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7938832 
Journal Article 
Mirtazapine increases dopamine release in prefrontal cortex by 5-HT1A receptor activation 
Nakayama, K; Sakurai, T; Katsu, H 
2004 
Yes 
Brain Research Bulletin
ISSN: 0361-9230
EISSN: 1873-2747 
63 
3 
237-241 
English 
15145142 
WOS:000221737200005 
Mirtazapine has a low affinity for 5-HT(1A) receptors but shows 5-HT(1A)-agonistic-like effects in behavioral pharmacology test. However, there is to date no clear evidence that mirtazapine enhances 5-HT(1A) neurotransmission. The object of the present study was to assess the effects of mirtazapine on dialysate levels of dopamine and 5-HT in the medial frontal cortex of freely moving rats and to determine whether this drug could modulate 5-HT(1A) neurotransmission. In vivo microdialysis was used to study the effects of mirtazapine on extracellular dopamine and 5-HT levels, and the effect of the 5-HT(1A) antagonist WAY100,356 on extracellular dopamine level increased by mirtazapine in the rat prefrontal cortex. Mirtazapine (4-16 mg/kg, i.p.) produced a dose-dependent increase in extracellular dopamine levels in the medial prefrontal cortex (mPFC) of freely moving rats without modifying those of 5-HT. In the presence of the selective 5-HT(1A) receptor antagonist N-[2-[4-(2-methoxyphenyl)-1-piperazineyl]ethyl]-N-(pyridinyl)-cyclohexane-carboxamide (WAY100,635; 0.3 mg/kg; i.p.), the influence of mirtazapine on cortical levels of dopamine was markedly attenuated. These results indicate that mirtazapine induces the enhancement of the output of cortical dopamine mediated via blockade of alpha(2)-adrenergic receptors and facilitation of post-synaptic 5-HT(1A) function. 
5-HT1A agonist; Dopamine; Microdialysis; Mirtazapine; Prefrontal cortex; Serotonin