Presynaptic alpha-7 nicotinic acetylcholine receptors modulate excitatory synaptic transmission in hippocampal neurons / 生理学报
Acta Physiologica Sinica
; (6): 731-735, 2003.
Article
em En
| WPRIM
| ID: wpr-290900
Biblioteca responsável:
WPRO
ABSTRACT
The effects of presynaptic nicotinic acetylcholine receptors (nAChRs) on excitatory synaptic transmission in CA1 pyramidal neurons of the rat hippocampus were examined by blind whole-cell patch clamp recording from hippocampal slice preparations. Local application of the nAChRs agonist dimethylphenyl-piperazinium iodide (DMPP) did not induce a postsynaptic current response in CA1 pyramidal cells. However, DMPP enhanced the frequency and amplitude of spontaneous excitatory postsynaptic current (sEPSC) in these cells in a dose-dependent manner. This enhancement was blocked by the selective nicotinic alpha-7 receptor antagonist alpha-bungarotoxin, but not by the antagonist mecamylamine, hexamethonium or dihydro-beta-erythroidine. The frequency of miniature excitatory postsynaptic current (mEPSC) in CA1 pyramidal neurons was also increased by application of DMPP, indicating a presynaptic site of action of the agonist. Taken together, these results suggest that activation of presynaptic nAChRs in CA1 pyramidal neurons, which contain alpha-7 subunits, potentiates presynaptic glutamate release and consequently modulate excitatory synaptic transmission in the hippocampus.
Texto completo:
1
Índice:
WPRIM
Assunto principal:
Marca-Passo Artificial
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Farmacologia
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Fisiologia
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Sinapses
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Bungarotoxinas
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Receptores Nicotínicos
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Ratos Wistar
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Receptores Pré-Sinápticos
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Transmissão Sináptica
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Técnicas de Patch-Clamp
Limite:
Animals
Idioma:
En
Revista:
Acta Physiologica Sinica
Ano de publicação:
2003
Tipo de documento:
Article