugar:
Huerta Grande Cordoba Argentina
Reunión:
Congreso; XXVII Reunion Anual de la Sociedad Argentina de Insvestigación en Neurociencias (SAN); 2012
Institución organizadora:
SAN
Resumen:
GABA is the main inhibitory neurotransmitter in adult central nervous system;
however during development it exerts trophic actions. The proposed
mechanism for these effects is the activation of GABAA receptor mediated
current, which elicit a depolarization and the opening of voltage-dependent
calcium-channels. This calcium influx acts as a second messenger that
modulates the activity of a variety of kinases. Some kinases, like CAMKII and
p42/44 MAPK are involved in the GABA-induced neurite outgrowth of immature
neurons. Previous results of our lab have demonstrated that hypothalamic
neurons show sex differences in neurite differentiation in response to estradiol.
To assess sex differences in GABA-mediated neuronal differentiation, male and
female hypothalamic cultures were treated with a GABAA receptor agonist
(muscimol 100ìM) or antagonist (bicuculline 100ìM) during 2 DIV. Neurite
outgrowth, soma area, number of neurites and number of neurite ramifications
were quantified by morphometric analysis in five independent cultures.
Muscimol-treated cultures showed neurons with shorter axons than controls
irrespective of sex (p< 0.01); whereas the media longitude of minor processes
was larger in males than females (p< 0.001). The percentage of neurons in
stage II is also increased in muscimol-treated male cultures (muscimol 42% vs.
control 30%). The lack of immunofluorescence staining of Tau-1 protein in such
neurons suggests they are arrested in differentiation.
outgrowth, soma area, number of neurites and number of neurite ramifications
were quantified by morphometric analysis in five independent cultures.
Muscimol-treated cultures showed neurons with shorter axons than controls
irrespective of sex (p< 0.01); whereas the media longitude of minor processes
was larger in males than females (p< 0.001). The percentage of neurons in
stage II is also increased in muscimol-treated male cultures (muscimol 42% vs.
control 30%). The lack of immunofluorescence staining of Tau-1 protein in such
neurons suggests they are arrested in differentiation.
outgrowth, soma area, number of neurites and number of neurite ramifications
were quantified by morphometric analysis in five independent cultures.
Muscimol-treated cultures showed neurons with shorter axons than controls
irrespective of sex (p< 0.01); whereas the media longitude of minor processes
was larger in males than females (p< 0.001). The percentage of neurons in
stage II is also increased in muscimol-treated male cultures (muscimol 42% vs.
control 30%). The lack of immunofluorescence staining of Tau-1 protein in such
neurons suggests they are arrested in differentiation.
ìM) or antagonist (bicuculline 100ìM) during 2 DIV. Neurite
outgrowth, soma area, number of neurites and number of neurite ramifications
were quantified by morphometric analysis in five independent cultures.
Muscimol-treated cultures showed neurons with shorter axons than controls
irrespective of sex (p< 0.01); whereas the media longitude of minor processes
was larger in males than females (p< 0.001). The percentage of neurons in
stage II is also increased in muscimol-treated male cultures (muscimol 42% vs.
control 30%). The lack of immunofluorescence staining of Tau-1 protein in such
neurons suggests they are arrested in differentiation.