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Alluri SR, Kim SW, Volkow ND, Kil KE. PET Radiotracers for CNS-Adrenergic Receptors: Developments and Perspectives. Molecules 2020; 25:molecules25174017. [PMID: 32899124 PMCID: PMC7504810 DOI: 10.3390/molecules25174017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/29/2020] [Accepted: 09/01/2020] [Indexed: 12/30/2022] Open
Abstract
Epinephrine (E) and norepinephrine (NE) play diverse roles in our body’s physiology. In addition to their role in the peripheral nervous system (PNS), E/NE systems including their receptors are critical to the central nervous system (CNS) and to mental health. Various antipsychotics, antidepressants, and psychostimulants exert their influence partially through different subtypes of adrenergic receptors (ARs). Despite the potential of pharmacological applications and long history of research related to E/NE systems, research efforts to identify the roles of ARs in the human brain taking advantage of imaging have been limited by the lack of subtype specific ligands for ARs and brain penetrability issues. This review provides an overview of the development of positron emission tomography (PET) radiotracers for in vivo imaging of AR system in the brain.
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Affiliation(s)
- Santosh Reddy Alluri
- University of Missouri Research Reactor, University of Missouri, Columbia, MO 65211-5110, USA;
| | - Sung Won Kim
- Laboratory of Neuroimaging, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892-1013, USA;
| | - Nora D. Volkow
- Laboratory of Neuroimaging, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892-1013, USA;
- National Institute on Drug Abuse, National Institutes of Health, Bethesda, MD 20892-1013, USA
- Correspondence: (N.D.V.); (K.-E.K.); Tel.: +1-(301)-443-6480 (N.D.V.); +1-(573)-884-7885 (K.-E.K.)
| | - Kun-Eek Kil
- University of Missouri Research Reactor, University of Missouri, Columbia, MO 65211-5110, USA;
- Department of Veterinary Medicine and Surgery, University of Missouri, Columbia, MO 65211, USA
- Correspondence: (N.D.V.); (K.-E.K.); Tel.: +1-(301)-443-6480 (N.D.V.); +1-(573)-884-7885 (K.-E.K.)
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Molecular Imaging of the Noradrenergic System in Idiopathic Parkinson's Disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2018; 141:251-274. [DOI: 10.1016/bs.irn.2018.07.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Finnema SJ, Hughes ZA, Haaparanta-Solin M, Stepanov V, Nakao R, Varnäs K, Varrone A, Arponen E, Marjamäki P, Pohjanoksa K, Vuorilehto L, Babalola PA, Solin O, Grimwood S, Sallinen J, Farde L, Scheinin M, Halldin C. Amphetamine decreases α2C-adrenoceptor binding of [11C]ORM-13070: a PET study in the primate brain. Int J Neuropsychopharmacol 2015; 18:pyu081. [PMID: 25522417 PMCID: PMC4360244 DOI: 10.1093/ijnp/pyu081] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The neurotransmitter norepinephrine has been implicated in psychiatric and neurodegenerative disorders. Examination of synaptic norepinephrine concentrations in the living brain may be possible with positron emission tomography (PET), but has been hampered by the lack of suitable radioligands. METHODS We explored the use of the novel α2C-adrenoceptor antagonist PET tracer [(11)C]ORM-13070 for measurement of amphetamine-induced changes in synaptic norepinephrine. The effect of amphetamine on [(11)C]ORM-13070 binding was evaluated ex vivo in rat brain sections and in vivo with PET imaging in monkeys. RESULTS Microdialysis experiments confirmed amphetamine-induced elevations in rat striatal norepinephrine and dopamine concentrations. Regional [(11)C]ORM-13070 receptor binding was high in the striatum and low in the cerebellum. After injection of [(11)C]ORM-13070 in rats, mean striatal specific binding ratios, determined using cerebellum as a reference region, were 1.4±0.3 after vehicle pretreatment and 1.2±0.2 after amphetamine administration (0.3mg/kg, subcutaneous). Injection of [(11)C]ORM-13070 in non-human primates resulted in mean striatal binding potential (BP ND) estimates of 0.65±0.12 at baseline. Intravenous administration of amphetamine (0.5 and 1.0mg/kg, i.v.) reduced BP ND values by 31-50%. Amphetamine (0.3mg/kg, subcutaneous) increased extracellular norepinephrine (by 400%) and dopamine (by 270%) in rat striata. CONCLUSIONS Together, these results indicate that [(11)C]ORM-13070 may be a useful tool for evaluation of synaptic norepinephrine concentrations in vivo. Future studies are required to further understand a potential contribution of dopamine to the amphetamine-induced effect.
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Affiliation(s)
- Sjoerd J Finnema
- Karolinska Institutet, Department of Clinical Neuroscience, Center for Psychiatric Research, Stockholm, Sweden (Drs Finnema, Stepanov, Nakao, Varnäs, Varrone, Farde, and Halldin); Pfizer, Neuroscience Research Unit, Cambridge, MA (Drs Hughes, Babalola, and Grimwood); University of Turku, Turku PET Centre, Turku, Finland (Drs Haaparanta-Solin, Arponen, Marjamäki, and Solin); University of Turku, Department of Pharmacology, Drug Development and Therapeutics, and Turku University Hospital, Unit of Clinical Pharmacology, Turku, Finland (Drs Pohjanoksa, Vuorilehto, and Scheinin); Orion Corporation, Orion Pharma, Research and Development, Turku, Finland (Dr Sallinen); AstraZeneca, Translational Science Center at Karolinska Institutet, Stockholm, Sweden (Dr Farde)
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Airaksinen AJ, Finnema SJ, Balle T, Varnäs K, Bang-Andersen B, Gulyás B, Farde L, Halldin C. Radiosynthesis and evaluation of new α1-adrenoceptor antagonists as PET radioligands for brain imaging. Nucl Med Biol 2013; 40:747-54. [PMID: 23810488 DOI: 10.1016/j.nucmedbio.2013.05.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 05/06/2013] [Accepted: 05/18/2013] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Evaluation of the α1-adrenoceptors in relation to brain pathophysiology and drug treatment has been hindered by lack of α1-adrenoceptor specific radioligands with sufficient brain exposure. Our aim was to develop an α1-adrenoceptor specific PET radioligand for brain imaging. METHODS Two sertindole analogues 1-(4-fluorophenyl)-5-(1-methyl-1H-1,2,4-triazol-3-yl)-3-(1-[(11)C]methylpiperidin-4-yl)-1H-indole [(11)C]3 and 1-(4-fluorophenyl)-3-(1-[(11)C]methylpiperidin-4-yl)-5-(pyrimidin-5-yl)-1H-indole ([(11)C]Lu AA27122) [(11)C]4 were synthesized and evaluated as α1-adrenoceptor PET radioligands in cynomolgus monkey. Compounds 3 and 4 were selected due to their promising in vitro preclinical profile; high affinity and selectivity for the α1-adrenoceptor, favourable blood brain barrier permeability rates in Caco-2 monolayers and promising brain tissue/plasma ratio, assessed by equilibrium dialysis of free fraction in plasma and brain homogenate. RESULTS Compounds [(11)C]3 and [(11)C]4 were synthesized from their desmethyl piperidine precursors with high specific radioactivity (>370 GBq/μmol) using [(11)C]methyl iodide. The 1,2,4-triazole analogue [(11)C]3 exhibited poor brain uptake, but the corresponding pyrimidyl analogue [(11)C]4 exhibited high brain exposure and binding in α1-adrenoceptor rich brain regions. However, the binding could not be inhibited by pretreatment with prazosin (0.1 mg/kg and 0.3 mg/kg). The results were extended by autoradiography of [(11)C]4 binding in human brain sections and competition with antagonists from different structural families, revealing that only a minor portion of the observed binding of [(11)C]4 in brain was α1-adrenoceptor specific. CONCLUSION Though [(11)C]3 and [(11)C]4 proved not suitable as PET radioligands, the study provided further understanding of structural features influencing brain exposure of the chemical class of compounds related to the antipsychotic drug sertindole. It provided valuable insight in the delicacy of blood brain barrier penetration for structurally related compounds and underlines the importance for improved protocols for evaluation of brain penetration of future PET ligands.
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Affiliation(s)
- Anu J Airaksinen
- Department of Clinical Neuroscience, Psychiatry Section, Karolinska Institutet, Karolinska Hospital, S-17176 Stockholm, Sweden.
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Risgaard R, Ettrup A, Balle T, Dyssegaard A, Hansen HD, Lehel S, Madsen J, Pedersen H, Püschl A, Badolo L, Bang-Andersen B, Knudsen GM, Kristensen JL. Radiolabelling and PET brain imaging of the α1-adrenoceptor antagonist Lu AE43936. Nucl Med Biol 2013; 40:135-40. [DOI: 10.1016/j.nucmedbio.2012.09.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 09/10/2012] [Accepted: 09/27/2012] [Indexed: 10/27/2022]
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Jørgensen M, Jørgensen PN, Christoffersen CT, Jensen KG, Balle T, Bang-Andersen B. Discovery of novel α₁-adrenoceptor ligands based on the antipsychotic sertindole suitable for labeling as PET ligands. Bioorg Med Chem 2012; 21:196-204. [PMID: 23218776 DOI: 10.1016/j.bmc.2012.10.049] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Revised: 09/20/2012] [Accepted: 10/25/2012] [Indexed: 11/26/2022]
Abstract
The synthesis and in vitro preclinical profile of a series of 5-heteroaryl substituted analogs of the antipsychotic drug sertindole are presented. Compounds 1-(4-fluorophenyl)-3-(1-methylpiperidin-4-yl)-5-(pyrimidin-5-yl)-1H-indole (Lu AA27122, 3i) and 1-(4-fluorophenyl)-5-(1-methyl-1H-1,2,4-triazol-3-yl)-3-(1-methylpiperidin-4-yl)-1H-indole (3l) were identified as high affinity α(1A)-adrenoceptor ligands with K(i) values of 0.52 and 0.16 nM, respectively, and with a >100-fold selectivity versus dopamine D(2) receptors. Compound 3i showed almost equal affinity for α(1B)- (K(i)=1.9 nM) and α(1D)-adrenoceptors (K(i)=2.5 nM) as for α(1A), as well as moderate affinity for 5-HT(1B) (K(i)=13 nM) and 5-HT(6) (K(i)=16 nM) receptors, whereas 3l showed >40-fold selectivity toward all other targets tested. Based on in vitro assays for assessment of permeability rates and extent, it is predicted that both compounds enter the brain of rats, non-human primates, as well as humans, and as such are good candidates to be carried forward for further evaluation as positron emission tomography (PET) ligands.
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Affiliation(s)
- Morten Jørgensen
- Neuroscience Drug Discovery Denmark, H. Lundbeck A/S, 9 Ottiliavej, DK-2500 Copenhagen-Valby, Denmark
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Moons T, de Roo M, Claes S, Dom G. Relationship between P-glycoprotein and second-generation antipsychotics. Pharmacogenomics 2011; 12:1193-211. [PMID: 21843066 DOI: 10.2217/pgs.11.55] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The membrane transport protein P-glycoprotein (P-gp) is an interesting candidate for individual differences in response to antipsychotics. To present an overview of the current knowledge of P-gp and its interaction with second-generation antipsychotics (SGAs), an internet search for all relevant English original research articles concerning P-gp and SGAs was conducted. Several SGAs are substrates for P-gp in therapeutic concentrations. These include amisulpride, aripiprazole, olanzapine, perospirone, risperidone and paliperidone. Clozapine and quetiapine are not likely to be substrates of P-gp. However, most antipsychotics act as inhibitors of P-gp, and can therefore influence plasma and brain concentrations of other substrates. No information was available for sertindole, ziprasidone or zotepine. Research in animal models demonstrated significant differences in antipsychotic brain concentration and behavior owing to both P-gp knockout and inhibition. Results in patients are less clear, as several external factors have to be accounted for. Patients with polymorphisms which decrease P-gp functionality tend to perform better in clinical settings. There is some variability in the findings concerning adverse effects, and no definitive conclusions can be drawn at this point.
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Affiliation(s)
- Tim Moons
- University Psychiatric Centre, Catholic University Leuven, Herestraat 49, 3000 Leuven, Belgium.
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Kristensen JL, Püschl A, Jensen M, Risgaard R, Christoffersen CT, Bang-Andersen B, Balle T. Exploring the Neuroleptic Substituent in Octoclothepin: Potential Ligands for Positron Emission Tomography with Subnanomolar Affinity for α1-Adrenoceptors. J Med Chem 2010; 53:7021-34. [DOI: 10.1021/jm100652h] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jesper L. Kristensen
- Department of Medicinal Chemistry, The Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | | | - Martin Jensen
- Department of Medicinal Chemistry, The Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
- Medicinal Chemistry Research
| | - Rune Risgaard
- Department of Medicinal Chemistry, The Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
- Medicinal Chemistry Research
| | | | | | - Thomas Balle
- Department of Medicinal Chemistry, The Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
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Laćan G, Plenevaux A, Rubins DJ, Way BM, Defraiteur C, Lemaire C, Aerts J, Luxen A, Cherry SR, Melega WP. Cyclosporine, a P-glycoprotein modulator, increases [18F]MPPF uptake in rat brain and peripheral tissues: microPET and ex vivo studies. Eur J Nucl Med Mol Imaging 2008; 35:2256-66. [PMID: 18604533 DOI: 10.1007/s00259-008-0832-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2007] [Accepted: 05/02/2008] [Indexed: 12/20/2022]
Abstract
PURPOSE Pretreatment with cyclosporine, a P-glycoprotein (P-gp) modulator increases brain uptake of 4-(2'-methoxyphenyl)-1-[2'-(N-2"-pyridinyl)-p-[(18)F]fluorobenzamido]ethylpiperazine ([(18)F]MPPF) for binding to hydroxytryptamine(1A) (5-HT(1A)) receptors. Those increases were quantified in rat brain with in vivo microPET and ex vivo tissue studies. MATERIALS AND METHODS Each Sprague-Dawley rat (n = 4) received a baseline [(18)F]MPPF microPET scan followed by second scan 2-3 weeks later that included cyclosporine pretreatment (50 mg/kg, i.p.). Maximum a posteriori reconstructed images and volumetric ROIs were used to generate dynamic radioactivity concentration measurements for hippocampus, striatum, and cerebellum, with simplified reference tissue method (SRTM) analysis. Western blots were used to semiquantify P-gp regional distribution in brain. RESULTS MicroPET studies showed that hippocampus uptake of [(18)F]MPPF was increased after cyclosporine; ex vivo studies showed similar increases in hippocampus and frontal cortex at 30 min, and for heart and kidney at 2.5 and 5 min, without concomitant increases in [(18)F]MPPF plasma concentration. P-gp content in cerebellum was twofold higher than in hippocampus or frontal cortex. CONCLUSIONS These studies confirm and extend prior ex vivo results (J. Passchier, et al., Eur J Pharmacol, 2000) that showed [(18)F]MPPF as a substrate for P-gp. Our microPET results showed that P-gp modulation of [(18)F]MPPF binding to 5-HT(1A) receptors can be imaged in rat hippocampus. The heterogeneous brain distribution of P-gp appeared to invalidate the use of cerebellum as a nonspecific reference region for SRTM modeling. Regional quantitation of P-gp may be necessary for accurate PET assessment of 5-HT(1A) receptor density when based on tracer uptake sensitive to P-gp modulation.
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Affiliation(s)
- Goran Laćan
- Department of Molecular and Medical Pharmacology, UCLA, Los Angeles, CA 90095-1735, USA
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Abstract
The aberrant expression and function of certain receptors in tumours and other diseased tissues make them preferable targets for molecular imaging. PET and SPECT radionuclides can be used to label specific ligands with high affinity for the target receptors. The functional information obtained from imaging these receptors can be used to better understand the systems under investigation and for diagnostic and therapeutic applications. This review discusses some of the aspects of receptor imaging with small molecule tracers by PET and SPECT and reviews some of the tracers for the receptor imaging of tumours and brain, heart and lung disorders.
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Affiliation(s)
- Aviv Hagooly
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., Campus Box 8225, St. Louis, MO 63110, USA.
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Schou M, Pike VW, Sóvágó J, Gulyás B, Gallagher PT, Dobson DR, Walter MW, Rudyk H, Farde L, Halldin C. Synthesis of 11C-labelled (R)-OHDMI and CFMME and their evaluation as candidate radioligands for imaging central norepinephrine transporters with PET. Bioorg Med Chem 2007; 15:616-25. [PMID: 17123820 DOI: 10.1016/j.bmc.2006.10.065] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2006] [Revised: 10/23/2006] [Accepted: 10/31/2006] [Indexed: 12/24/2022]
Abstract
(R)-1-(10,11-Dihydro-dibenzo[b,f]azepin-5-yl)-3-methylamino-propan-2-ol ((R)-OHDMI) and (S,S)-1-cyclopentyl-2-(5-fluoro-2-methoxy-phenyl)-1-morpholin-2-yl-ethanol (CFMME) were synthesized and found to be potent inhibitors of norepinephrine reuptake. Each was labelled efficiently in its methyl group with carbon-11 (t(1/2)=20.4 min) as a prospective radioligand for imaging brain norepinephrine transporters (NET) with positron emission tomography (PET). The uptake and distribution of radioactivity in brain following intravenous injection of each radioligand into cynomolgus monkey was examined in vivo with PET. After injection of (R)-[(11)C]OHDMI, the maximal whole brain uptake of radioactivity was very low (1.1% of injected dose; I.D.). For occipital cortex, thalamus, lower brainstem, mesencephalon and cerebellum, radioactivity ratios to striatum at 93 min after radioligand injection were 1.35, 1.35, 1.2, 1.2 and 1.0, respectively. After injection of [(11)C]CFMME, radioactivity readily entered brain (3.5% I.D.). Ratios of radioactivity to cerebellum at 93 min for thalamus, occipital cortex, region of locus coeruleus, mesencephalon and striatum were 1.35, 1.3, 1.3, 1.2 and 1.2, respectively. Radioactive metabolites in plasma were measured by radio-HPLC. (R)-[(11)C]OHDMI represented 75% of plasma radioactivity at 4 min after injection and 6% at 30 min. After injection of [(11)C]CFMME, 84% of the radioactivity in plasma represented parent at 4 min and 20% at 30 min. Since the two new hydroxylated radioligands provide only modest regional differentiation in brain uptake and form potentially troublesome lipophilic radioactive metabolites, they are concluded to be inferior to existing radioligands, such as (S,S)-[(11)C]MeNER, (S,S)-[(18)F]FMeNER-D(2) and (S,S)-[(18)F]FRB-D(4), for the study of brain NETs with PET in vivo.
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Affiliation(s)
- Magnus Schou
- Karolinska Institutet, Department of Clinical Neuroscience, Psychiatry Section, Karolinska Hospital, S-17176 Stockholm, Sweden.
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Koldobskii GI. Strategies and prospects in functionalization of tetrazoles. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2006. [DOI: 10.1134/s1070428006040014] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Schou M, Sóvágó J, Pike VW, Gulyás B, Bøgesø KP, Farde L, Halldin C. Synthesis and Positron Emission Tomography Evaluation of Three Norepinephrine Transporter Radioligands: [C-11]Desipramine, [C-11]Talopram and [C-11]Talsupram. Mol Imaging Biol 2005; 8:1-8. [PMID: 16322935 DOI: 10.1007/s11307-005-0027-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Desipramine (DMI), talopram and talsupram, three of the most potent norepinephrine transporter (NET) inhibitors reported to date, were radiolabeled in high yields and at high specific radioactivity (58-75 GBq/micromol) by the methylation of nor-precursors with [C-11]methyl triflate. The regional brain distribution of each radioligand following intravenous injection into cynomolgus monkey was examined in vivo with positron emission tomography (PET). For all three radioligands, the regional brain distribution of radioactivity was slightly heterogeneous, with higher uptake of radioactivity in the mesencephalon, thalamus and lower brainstem than in striatum. The rank order of maximal brain radioactivity (as percentage of injected dose) was [C-11]DMI (2.7%) > [C-11]talsupram (1.3%) > [C-11]talopram (0.7%). The appearance of radioactive metabolites in plasma was similar for each radioligand (75-85% of radioactivity in plasma at 45 min). These metabolites were all more polar than their parent radioligand. The data show that these radioligands are inferior to existing radioligands for the study of brain NET with PET in vivo.
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Affiliation(s)
- Magnus Schou
- Karolinska Institutet, Department of Clinical Neuroscience, Psychiatry Section, Karolinska Hospital, S-17176, Stockholm, Sweden.
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