S 15535: a highly selective benzodioxopiperazine 5-HT1A receptor ligand which acts as an agonist and an antagonist at presynaptic and postsynaptic sites respectively.
The novel benzodioxopiperazine, S 15535 (4-(benzodioxan-5-yl)1-(indan-2- yl)piperazine), displayed high affinity for 5-HT1A binding sites (1.8 nM) whereas its affinity was 100-fold lower at other 5-HT receptor types, at alpha 1, alpha 2- and beta-adrenoceptors and at dopamine D1 and D2 receptors. In vivo, S 15535 (0.16-10 mg/kg s.c.) acted as an antagonist at postsynaptic 5-HT1A receptors in completely blocking the flat-body posture and hypothermia elicited by the 5-HT1A receptor agonist, 8-OH-DPAT. It had no effect when applied alone. At presynaptic 5-HT1A receptors, S 15535 acted as an agonist in inhibiting striatal accumulation of 5-hydroxytryptophan (0.04-0.63 mg/kg s.c.) and in spiperone reversibly reducing electrical activity of the dorsal raphe nucleus (0.004-0.031 mg/kg i.v.). At doses up to 40.0 mg/kg s.c., S 15535 neither inhibited methylphenidate-induced gnawing nor elicited ptosis suggesting a lack of antagonist properties at, respectively, dopamine D2 receptors and alpha 1-adrenoceptors. In conclusion, S 15535 is a potent 5-HT1A ligand which acts, in vivo, as a highly selective agonist and antagonist at presynaptic and postsynaptic 5-HT1A receptors, respectively.
Millan
M J
MJ
Institut de Recherches Servier (I.D.R.S.), Puteaux, France.
Rivet
J M
JM
Canton
H
H
Lejeune
F
F
Gobert
A
A
Widdowson
P
P
Bervoets
K
K
Brocco
M
M
Peglion
J L
JL
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001763:Blepharoptosis / Q000139:chemically induced; D001831:Body Temperature / Q000187:drug effects; D001923:Brain Chemistry / Q000187:drug effects; D008024:Ligands; D008297:Male; D010879:Piperazines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects; D017448:Receptors, Dopamine D2 / Q000187:drug effects; D011985:Receptors, Serotonin / Q000187:drug effects*; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*; D013569:Synapses / Q000187:drug effects*
D008024:Ligands; D010879:Piperazines; D011942:Receptors, Adrenergic, alpha; D017448:Receptors, Dopamine D2; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; C058895:1-(2-methoxyphenyl)-4-(4-(2-phthalimido)butyl)piperazine; C079549:4-(benzodioxan-5-yl)-1-(indan-2-yl)piperazine; C053428:BMY 7378