Precise spike timing dynamics of hippocampal place cell activity sensitive to cholinergic disruption.
Hippocampus
; 27(10): 1069-1082, 2017 10.
Article
em En
| MEDLINE
| ID: mdl-28628945
ABSTRACT
New memory formation depends on both the hippocampus and modulatory effects of acetylcholine. The mechanism by which acetylcholine levels in the hippocampus enable new encoding remains poorly understood. Here, we tested the hypothesis that cholinergic modulation supports memory formation by leading to structured spike timing in the hippocampus. Specifically, we tested if phase precession in dorsal CA1 was reduced under the influence of a systemic cholinergic antagonist. Unit and field potential were recorded from the dorsal CA1 of rats as they completed laps on a circular track for food rewards before and during the influence of the systemically administered acetylcholine muscarinic receptor antagonist scopolamine. We found that scopolamine significantly reduced phase precession of spiking relative to the field theta, and that this was due to a decrease in the frequency of the spiking rhythmicity. We also found that the correlation between position and theta phase was significantly reduced. This effect was not due to changes in spatial tuning as tuning remained stable for those cells analyzed. Similarly, it was not due to changes in lap-to-lap reliability of spiking onset or offset relative to either position or phase as the reliability did not decrease following scopolamine administration. These findings support the hypothesis that memory impairments that follow muscarinic blockade are the result of degraded spike timing in the hippocampus.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Escopolamina
/
Potenciais de Ação
/
Acetilcolina
/
Antagonistas Colinérgicos
/
Região CA1 Hipocampal
/
Células de Lugar
Tipo de estudo:
Diagnostic_studies
Limite:
Animals
Idioma:
En
Revista:
Hippocampus
Assunto da revista:
CEREBRO
Ano de publicação:
2017
Tipo de documento:
Article