α2-adrenoceptor mediated inhibition of [3H]dopamine release from nucleus accumbens slices and monoamine levels in a rat model for attention- deficit hyperactivity disorder

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dc.contributor.authorDe Villiers A.S.
dc.contributor.authorRussell V.A.
dc.contributor.authorSagvolden T.
dc.contributor.authorSearson A.
dc.contributor.authorJaffer A.
dc.contributor.authorTaljaard J.J.F.
dc.contributor.authorDe Villiers A.S.
dc.contributor.authorRussell V.A.
dc.contributor.authorSagvolden T.
dc.contributor.authorSearson A.
dc.contributor.authorJaffer A.
dc.contributor.authorTaljaard J.J.F.
dc.date.accessioned2011-05-15T16:17:26Z
dc.date.accessioned2011-05-15T16:17:26Z
dc.date.available2011-05-15T16:17:26Z
dc.date.available2011-05-15T16:17:26Z
dc.date.issued1995
dc.date.issued1995
dc.description.abstractThe spontaneously hypertensive rat (SHR) has been proposed as an animal model for attention-deficit hyperactivity disorder (ADHD). The behavioural problems have been suggested to be secondary to altered reinforcement mechanisms in which nucleus accumbens dopaminergic activity plays an important role. Interaction between the noradrenergic and dopaminergic system in the nucleus accumbens has been implicated in the locomotor hyperactivity and impaired discriminative performance of SHR. The present study therefore investigated whether there was any change in the α2-adrenoceptor mediated inhibition of dopamine release from nucleus accumbens slices of SHR in comparison with their normotensive Wistar-Kyoto (WKY) controls. The electrically stimulated release of [3H]dopamine (DA) from nucleus accumbens slices was decreased to a similar extent by UK14,304, an α2-adrenoceptor agonist, in SHR and WKY. Basal norepinephrine (NE) levels were increased in locus coeruleus (LC) and A2 noradrenergic nuclei, but not in the A1 nucleus of SHR, while basal serotonin (5-HT) levels were increased in all these pons- medulla nuclei. These results suggest that a primarily dysfunctional LC and A2 nucleus does not have a secondary effect on dopaminergic transmission in the nucleus accumbens via α2-adrenoceptor mediated inhibition of DA release. Basal monoamine levels in several brain areas of SHR were significantly different from that of WKY. DA, and 5-HT turnover were decreased in SHR versus WKY suggesting hypofunctional dopaminergic and serotonergic systems in some brain areas of SHR.
dc.description.abstractThe spontaneously hypertensive rat (SHR) has been proposed as an animal model for attention-deficit hyperactivity disorder (ADHD). The behavioural problems have been suggested to be secondary to altered reinforcement mechanisms in which nucleus accumbens dopaminergic activity plays an important role. Interaction between the noradrenergic and dopaminergic system in the nucleus accumbens has been implicated in the locomotor hyperactivity and impaired discriminative performance of SHR. The present study therefore investigated whether there was any change in the α2-adrenoceptor mediated inhibition of dopamine release from nucleus accumbens slices of SHR in comparison with their normotensive Wistar-Kyoto (WKY) controls. The electrically stimulated release of [3H]dopamine (DA) from nucleus accumbens slices was decreased to a similar extent by UK14,304, an α2-adrenoceptor agonist, in SHR and WKY. Basal norepinephrine (NE) levels were increased in locus coeruleus (LC) and A2 noradrenergic nuclei, but not in the A1 nucleus of SHR, while basal serotonin (5-HT) levels were increased in all these pons- medulla nuclei. These results suggest that a primarily dysfunctional LC and A2 nucleus does not have a secondary effect on dopaminergic transmission in the nucleus accumbens via α2-adrenoceptor mediated inhibition of DA release. Basal monoamine levels in several brain areas of SHR were significantly different from that of WKY. DA, and 5-HT turnover were decreased in SHR versus WKY suggesting hypofunctional dopaminergic and serotonergic systems in some brain areas of SHR.
dc.description.versionArticle
dc.description.versionArticle
dc.identifier.citationNeurochemical Research
dc.identifier.citation20
dc.identifier.citation4
dc.identifier.citationNeurochemical Research
dc.identifier.citation20
dc.identifier.citation4
dc.identifier.issn03643190
dc.identifier.issn03643190
dc.identifier.urihttp://hdl.handle.net/10019.1/14212
dc.identifier.urihttp://hdl.handle.net/10019.1/14212
dc.subjectalpha 2 adrenergic receptor; brimonidine; citalopram; desipramine; dopamine; homovanillic acid; monoamine; noradrenalin; serotonin; 5 hydroxyindoleacetic acid brain level; animal model; animal tissue; article; brain slice; controlled study; dopamine brain level; dopamine release; dopaminergic system; hyperactivity; locus ceruleus; male; minimal brain dysfunction; monoamine release; nonhuman; noradrenalin brain level; nucleus accumbens; priority journal; rat; serotonin brain level; substantia nigra; ventral tegmentum; Animal; Antihypertensive Agents; Attention Deficit Disorder with Hyperactivity; Biogenic Monoamines; Disease Models, Animal; Dopamine; Hypertension; In Vitro; Male; Neurons; Norepinephrine; Nucleus Accumbens; Quinoxalines; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Receptors, Adrenergic, alpha-2; Support, Non-U.S. Gov't; Tritium
dc.subjectalpha 2 adrenergic receptor
dc.subjectbrimonidine
dc.subjectcitalopram
dc.subjectdesipramine
dc.subjectdopamine
dc.subjecthomovanillic acid
dc.subjectmonoamine
dc.subjectnoradrenalin
dc.subjectserotonin
dc.subject5 hydroxyindoleacetic acid brain level
dc.subjectanimal model
dc.subjectanimal tissue
dc.subjectarticle
dc.subjectbrain slice
dc.subjectcontrolled study
dc.subjectdopamine brain level
dc.subjectdopamine release
dc.subjectdopaminergic system
dc.subjecthyperactivity
dc.subjectlocus ceruleus
dc.subjectmale
dc.subjectminimal brain dysfunction
dc.subjectmonoamine release
dc.subjectnonhuman
dc.subjectnoradrenalin brain level
dc.subjectnucleus accumbens
dc.subjectpriority journal
dc.subjectrat
dc.subjectserotonin brain level
dc.subjectsubstantia nigra
dc.subjectventral tegmentum
dc.subjectAnimal
dc.subjectAntihypertensive Agents
dc.subjectAttention Deficit Disorder with Hyperactivity
dc.subjectBiogenic Monoamines
dc.subjectDisease Models, Animal
dc.subjectDopamine
dc.subjectHypertension
dc.subjectIn Vitro
dc.subjectMale
dc.subjectNeurons
dc.subjectNorepinephrine
dc.subjectNucleus Accumbens
dc.subjectQuinoxalines
dc.subjectRats
dc.subjectRats, Inbred SHR
dc.subjectRats, Inbred WKY
dc.subjectReceptors, Adrenergic, alpha-2
dc.subjectSupport, Non-U.S. Gov't
dc.subjectTritium
dc.titleα2-adrenoceptor mediated inhibition of [3H]dopamine release from nucleus accumbens slices and monoamine levels in a rat model for attention- deficit hyperactivity disorder
dc.titleα2-adrenoceptor mediated inhibition of [3H]dopamine release from nucleus accumbens slices and monoamine levels in a rat model for attention- deficit hyperactivity disorder
dc.typeArticle
dc.typeArticle
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