Oxytocin excites BNST interneurons and inhibits BNST output neurons to the central amygdala.
Neuropharmacology
; 192: 108601, 2021 07 01.
Article
en En
| MEDLINE
| ID: mdl-33971215
The dorsolateral bed nucleus of the stria terminalis (BNSTDL) has high expression of oxytocin (OT) receptors (OTR), which were shown to facilitate cued fear. However, the role of OTR in the modulation of BNSTDL activity remains elusive. BNSTDL contains GABA-ergic neurons classified based on intrinsic membrane properties into three types. Using in vitro patch-clamp recordings in male rats, we demonstrate that OT selectively excites and increases spontaneous firing rate of Type I BNSTDL neurons. As a consequence, OT increases the frequency, but not amplitude, of spontaneous inhibitory post-synaptic currents (sIPSCs) selectively in Type II neurons, an effect abolished by OTR antagonist or tetrodotoxin, and reduces spontaneous firing rate in these neurons. These results suggest an indirect effect of OT in Type II neurons, which is mediated via OT-induced increase in firing of Type I interneurons. As Type II BNSTDL neurons were shown projecting to the central amygdala (CeA), we also recorded from retrogradely labeled BNSTâCeA neurons and we show that OT increases the frequency of sIPSC in these Type II BNSTâCeA output neurons. In contrast, in Type III neurons, OT reduces the amplitude, but not frequency, of both sIPSCs and evoked IPSCs via a postsynaptic mechanism without changing their intrinsic excitability. We present a model of fine-tuned modulation of BNSTDL activity by OT, which selectively excites BNSTDL interneurons and inhibits Type II BNSTâCeA output neurons. These results suggest that OTR in the BNST might facilitate cued fear by inhibiting the BNSTâCeA neurons.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Núcleos Septales
/
Oxitocina
/
Potenciales Postsinápticos Excitadores
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Potenciales Postsinápticos Inhibidores
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Núcleo Amigdalino Central
/
Interneuronas
Límite:
Animals
Idioma:
En
Revista:
Neuropharmacology
Año:
2021
Tipo del documento:
Article
Pais de publicación:
Reino Unido