Interactions of selective serotonin reuptake inhibitors with the serotonin 5-HT2c receptor.

Article Details

Citation

Palvimaki EP, Roth BL, Majasuo H, Laakso A, Kuoppamaki M, Syvalahti E, Hietala J

Interactions of selective serotonin reuptake inhibitors with the serotonin 5-HT2c receptor.

Psychopharmacology (Berl). 1996 Aug;126(3):234-40.

PubMed ID
8876023 [ View in PubMed
]
Abstract

Interactions of the selective serotonin reuptake inhibitors (SSRIs) citalopram, fluoxetine and its main metabolite norfluoxetine, and the tricyclic antidepressant (TCA) imipramine with the rat serotonin 5-HT2C receptor in a clonal cell line and in the rat choroid plexus were investigated by radioligand binding and phosphoinositide (PI) hydrolysis assays. For comparison, the affinities of a variety of other antidepressants of different chemical classes for the cloned rat 5-HT2C and 5-HT2A receptors were also determined by radioligand binding assays. Fluoxetine displayed relatively high affinity for the 5-HT2C receptor in the choroid plexus, with a Ki value for inhibition of [3H]mesulergine binding of 55.4 nM. The Ki values for imipramine, norfluoxetine and citalopram were 136 nM, 203 nM, and 298 nM, respectively. Similar rank order of potency was detected in PI hydrolysis assays, which showed that these drugs are antagonists at the 5-HT2C receptor without exhibiting inverse agonist activity. [3H]Ketanserin (5-HT2A) binding assays revealed that the SSRIs fluoxetine, norfluoxetine and citalopram show 10- to 23-fold selectivity for the 5-HT2C receptor in vitro, whereas the TCA imipramine does not. Many other TCAs also had high to intermediate affinity for both 5-HT2A and 5-HT2C receptors. The present data provide evidence that fluoxetine, norfluoxetine and citalopram, along with many other antidepressant compounds, interact directly with the 5-HT2C receptor.

DrugBank Data that Cites this Article

Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
Amitriptyline5-hydroxytryptamine receptor 2CProteinHumans
Unknown
Antagonist
Details
Amoxapine5-hydroxytryptamine receptor 2AProteinHumans
Unknown
Antagonist
Details
Desipramine5-hydroxytryptamine receptor 2CProteinHumans
Unknown
Binder
Details
Imipramine5-hydroxytryptamine receptor 2CProteinHumans
Unknown
Antagonist
Binder
Details
Nortriptyline5-hydroxytryptamine receptor 2CProteinHumans
Unknown
Antagonist
Downregulator
Details