Skip to content
Licensed Unlicensed Requires Authentication Published by De Gruyter February 5, 2014

Molecular imaging of the serotonin 5-HT7 receptors: from autoradiography to positron emission tomography

Luc Zimmer and Thierry Billard


Serotonin and its various receptors are involved in numerous brain functions and neuropsychiatric disorders. Of the 14 known serotoninergic receptors, the 5-HT7 receptor is the most recently identified and characterized. It is closely involved in the pathogenesis of depression, anxiety, epilepsy and pain and is therefore an important target for drug therapy. It is a crucial target in neuroscience, and there is a clear need for radioligands for in vitro and in vivo visualization and quantification, first in animal models and ultimately in humans. This review focuses on the main radioligands suggested for in vitro and in vivo imaging of the 5-HT7 receptor.

Corresponding author: Luc Zimmer, University of Lyon 1, CNRS, INSERM, Lyon Neuroscience Research Center (CRNL), Lyon, France, e-mail: ; and Hospices Civils de Lyon, 59 Boulevard Pinel, 69003 Lyon, France


Andriès, J., Lemoine, L., Mouchel-Blaisot, A., Tang, S., Verdurand, M., Le Bars, D., Zimmer, L., and Billard, T. (2010). Looking for a 5-HT7 radiotracer for positron emission tomography. Bioorg. Med. Chem. Lett. 20, 3730–3733.10.1016/j.bmcl.2010.04.076Search in Google Scholar

Andries, J., Lemoine, L., Le Bars, D., Zimmer, L., and Billard, T. (2011). Synthesis and radiolabelling of potent 5 HT7 receptor PET radiotracers. Eur. J. Med. Chem. 46, 3455–3461.10.1016/j.ejmech.2011.05.010Search in Google Scholar

Bard, J.A., Zgombick, J., Adham, N., Vaysse, P., Branchek, T.A., and Weinshank, R.L. (1993). Cloning of a novel human serotonin receptor (5-HT7) positively linked to adenylate cyclase. J. Biol. Chem. 268, 23422–23426.10.1016/S0021-9258(19)49479-9Search in Google Scholar

Bonaventure, P., Nepomuceno, D., Kwok, A., Chai, W., Langlois, X., Hen, R., Stark, K., Carruthers, N., and Lovenberg, T.W. (2002). Reconsideration of 5-hydroxytryptamine (5-HT)7 receptor distribution using [3H]5-CT and [3H]8-hydroxy-2-(di-n-propylamino)tetraline: analysis in brain of 5-HT1A knockout and 5-HT1A/1B double-knockout mice. J. Pharmacol. Exp. Ther. 302, 240–248.10.1124/jpet.302.1.240Search in Google Scholar

Bonaventure, P., Kelly, L., Aluisio, L., Shelton, J., Lord, B., Galici, R., Miller, K., Atack, J., Lovenberg, T.W., and Dugovic, C. (2007). Selective blockade of 5-hydroxytryptamine (5-HT)7 receptors enhances 5-HT transmission, antidepressant-like behavior, and rapid eye movement sleep suppression induced by citalopram in rodents. J. Pharmacol. Exp. Ther. 321, 690–698.10.1124/jpet.107.119404Search in Google Scholar

Bourson, A., Kapps, V., Zwingelstein, C., Rudler, A., Boess, F.G., and Sleight, A.J. (1997). Correlation between 5-HT7 receptor affinity and protection against sound-induced seizures in DBA/2J mice. Naunyn Schmiedebergs Arch. Pharmacol. 356, 820–826.Search in Google Scholar

Brenchat, A., Romero, L., García, M., Pujol, M., Burgueño, J., Torrens, A., Hamon, M., Baeyens, J.M., Buschmann, H., Zamanillo, D., et al. (2009). 5-HT7 receptor activation inhibits mechanical hypersensitivity secondary to capsaicin sensitization in mice. Pain 141, 239–247.10.1016/j.pain.2008.11.009Search in Google Scholar

Colomb, J., Becker, G., Forcellini, E., Meyer, S., Buisson, L., Zimmer, L., and Billard, T. (2014). Synthesis and pharmacological evaluation of a new series of radiolabeled ligands for 5-HT7 receptor PET neuroimaging. Nucl. Med. Biol. In press.10.1016/j.nucmedbio.2014.01.008Search in Google Scholar

Dean, B., Pavey, G., Thomas, D., and Scarr, E. (2006). Cortical serotonin7, 1D and 1F receptors: effects of schizophrenia, suicide and antipsychotic drug treatment. Schizophr. Res. 88, 265–274.10.1016/j.schres.2006.07.003Search in Google Scholar

Drew, M.R. and Hen, R. (2007). Adult hippocampal neurogenesis as target for the treatment of depression. CNS Neurol. Disord. Drug Targets 6, 205–218.10.2174/187152707780619353Search in Google Scholar

Duncan, M.J. and Franklin, K.M. (2007). Expression of 5-HT7 receptor mRNA in the hamster brain: effect of aging and association with calbindin-D28K expression. Brain Res. 1143, 70–77.10.1016/j.brainres.2007.01.044Search in Google Scholar

Duncan, M.J., Short, J., and Wheeler D.L. (1999). Comparison of the effects of aging on 5-HT7 and 5-HT1A receptors in discrete regions of the circadian timing system in hamsters. Brain Res. 829, 39–45.10.1016/S0006-8993(99)01311-6Search in Google Scholar

Faure, C., Mnie-Filali, O., Scarna, H., Debonnel, G., and Haddjeri, N. (2006). Effects of the 5-HT7 receptor antagonist SB-269970 on rat hormonal and temperature responses to the 5-HT1A/7 receptor agonist 8-OH-DPAT. Neurosci Lett. 404, 122–126.10.1016/j.neulet.2006.05.023Search in Google Scholar

Forbes, I.T., Dabbs, S., Duckworth, D.M., Jennings, A.J., King, F.D., Lovell, P.J., Collin, L., Brown, A.M., Hagan, J.J., Middlemiss, D.N., et al. (1998). (R)-3,N-Dimethyl-N-[1-methyl-3-(4-methylpiperidin-1-yl)propyl]benzene sulfonamide: the first selective 5-HT7 receptor antagonist. J. Med. Chem. 41, 655–657.10.1021/jm970519eSearch in Google Scholar

Freret, T., Paizanis, E., Beaudet, G., Gusmao-Montaigne, A., Nee, G., Dauphin, F., Bouet, V., and Boulouard, M. (2014). Modulation of 5-HT7 receptor: effect on object recognition performances in mice. Psychopharmacology 231, 393–400.10.1007/s00213-013-3247-xSearch in Google Scholar

Graf, M., Jakus, R., Kantor, S., Levay, G., and Bagdy, G. (2004). Selective 5-HT1A and 5-HT7 antagonists decrease epileptic activity in the WAG/Rij rat model of absence epilepsy. Neurosci. Lett. 359, 45–48.10.1016/j.neulet.2004.01.072Search in Google Scholar

Guscott, M., Bristow, L.J., Hadingham, K., Rosahl, T.W., Beer, M.S., Stanton, J.A., Bromidge, F., Owens, A.P., Huscroft, I., Myers, J., et al. (2005). Genetic knockout and pharmacological blockade studies of the 5-HT7 receptor suggest therapeutic potential in depression. Neuropharmacology 48, 492–502.10.1016/j.neuropharm.2004.11.015Search in Google Scholar

Gustafson, E.L., Durkin, M.M., Bard, J.A., Zgombick, J., and Branchek, T.A. (1996). A receptor autoradiographic and in situ hybridization analysis of the distribution of the 5-HT7 receptor in rat brain. Br. J. Pharmacol. 117, 657–666.10.1111/j.1476-5381.1996.tb15241.xSearch in Google Scholar

Halldin, C., Gulyás, B., Langer, O., and Farde, L. (2001). Brain radioligands – state of the art and new trends. Q. J. Nucl. Med. 45, 139–152.Search in Google Scholar

Hagan, J.J., Price, G.W., Jeffrey, P., Deeks, N.J., Stean, T., Piper, D., Smith, M.I., Upton, N., Medhurst, A.D., Middlemiss, D.N., et al. (2000). Characterization of SB-269970-A, a selective 5-HT7 receptor antagonist. Br. J. Pharmacol. 130, 539–548.10.1038/sj.bjp.0703357Search in Google Scholar

Heckl, S., Pipkorn, R., Nägele, T., Vogel, U., Küker, W., and Voight, K. (2004). Molecular imaging: Bridging the gap between neuroradiology and neurohistology. Histol. Histopathol. 19, 651–668.Search in Google Scholar

Hedlund, P.B. (2009). The 5-HT7 receptor and disorders of the nervous system: an overview. Psychopharmacology 206, 345–354.10.1007/s00213-009-1626-0Search in Google Scholar

Hedlund, P.B. and Sutcliffe, J.G. (2004). Functional, molecular and pharmacological advances in 5-HT7 receptor research. Trends Pharmacol. Sci. 25, 481–486.10.1016/ in Google Scholar

Hedlund, P.B., Huitron-Resendiz, S., Henriksen, S.J., and Sutcliffe, J.G. (2005). 5-HT7 receptor inhibition and inactivation induce antidepressantlike behavior and sleep pattern. Biol. Psychiatry 58, 831–837.10.1016/j.biopsych.2005.05.012Search in Google Scholar

Hemedah, M., Coupar, I.M., and Mitchelson, F.J. (1999). [3H]Mesulergine labels 5-HT7 sites in rat brain and guinea-pig ileum but not rat jejunum. Br. J. Pharmacol. 126, 179–188.10.1038/sj.bjp.0702293Search in Google Scholar

Herth, M.M., Volk, B., Pallagi, K., Kofoed Bech, L., Antoni, F.A., Knudsen, G.M., and Kristensen, J.L. (2012a). Synthesis and in vitro evaluation of oxindole derivatives as potential radioligands for 5-HT7 receptor imaging with PET. ACS Chem. Neuroscience 3, 1002–1007.10.1021/cn3001137Search in Google Scholar

Herth, M.M., Hansen, H.D., Ettrup, A., Dyssegaard, A., Lehel, S., Kristensen, J., and Knudsen, G.M. (2012b). Synthesis and evaluation of [¹¹C]Cimbi-806 as a potential PET ligand for 5-HT7 receptor imaging. Bioorg. Med. Chem. 20, 4574–4581.10.1016/j.bmc.2012.05.005Search in Google Scholar

Horisawa, T., Ishiyama, T., Ono, M., Ishibashi, T., and Taiji, M. (2013). Binding of lurasidone, a novel antipsychotic, to rat 5-HT7 receptor: analysis by [3H]SB-269970 autoradiography. Prog. Neuropsychopharmacol. Biol. Psychiatry 40, 132–137.10.1016/j.pnpbp.2012.08.005Search in Google Scholar

Irving, H.R., Tan, Y.Y., Tochon-Danguy, N., Liu, H., Chetty, N., Desmond, P.V., Pouton, C.W., and Coupar, I.M. (2007). Comparison of 5-HT4 and 5-HT7 receptor expression and function in the circular muscle of the human colon. Life Sci. 80, 1198–1205.10.1016/j.lfs.2006.12.025Search in Google Scholar

IUPAHR Database. (2013). Available at Accessed November 2013.Search in Google Scholar

Jones, B.J. and Blackburn, T.P. (2002). The medical benefit of 5-HT research. Pharmacol. Biochem. Behav. 71, 555–568.10.1016/S0091-3057(01)00745-6Search in Google Scholar

Kikuchi, C., Ando, T., Watanabe, T., Nagaso, H., Okuno, M., Hiranuma, T., and Koyama, M. (2002). 2a-[4-(Tetrahydropyridoindol-2-yl)butyl]tetrahydrobenzindole derivatives: new selective antagonists of the 5-hydroxytryptamine7 receptor. J. Med. Chem. 45, 2197–2206.10.1021/jm0104264Search in Google Scholar

Kinsey, A.M., Wainwright, A., Heavens, R., Sirinathsinghji, D.J., and Oliver, K.R. (2001). Distribution of 5-HT5A, 5-HT5B, 5-HT6 and 5-HT7 receptor mRNAs in the rat brain. Brain Res. Mol. Brain Res. 88, 194–198.10.1016/S0169-328X(01)00034-1Search in Google Scholar

Krobert, K.A., Bach, T., Syversveen, T., Kvingedal, A.M., and Levy, F.O. (2001). The cloned human 5-HT7 receptor splice variants: a comparative characterization of their pharmacology, function and distribution. Naunyn Schmiedebergs Arch. Pharmacol. 363, 620–632.Search in Google Scholar

Lancelot, S. and Zimmer, L. (2010). Small animal positron emission tomography as a tool for neuropharmacology. Trends Pharmacol. Sci. 31, 411–417.10.1016/ in Google Scholar

Leopoldo, M., Lacivita, E., De Giorgio, P., Fracasso, C., Guzzetti, S., Caccia, S., Contino, M., Colabufo, N.A., Berardi, F., and Perrone, R. (2008). Structural modifications of N-(1,2,3,4-tetrahydronaphthalen-1-yl)-4-aryl-1-piperazinehexanamides: influence on lipophilicity and 5-HT7 receptor activity. J. Med. Chem. 51, 5813–5822.10.1021/jm800615eSearch in Google Scholar

Leopoldo, M., Lacivita, E., Colabufo, N., De Giorgio, P., Berardi, F., and Perrone, R. (2012). New 1-arylpiperazinic ligands of 5-HT7 receptors and use thereof. World Intellectual Property Organization. WO 2012/159662 A1.Search in Google Scholar

Lemoine, L., Andries, J., Le Bars, D., Billard, T., and Zimmer, L. (2011). Comparison of 4 radiolabeled antagonists for serotonin 5-HT7 receptor neuroimaging: toward the first PET radiotracer. J. Nucl. Med. 52, 1811–1818.10.2967/jnumed.111.089185Search in Google Scholar

Lovell, P.J., Bromidge, S., Dabbs, D.M., Duckworth, I.T., Forbes, A.J., Jennings, F.D., King, D.N., Middlemiss, S.K., Rahman, D.V., Saunders, L.L., et al. (2000). A novel, potent, and selective 5-HT7 antagonist: (R)-3-(2-(2-(4-methylpiperidin-yl)ethyl)pyrrolidine-1-sulfonyl)phenol (SB-269970). J. Med. Chem. 43, 342–345.10.1021/jm991151jSearch in Google Scholar

Lovenberg, T.W., Erlander, M.G., Baron, B.M., and Sutcliffe, J.G. (1993). Cloning of new 5-HT receptors. Int. Clin. Psychopharmacol. 8, 19–23.10.1097/00004850-199311002-00003Search in Google Scholar

Malberg, J.E., Eisch, A.J., Nestler, E.J., and Duman, R.S. (2000). Chronic antidepressant treatment increases neurogenesis in adult rat hippocampus. J. Neurosci. 20, 9104–9110.10.1523/JNEUROSCI.20-24-09104.2000Search in Google Scholar

Martín-Cora, F.J. and Pazos, A. (2004). Autoradiographic distribution of 5-HT7 receptors in the human brain using [3H]mesulergine: comparison to other mammalian species. Br. J. Pharmacol. 141, 92–104.10.1038/sj.bjp.0705576Search in Google Scholar

Matthys, A., Haegeman, G., Van Craenenbroeck, K., and Vanhoenacker, P. (2011). Role of the 5-HT7 receptor in the central nervous system: from current status to future perspectives. Mol. Neurobiol. 43, 228–253.10.1007/s12035-011-8175-3Search in Google Scholar

Meneses, A. (1999). 5-HT system and cognition. Neurosci. Biobehav. Rev. 23, 1111–1125.10.1016/S0149-7634(99)00067-6Search in Google Scholar

Meneses, A. (2004). Effects of the 5-HT7 receptor antagonists SB-269970 and DR 4004 in autoshaping Pavlovian/instrumental learning task. Behav. Brain Res. 155, 275–282.10.1016/j.bbr.2004.04.026Search in Google Scholar

Mengod, G., Vilaro, M.T., Raurich, A., Lopez-Gimenez, J.F., Cortes, R., and Palacios, J.M. (1996). 5-HT receptors in mammalian brain: receptor autoradiography and in situ hybridization studies of new ligands and newly identified receptors. Histochem. J. 28, 747–758.10.1007/BF02272148Search in Google Scholar

Mnie-Filali, O., Lambás-Señas, L., Zimmer, L., and Haddjeri, N. (2007). 5-HT7 receptor antagonists as a new class of antidepressants. Drug News Perspect. 20, 613–618.10.1358/dnp.2007.20.10.1181354Search in Google Scholar

Mnie-Filali, O., Faure, C., Lambás-Señas, L., El Mansari, M., Belblidia, H., Gondard, E., Etiévant, A., Scarna, H., Didier, A., Berod, A., et al. (2011). Pharmacological blockade of 5-HT7 receptors as a putative fast acting antidepressant strategy. Neuropsychopharmacology 36, 1275–1288.10.1038/npp.2011.13Search in Google Scholar

Neumaier, J.F., Sexton, T.J., Yracheta, J., Diaz, A.M., and Brownfield, M. (2001). Localization of 5-HT7 receptors in rat brain by immunocytochemistry, in situ hybridization and agonist stimulated cFos expression. J. Chem. Neuroanat. 21, 63–73.10.1016/S0891-0618(00)00092-2Search in Google Scholar

Paillet-Loilier, M., Fabis, F., Lepailleur, A., Bureau, R., Butt-Gueulle, S., Dauphin, F., Lesnard, A., Delarue, C., Vaudry, H., and Rault, S. (2007). Novel aminoethylbiphenyls as 5-HT7 receptor ligands. Bioorg. Med. Chem. Lett. 17, 3018–3022.10.1016/j.bmcl.2007.03.054Search in Google Scholar

Pien, H.H., Fischman, A.J., Thrall, J.H., and Sorensen, A.G. (2005). Using imaging biomarkers to accelerate drug development and clinical trials. Drug Discov. Today 10, 259–266.10.1016/S1359-6446(04)03334-3Search in Google Scholar

Plassat, J.L., Amlaiky, N., and Hen, R. (1993). Molecular cloning of a mammalian serotonin receptor that activates adenylate cyclase. Mol. Pharmacol. 44, 229–236.Search in Google Scholar

Pérez-García, G., Gonzalez-Espinosa, C., and Meneses, A. (2006). An mRNA expression analysis of stimulation and blockade of 5-HT7 receptors during memory consolidation. Behav. Brain Res. 169, 83–92.10.1016/j.bbr.2005.12.013Search in Google Scholar

Pittalà, V., Salerno, L., Modica, M., Siracusa, M.A., and Romeo, G. (2007). 5-HT7 Receptor ligands: recent developments and potential therapeutic applications. Mini-Rev. Med. Chem. 7, 945–960.10.2174/138955707781662663Search in Google Scholar

Rocha-González, H.I., Meneses, A., Carlton, S.M., and Granados-Soto, V. (2005). Pronociceptive role of peripheral and spinal 5-HT7 receptors in the formalin test. Pain 117, 182–192.10.1016/j.pain.2005.06.011Search in Google Scholar

Roberts, A.J., Krucker, T., Levy, C.L., Salina, K.A., Sutcliffe, J.G., and Hedlund, P.B. (2004). Mice lacking 5-HT receptors show specific impairments in contextual learning. Eur. J. Neurosci. 19, 1913–1922.10.1111/j.1460-9568.2004.03288.xSearch in Google Scholar

Roth, B.L., Craig, S.C., Choudhary, M.S., Uluer, A., Monsma, F.J. Jr., Shen, Y., Meltzer, H.Y., and Sibley, D.R. (1994). Binding of typical and atypical antipsychotic agents to 5-hydroxytryptamine-6 and 5 hydroxytryptamine-7 receptors. J. Pharmacol. Exp. Ther. 268, 1403–1410.Search in Google Scholar

Ruocco, L.A., Romano, E., Treno, C., Lacivita, E., Claudio, A., Gironi-Carnevale, U.A., Travaglini, D., Leopoldo, M., Laviola, G., Sadile, A.G., et al. (2014). Emotional and risk seeking behavior after prepuberal subchronic or adult acute stimulation of 5-HT7-Rs in naples high excitability rats. Synapse. In press.10.1002/syn.21724Search in Google Scholar

Schoeffter, P., Ullmer, C., Bobirnac, I., Gabbiani, G., and Lübbert, H. (1996). Functional, endogenously expressed 5-hydroxytryptamine 5-ht7 receptors in human vascular smooth muscle cells. Br. J. Pharmacol. 117, 993–994.10.1111/j.1476-5381.1996.tb16687.xSearch in Google Scholar

Shimoda, Y., Yui, J., Xie, L., Fujinaga, M., Yamasaki, T., Ogawa, M., Nengaki, N., Kumata, K., Hatori, A., Kawamura, K., et al. (2013). Synthesis and evaluation of 1-[2-(4-[11C]methoxyphenyl)phenyl]piperazine for imaging of the serotonin 5-HT7 receptor in the rat brain. Bioorg. Med. Chem. 21, 5316–5322.10.1016/j.bmc.2013.06.020Search in Google Scholar

Stowe, R.L. and Barnes, N.M. (1998). Selective labeling of 5-HT7 receptor recognition sites in rat brain using [3H]5-carboxamidotryptamine. Neuropharmacology 37, 1611–1619.10.1016/S0028-3908(98)00117-8Search in Google Scholar

Thomas, D.R., Atkinson, P.A., Ho, M., Bromidge, S.M., Lovell, P.J., Hagan, J.J., Middlemiss, D.N., and Price, G.W. (2000). [3H]-SB-269970 – a selective antagonist radioligand for 5-HT7 receptors. Br. J. Pharmacol. 130, 409–417.10.1038/sj.bjp.0703318Search in Google Scholar

Thomas, D.R., Atkinson, P.J., Hastie, P.G., Roberts, J.C., Middlemiss, D.N., and Price, G.W. (2002). [3H]-SB-269970 radiolabels 5-HT7 receptors in rodent, pig and primate brain tissues. Neuropharmacology 42, 74–81.10.1016/S0028-3908(01)00151-4Search in Google Scholar

To, Z.P., Bonhaus, D.W., Eglen, R.M., and Jakeman, L.B. (1995).Characterization and distribution of putative 5-HT7 receptors in guinea-pig brain. Br. J. Pharmacol. 115, 107–116.10.1111/j.1476-5381.1995.tb16327.xSearch in Google Scholar

Varnäs, K., Thomas, D.R., Tupala, E., Tiihonen, J., and Hall, H. (2004). Distribution of 5-HT7 receptors in the human brain: a preliminary autoradiographic study using [3H]SB-269970. Neurosci. Lett. 367, 313–316.10.1016/j.neulet.2004.06.025Search in Google Scholar

Volk, B., Barkoczy, J., Hegedus, E., Udvari, S., Gacsalyi, I., Mezei, T., Pallagi, K., Kompagne, H., Levay, G., Egyed, A., et al. (2008). Phenylpiperazinyl-butyl)oxindoles as selective 5-HT7 receptor antagonists. J. Med. Chem. 51, 2522−2532.10.1021/jm070279vSearch in Google Scholar

Volk, B., Gacsalyi, I., Pallagi, K., Poszavacz, L., Gyonos, I., Szabo, E., Bako, T., Spedding, M., Simig, G., and Szenasi, G. (2011). Optimization of (arylpiperazinylbutyl)oxindoles exhibiting selective 5-HT7 receptor antagonist activity. J. Med. Chem. 54, 6657−6669.10.1021/jm200547zSearch in Google Scholar

Waeber, C. and Moskowitz, M.A. (1995). Autoradiographic visualisation of [3H]5-carboxamidotryptamine binding sites in the guinea pig and rat brain. Eur. J. Pharmacol. 283, 31–46.10.1016/0014-2999(95)00275-PSearch in Google Scholar

Wesołowska, A., Nikiforuk, A., Stachowicz, K., and Tatarczyńska, E. (2006). Effect of the selective 5-HT7 receptor antagonist SB 269970 in animal models of anxiety and depression. Neuropharmacology 51, 578–586.10.1016/j.neuropharm.2006.04.017Search in Google Scholar

Yoon, J., Yoo, E.A., Kim, J.Y., Pae, A.N., Rhim, H., Park, W.K., Kong, J.Y., and Park Choo, H.Y. (2008). Preparation of piperazine derivatives as 5-HT7 receptor antagonists. Bioorg. Med. Chem. 16, 5405–5412.10.1016/j.bmc.2008.04.023Search in Google Scholar

Zhang, M.R., Haradahira, T., Maeda, J., Okauchi, T., Kida, T., Obayashi, S., Suzuki, K., and Suhara, T. (2002). Synthesis and preliminary PET study of the 5-HT7 receptor antagonist [11C]DR4446. J. Labelled Comp. Radiopharm. 45, 857–866.10.1002/jlcr.606Search in Google Scholar

Zimmer, L. and Le Bars, D. (2013). Current status of positron emission tomography radiotracers for serotonin receptors in humans. J. Labelled Comp. Radiopharm. 56, 105–113.10.1002/jlcr.3001Search in Google Scholar

Zimmer, L. and Luxen, A. (2012). PET radiotracers for molecular imaging in the brain: past, present and future. Neuroimage 61, 363–670.10.1016/j.neuroimage.2011.12.037Search in Google Scholar

Received: 2013-11-25
Accepted: 2014-1-9
Published Online: 2014-2-5
Published in Print: 2014-6-1

©2014 by Walter de Gruyter Berlin/Boston