Summary
The tritiated derivative of the potent 5-HT1A receptor agonist S-14506 {1[2-(4-fluorobenzoylamino)ethyl]-4-(7-methoxynaphtyl)piperazine} was tested for its capacity to selectively label the serotonin 5-HT1A receptors both in vitro in the rat and the mouse brain, and in vivo in the mouse. In vitro studies showed that the pharmacological profile and the distribution of [3H]S-14506 specific binding sites (Kd=0.15 nM) in different brain regions matched perfectly those of the prototypical 5-HT1A receptor ligand [3H]8-OH-DPAT. However, in the three regions examined (hippocampus, septum, cerebral cortex), the density of [3H]S-14506 specific binding sites was significantly higher (+ 66–90%) than that found with [3H]8-OH-DPAT. Whereas the specific binding of [3H]8-OH-DPAT was markedly reduced by GTP and Gpp(NH)p and increased by Mn2+, that of [3H]S-14506 was essentially unaffected by these compounds. In addition, the alkylating agent N-ethylmaleimide was much less potent to inhibit the specific binding of [3H]S-14506 than that of [3H]8-OH-DPAT. Measurement of in vivo accumulation of tritium one hour after i.v. injection of [3H]S-14506 to mice revealed marked regional differences, with about 2.5 times more radioactivity in the hippocampus than in the cerebellum. Pretreatment with 5-HT1A receptor ligands prevented tritium accumulation in the hippocampus but not in the cerebellum. Autoradiograms from brain sections of injected mice confirmed the specific in vivo labeling of 5-HT1A receptors by [3H]S-14506, therefore suggesting further developments with derivatives of this molecule for positron emission tomography in vivo in man.
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References
Barlow RB (1983) Biodata handling with microcomputers. Elsevier Biosoft, Cambridge
Cheng YC, Prusoff WH (1973) Relationship between the inhibition constant (Ki) and the concentration of inhibitor which causes 50 percent inhibition (IC50) of an enzymatic reaction. Biochem Pharmacol 22: 3099–3108
Colpaert FC, Koek W, Lehmann J, Rivet JM, Lejeune F, Canton H, Bervoets K, Millan MJ, Laubie M, Lavielle G (1992) S-14506: a novel, potent, high-efficacy 5-HT1A agonist and potential anxiolytic agent. Drug Dev Res 26: 21–48
Cossery JM, Gozlan H, Spampinato U, Perdicakis C, Guillaumet G, Pichat L, Hamon M (1987) The selective labeling of central 5-HT1A receptor binding sites by [3H]5-methoxy-3-(di-n-propylamino)chroman. Eur J Pharmacol 140: 143–155
Dompert W, Glaser T, Traber J (1985)3H-TVX Q 7821: identification of 5-HT1 binding sites as target for a novel putative anxiolytic. Naunyn Schmiedebergs Arch Pharmacol 328: 467–470
Glowinski J, Iversen L (1966) Regional studies of catecholamines in the rat brain. I. Disposition of [3H]norepinephrine, [3H]dopamine and [3H]dopa in various regions of the brain. J Neurochem 13: 655–669
Gozlan H, El Mestikawy S, Pichat L, Glowinski J, Hamon M (1983) Identification of presynaptic serotonin autoreceptors using a new ligand3H-PAT. Nature (Lond) 305: 140–142
Gozlan H, Ponchant M, Daval G, Vergé D, Menard F, Vanhove A, Beaucourt JP, Hamon M (1988)125I-Bolton-Hunter-8-methoxy-2-[N-propyl-N-propylamino] tetralin as a new selective radioligand of 5-HT1A sites in the rat brain.In vitro binding and autoradiographic studies. J Pharmacol Exp Ther 244: 751–759
Gozlan H, Thibault S, Laporte AM, Lima L, Hamon M (1995) The selective 5-HT1A antagonist radioligand [3H]WAY 100,635 labels both G-protein-coupled and free 5-HT1A receptors in rat brain membranes. Eur J Pharmacol Mol Pharmacol 288: 173–186
Hall MD, El Mestikawy S, Emerit MB, Pichat L, Hamon M, Gozlan H (1985) [3H]8-hydroxy-2-(di-n-propylamino)tetralin binding to pre- and postsynaptic 5-hydroxytryptamine sites in various regions of the rat brain. J Neurochem 44: 1685–1696
Hall MD, Gozlan H, Emerit MB, El Mestikawy S, Pichat L, Hamon M (1986) Differentiation of pre- and postsynaptic high affinity serotonin receptor binding sites using physicochemical parameters and modifying agents. Neurochem Res 11: 891–912
Hamon M (1997) The main features of central 5-HT1A receptors. In: Göthert M, Baumgarten HG (eds) Serotoninergic neurons and 5-HT receptors in the CNS. Handbook of experimental pharmacology, vol 29. Springer, Berlin Heidelberg New York Tokyo, pp 239–268
Hoyer D, Clarke D, Fozard JR, Hartig PR, Martin G, Mylecharane E, Saxena P, Humphrey PPA (1994) VII. International Union of Pharmacology classification of receptors for 5-hydroxytryptamine (serotonin). Pharmacol Rev 46: 157–203
Hume SP, Ashworth S, Opacka-Juffry J, Ahier RG, Lammertsma AA, Pike VW, Cliffe IA, Fletcher A, White AC (1994) Evaluation of [O-methyl-3H]WAY-100,635 as an in vivo radioligand for 5-HT1A receptors in rat brain. Eur J Pharmacol 271: 515–523
Khawaja X (1995) Quantitative autoradiographic characterisation of the binding of [3H]WAY-100,635, a selective 5-HT1A receptor antagonist. Brain Res 673: 217–225
Kung MP, Zhuang ZP, Frederick D, Kung HF (1994) In vivo binding of [123I] 4-(2′-methoxy-phenyl)-1-[2′-(N-2″-pyridinyl)-p-iodobenzamido]-ethyl-piperazine, p-MPPI, to 5-HT1A receptors in rat brain. Synapse 18: 359–366
Kung MP, Frederick D, Mu M, Zhuang ZP, Kung HK (1995) 4-(2′-Methoxy-phenyl)-1-[2′-(n-2″-pyridinyl)-p-iodobenzamido]-ethyl-piperazine ([125I]p-MPPI) as a new selective radioligand of serotonin-1A sites in rat brain: in vitro binding and autoradiographic studies. J Pharmacol Exp Ther 272: 429–437
Lanfumey L, Haj-Dahmane S, Hamon M (1993) Further assessment of the antagonist properties of the novel and selective 5-HT1A receptor ligands (+)WAY 100,135 and SDZ 216-525. Eur J Pharmacol 249: 25–35
Laporte AM, Lima L, Gozlan H, Hamon M (1994) Selective in vivo labelling of brain 5-HT1A receptors by [3H]WAY 100,635 in the mouse. Eur J Pharmacol 271: 505–514
Lowry OH, Rosebough NJ, Farr AL, Randall RJ (1951) Protein measurement with the Folin phenol reagent. J Biol Chem 193: 265–275
Middlemiss DN, Fozard JR (1983) 8-Hydroxy-2-(di-n-propylamino)tetralin discriminates between subtypes of the 5-HT1 recognition site. Eur J Pharmacol 30: 151–153
Millan MJ, Rivet JM, Canton H, Le Marouille-Girardon S, Gobert A (1993) Induction of hypothermia as a model of 5-hydroxytryptamine1A receptor-mediated activity in the rat: a pharmacological characterization of the actions of novel agonists and antagonists. J Pharmacol Exp Ther 264: 1364–1376
Mongeau R, Welne SA, Quirion R, Suranyi-Cadotte BE (1992) Further evidence for differential affinity states of the serotonin1A receptor in rat hippocampus. Brain Res 590: 229–238
Nelson DL, Herbet A, Bourgoin S, Glowinski J, Hamon M (1978) Characteristics of central 5-HT receptors and their adaptive changes following intracerebral 5,7-dihydroxytryptamine administration in the rat. Mol Pharmacol 14: 983–995
Newman-Tancredi A, Chaput C, Verrièle L, Millan MJ (1996) S 15535 and WAY 100,635 antagonise 5-HT-stimulated [35S]GTPγS binding at cloned human 5-HT1A receptors. Eur J Pharmacol 307: 107–111
Norman AB, Battaglia G, Creese L (1985) [3H]WB4101 labels the 5-HT1A serotonin receptor subtype in rat brain. Mol Pharmacol 28: 487–494
Pazos A, Palacios JM (1985) Quantitative autoradiographic mapping of serotonin receptors in the rat brain. I. Serotonin-1 receptors. Brain Res 346: 205–230
Pike VW, McCarron JA, Lammerstma AA, Hume SP, Poole K, Grasby PM, Malizia A, Cliffe IA, Fletcher A, Bench CJ (1995) First delineation of 5-HT1A receptors in human brain with PET and [11C]WAY-100,635. Eur J Pharmacol 283: R1-R3
Radja F, Laporte AM, Daval G, Vergé D, Gozlan H, Hamon M (1991) Autoradiography of serotonin receptor subtypes in the central nervous system. Neurochem Int 18: 1–15
Ransom RW, Asarch KB, Shih JC (1986) [3H]1-[2-(4-aminophenyl)ethyl]-4-(3-trifluoromethylphenyl)piperazine: a selective radioligand for 5-HT1A receptors in rat brain. J Neurochem 46: 68–75
Snedecor GW, Cochran WG (1967) Statistical methods. Iowa State College Press, Ames, IA
Stanton JA, Beer MS (1997) Characterisation of a cloned human 5-HT1A receptor cell line using [35S]GTPγS binding. Eur J Pharmacol 320: 267–275
Stratford CA, Tan GL, Hamblin MW, Ciaranello RD (1988) Differential inactivation of G protein reconstitution of subtypes of [3H]5-hydroxytryptamine binding sites in brain. Mol Pharmacol 34: 527–536
Sundaram H, Turner JD, Strange PG (1995) Characterisation of recombinant serotonin 5-HT1A receptors expressed in Chinese hamster ovary cells: the agonist [3H]lisuride labels free receptor and receptor coupled to G protein. J Neurochem 65: 1909–1916
Teicher MH (1983) ALLFIT (Applesoft). Biochemical computing technology information center. Nashville, TN
Vergé D, Daval G, Marcinkiewicz M, Patey A, El Mestikawy S, Gozlan H, Hamon M (1986) Quantitative autoradiography of multiple 5-HT1 receptor subtypes in the brain of control and 5,7-dihydroxytryptamine-treated rats. J Neurosci 6: 3474–3482
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Lima, L., Laporte, A.M., Gaymard, C. et al. Atypical in vitro and in vivo binding of [3H]S-14506 to brain 5-HT1A receptors. J. Neural Transmission 104, 1059–1075 (1997). https://doi.org/10.1007/BF01273319
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DOI: https://doi.org/10.1007/BF01273319