Modulation of serotonergic function in rat brain by VN2222, a serotonin reuptake inhibitor and 5-HT1A receptor agonist.
VN2222 (1-(benzo[b]thiophen-3-yl)-3-[4-(2-methoxiphenyl piperazin-1-yl]propan-1-ol) is a potential antidepressant with high affinity for the serotonin transporter and 5-HT(1A) receptors. Locally applied, VN2222 enhanced the extracellular 5-hydroxytryptamine (5-HT) concentration (5-HT(ext)) in rat striatum to 780% of baseline whereas its systemic administration (1-10 mg/kg s.c.) reduced 5-HT(ext). In the presence of citalopram, 8-OH-DPAT or VN2222 applied in medial prefrontal cortex reduced 5-HT(ext). Fluoxetine, VN2222, and 8-OH-DPAT suppressed the firing rate of dorsal raphe 5-HT neurons (ED(50): 790, 14.9, and 0.8 microg/kg i.v., respectively). These effects were antagonized by WAY 100635. Administration of VN2222 for 2 weeks desensitized 5-HT(1A) receptors as assessed by microdialysis and single-unit recordings (ED(50) values for 8-OH-DPAT were 0.45 and 2.34 microg/kg i.v. for controls and rats treated with 6 mg/kg day VN2222). These results show that VN2222 is a mixed 5-HT reuptake inhibitor/5-HT(1A) agonist that markedly desensitizes 5-HT(1A) autoreceptors. These properties suggest that it may be a clinically effective dual action antidepressant drug.
Romero
Luz
L
Department of Neurochemistry, Institut d'Investigacions Biomèdiques de Barcelona, CSIC (IDIBAPS), Barcelona, Spain.
Celada
Pau
P
Martín-Ruiz
Raúl
R
Díaz-Mataix
Llorenç
L
Mourelle
Marisabel
M
Delgadillo
Joaquim
J
Hervás
Ildefonso
I
Artigas
Francesc
F
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D008297:Male; D010879:Piperazines / Q000737:chemistry / Q000494:pharmacology*; D020005:Propanols / Q000737:chemistry / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D011985:Receptors, Serotonin / Q000378:metabolism*; D044263:Receptors, Serotonin, 5-HT1; D012701:Serotonin / Q000378:metabolism*; D017366:Serotonin Receptor Agonists / Q000737:chemistry / Q000494:pharmacology*; D017367:Selective Serotonin Reuptake Inhibitors / Q000737:chemistry / Q000494:pharmacology*
D010879:Piperazines; D020005:Propanols; D011985:Receptors, Serotonin; D044263:Receptors, Serotonin, 5-HT1; D012701:Serotonin; D017366:Serotonin Receptor Agonists; D017367:Selective Serotonin Reuptake Inhibitors; C466061:VN2222