Presynaptic modulation by group III metabotropic glutamate receptors (mGluRs) of the excitatory postsynaptic potential mediated by mGluR1 in rat cerebellar Purkinje cells.
Neurosci Lett
; 310(1): 61-5, 2001 Sep 07.
Article
en En
| MEDLINE
| ID: mdl-11524158
ABSTRACT
Purkinje neurons were recorded from rat cerebellar slices. Parallel fibres stimulation elicited a fast excitatory postsynaptic potential (EPSP) mediated by ionotropic glutamate (iGluR) -amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors followed by the inhibitory gamma-aminobutyric acidA (GABAA)-dependent postsynaptic potential. In the presence of antagonists for iGluRs and for GABAA receptors, brief tetanic activation evoked a slow metabotropic glutamate receptor (mGluR)-dependent EPSP (mGluR-EPSP). This mGluR-EPSP was blocked by the selective mGluR1 antagonists LY367385 and CPCCOEt, but not by the mGluR5 antagonist MPEP. Group II agonists affected neither iGluR-EPSP nor mGluR-EPSP. Conversely, L-AP4 and L-SOP, group III mGluR agonists, inhibited both iGluR- and mGluR-EPSPs. The depolarisations evoked by both AMPA and group I agonists were unaffected, indicating a presynaptic action of group III mGluRs. These data suggest that glutamate released by parallel fibres activates group III mGluR autoreceptors, depressing both iGluR- and mGluR1-mediated EPSPs.
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Bases de datos:
MEDLINE
Asunto principal:
Células de Purkinje
/
Benzoatos
/
Cerebelo
/
Receptores Presinapticos
/
Receptores de Glutamato Metabotrópico
/
Potenciales Postsinápticos Excitadores
Límite:
Animals
Idioma:
En
Revista:
Neurosci Lett
Año:
2001
Tipo del documento:
Article
País de afiliación:
Italia