Effect of repeated treatment with mirtazapine on the central alpha1-adrenergic receptors.

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Citation

Rogoz Z, Wrobel A, Dlaboga D, Maj J, Dziedzicka-Wasylewska M

Effect of repeated treatment with mirtazapine on the central alpha1-adrenergic receptors.

J Physiol Pharmacol. 2002 Mar;53(1):105-16.

PubMed ID
11939713 [ View in PubMed
]
Abstract

Mirtazapine (MIR) is an antidepressant which enhances noradrenergic and serotonergic 5-HT1A neurotransmission via antagomism of central alpha2-adrenergic autoreceptors and heteroreceptors. The drugs does not inhibit noradrenaline and serotonin reuptake but blocks the 5-HT, and 5-HT3 receptors and has high affinity only for central and peripheral histamine H1 receptors. The present study was aimed at determining whether repeated MIR treatment induced adaptive changes in the alpha1-adrenergic receptors, similar to those reported by us early for tricyclic antidepressants, The experiments were carried out on male mice and rats. MIR was administered at a dose of 10 mg/kg once or repeatedly (twice daily for 14 days). The obtained results showed that MIR administrated repeatedly potentiated the methoxamine- induced exploratory hyperactivity in rats and clonidine-induced aggressiveness in mice, those effects being mediated by alpha1-adrenergic receptors. MIR given repeatedly (but not acutely) increased the binding (Bmax ) of [3H]prazosin to alpha1-adrenergic receptors in cerebral cortex, however, the ability of the alpha1-adrenoceptor agonist phenylephrine to compete for the these sites was not significantly changed. The above results indicate that repeated MIR administration increases the responsiveness of alpha1-adrenergic system (behavioural and biochemical changes), as tricyclics do. However, the question whether the increased functional responsiveness found in the present study is important for the clinical antidepressant efficacy, remains open.

DrugBank Data that Cites this Article

Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
Mirtazapine5HT3 serotonin receptorProteinHumans
Yes
Antagonist
Details