Central serotonin4 receptors selectively regulate the impulse-dependent exocytosis of dopamine in the rat striatum: in vivo studies with morphine, amphetamine and cocaine.
Neuropharmacology
; 43(7): 1099-109, 2002 Dec.
Article
en En
| MEDLINE
| ID: mdl-12504916
ABSTRACT
In vivo microdialysis and single-cell extracellular recordings were used to assess the involvement of serotonin(4) (5-HT(4)) receptors in the effects induced by morphine, amphetamine and cocaine on nigrostriatal and mesoaccumbal dopaminergic (DA) pathway activity. The increase in striatal DA release induced by morphine (2.5 mg/kg, s.c.) was significantly reduced by the selective 5-HT(4) antagonists GR 125487 (0.1 and 1 mg/kg, i.p.) or SB 204070 (1 mg/kg, i.p.), and potentiated by the 5-HT(4) agonist prucalopride (5 mg/kg, i.p.). Neither of these compounds affected morphine-stimulated DA release in the nucleus accumbens. In both regions, amphetamine (2 mg/kg, i.p.) and cocaine (15 mg/kg, i.p.) induced DA release was affected neither by GR 125487 nor by prucalopride. None of the 5-HT agents used modified basal DA release in either brain region. Finally, GR 125487 (445 microg/kg, i.v.), whilst not affecting basal firing of DA neurons within either the substantia nigra pars compacta nor the ventral tegmental area, significantly reduced morphine (0.1-10 mg/kg, i.v.) stimulated firing of nigrostriatal DA neurons only. These results confirm that 5-HT(4) receptors exert a state-dependent facilitatory control restricted to the nigrostriatal DA pathway, and indicate that 5-HT(4) receptors selectively modulate DA exocytosis associated with increased DA neuron firing rate.
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Bases de datos:
MEDLINE
Asunto principal:
Dopamina
/
Receptores de Serotonina
/
Cocaína
/
Cuerpo Estriado
/
Anfetamina
/
Morfina
Límite:
Animals
Idioma:
En
Revista:
Neuropharmacology
Año:
2002
Tipo del documento:
Article
País de afiliación:
Francia