TY - JOUR
T1 - Involvement of dopamine D2 receptors in apomorphine-induced facilitation of forebrain serotonin output
AU - Mendlin, Anna
AU - Martín, Francisco J.
AU - Jacobs, Barry L.
PY - 1998/6/26
Y1 - 1998/6/26
N2 - The effect of systemic administration of the nonselective dopamine receptor agonist apomorphine on efflux of serotonin (5-hydroxytryptamine, 5-HT) in striatum and hippocampus of freely moving rats was examined using in vivo microdialysis. 5-HT efflux was increased by a moderate dose of apomorphine sufficient for a postsynaptic dopaminergic effect (0.5 mg/kg, s.c.), but not by a lower dose (0.1 mg/kg, s.c.), that acts preferentially on presynaptic dopamine receptors. This effect was blocked by a dopamine D2 receptor antagonist raclopride, administered either systemically or locally into striatum, but not by a 5-HT(1A) receptor antagonist N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl}-N-(2-pyridinyl) cyclohexanecarboxamide 3HCl (WAY-100635). This indicates that dopamine D2 receptors, and not 5-HT(1A) receptors, mediate the facilitatory effect of apomorphine, and that this effect occurs at the nerve terminal level. Behavioral effects of apomorphine outlasted the concomitant changes in 5-HT efflux, suggesting that these changes resulted from dopaminergic receptor activation, rather than from the drug-induced behavioral arousal. Copyright (C) 1998 Elsevier Science B.V. All rights reserved.
AB - The effect of systemic administration of the nonselective dopamine receptor agonist apomorphine on efflux of serotonin (5-hydroxytryptamine, 5-HT) in striatum and hippocampus of freely moving rats was examined using in vivo microdialysis. 5-HT efflux was increased by a moderate dose of apomorphine sufficient for a postsynaptic dopaminergic effect (0.5 mg/kg, s.c.), but not by a lower dose (0.1 mg/kg, s.c.), that acts preferentially on presynaptic dopamine receptors. This effect was blocked by a dopamine D2 receptor antagonist raclopride, administered either systemically or locally into striatum, but not by a 5-HT(1A) receptor antagonist N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl}-N-(2-pyridinyl) cyclohexanecarboxamide 3HCl (WAY-100635). This indicates that dopamine D2 receptors, and not 5-HT(1A) receptors, mediate the facilitatory effect of apomorphine, and that this effect occurs at the nerve terminal level. Behavioral effects of apomorphine outlasted the concomitant changes in 5-HT efflux, suggesting that these changes resulted from dopaminergic receptor activation, rather than from the drug-induced behavioral arousal. Copyright (C) 1998 Elsevier Science B.V. All rights reserved.
KW - 5-HT (5-hydroxytryptamine, serotonin)
KW - 5-HT(1A) autoreceptor
KW - Dopamine
KW - Dopamine D receptor
KW - Microdialysis
KW - Stereotypy
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U2 - 10.1016/S0014-2999(98)00321-5
DO - 10.1016/S0014-2999(98)00321-5
M3 - Article
C2 - 9721020
AN - SCOPUS:0031595102
VL - 351
SP - 291
EP - 298
JO - European Journal of Pharmacology
JF - European Journal of Pharmacology
SN - 0014-2999
IS - 3
ER -