Agonist and antagonist actions of yohimbine as compared to fluparoxan at α2‐adrenergic receptors (AR)s, serotonin (5‐HT)1A, 5‐HT1B, 5‐HT1D and dopamine D2 and D3 receptors. Significance for the modulation of frontocortical monoaminergic transmission and depressive states

@article{Millan2000AgonistAA,
  title={Agonist and antagonist actions of yohimbine as compared to fluparoxan at $\alpha$2‐adrenergic receptors (AR)s, serotonin (5‐HT)1A, 5‐HT1B, 5‐HT1D and dopamine D2 and D3 receptors. Significance for the modulation of frontocortical monoaminergic transmission and depressive states},
  author={Mark J Millan and Adrian Newman-Tancredi and Valérie Audinot and Didier Cussac and Françoise Lejeune and Jean Paul Nicolas and Francis Cogé and Jean Pierre Galizzi and Jean A. Boutin and Jean Michel Rivet and Anne Dekeyne and Alain P. Gobert},
  journal={Synapse},
  year={2000},
  volume={35}
}
Herein, we evaluate the interaction of the α2‐AR antagonist, yohimbine, as compared to fluparoxan, at multiple monoaminergic receptors and examine their roles in the modulation of adrenergic, dopaminergic and serotonergic transmission in freely‐moving rats. Yohimbine displays marked affinity at human (h)α2A‐, hα2B‐ and hα2C‐ARs, significant affinity for h5‐HT1A, h5‐HT1B, h5‐HT1D, and hD2 receptors and weak affinity for hD3 receptors. In [35S]GTPγS binding protocols, yohimbine exerts antagonist… 

Mirtazapine enhances frontocortical dopaminergic and corticolimbic adrenergic, but not serotonergic, transmission by blockade of α2‐adrenergic and serotonin2C receptors: a comparison with citalopram

In contrast to citalopram, mirtazapine reinforces frontocortical dopaminergic and corticolimbic adrenergic, but not serotonergic, transmission, and reflects antagonist properties at α2A‐AR and 5‐HT2C receptors.

Anticataleptic properties of α2 adrenergic antagonists in the crossed leg position and bar tests: differential mediation by 5-HT1A receptor activation

Serotonin 5-HT1A receptors play a prominent role in anticataleptic effects of certain α2 adrenergic antagonists in the CLP test, whereas α2-adrenergic mechanisms are likely to be primarily responsible for the anticatalesptic effects of these ligands in the bar test.

Discriminative stimulus properties of idazoxan: mediation by both α2 adrenoceptor antagonism and 5‐HT1A receptor agonism

Both α2 adrenoceptor antagonism and 5‐HT1A receptor agonism appear to contribute to the discriminative stimulus effects of idazoxan, and the role of 5‐ HT1A receptors agonism should be considered when evaluating the behavioral effects of idazxan.

Evaluation of the effects of α2 adrenoceptor antagonism with the D2 receptor antagonist raclopride on conditioned avoidance responding in rats

To the extent that 5-HT1A receptor antagonism failed to block the effects of idazoxan in combination with raclopride on CAR, α2 adrenoceptor antagonism alone appears to potentiate the putative antipsychotic effects produced through D2 receptors antagonism.

The α2-adrenoceptor antagonist atipamezole potentiates anti-Parkinsonian effects and can reduce the adverse cardiovascular effects of dopaminergic drugs in rats

Atipamezole improved the efficacy of L-DOPA and apomorphine in an animal model of Parkinson’s disease and also reduced adverse dopaminergic effects on vigilance and on cardiovascular function, suggesting that an investigation of the effects of specific α2-adrenoceptor antagonists in Parkinson's disease patients is warranted.

The role of α1- and α2-adrenoceptor subtypes in the vasopressor responses induced by dihydroergotamine in ritanserin-pretreated pithed rats

The results suggest that the DHE-induced vasopressor responses in ritanserin-pretreated pithed rats are mediated by α1- ( probably α1A, α1B and α1D) and α2- (probably α2A,α2B andα2C) adrenoceptors and may lead to the development of more selective antimigraine drugs devoid vascular side effects.

Yohimbine is a 5-HT1A agonist in rats in doses exceeding 1mg/kg.

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