Long-term potentiation in the dentate gyrus in freely moving rats is reinforced by intraventricular application of norepinephrine, but not oxotremorine.
Neurobiol Learn Mem
; 83(1): 72-8, 2005 Jan.
Article
em En
| MEDLINE
| ID: mdl-15607691
Growing evidence suggests that processes of synaptic plasticity, such as long-term potentiation (LTP) occurring in one synaptic population, can be modulated by consolidating afferents from other brain structures. We have previously shown that an early-LTP lasting less than 4 h (E-LTP) in the dentate gyrus can be prolonged by stimulating the basolateral amygdala, the septum or the locus coeruleus within a specific time window. Pharmacological experiments have suggested that noradregeneric (NE) and/or cholinergic systems might be involved in these effects. We have therefore investigated whether the direct intraventricular application of agonists for NE- or muscarinic receptors is able to modulate synaptic plasticity. E-LTP was induced at the dentate gyrus of freely moving rats using a mild tetanization protocol that induces only an E-LTP. NE or oxotremorine (OXO) were applied icv 10 min after the tetanus. Results show that low doses of NE (1.5 and 5 nM) effectively prolong LTP. A higher dose (50 nM) was not effective. None of the OXO doses employed (5, 25, and 50 nM) showed similar effects. These results stress the importance of transmitter-specific modulatory influences on the time course of synaptic plasticity, in particular NE whose application mimics the reinforcing effect of directly stimulating limbic structures on LTP.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oxotremorina
/
Reforço Psicológico
/
Norepinefrina
/
Potenciação de Longa Duração
/
Giro Denteado
Limite:
Animals
Idioma:
En
Revista:
Neurobiol Learn Mem
Assunto da revista:
BIOLOGIA
/
CIENCIAS DO COMPORTAMENTO
/
NEUROLOGIA
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Cuba
País de publicação:
Estados Unidos