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Bini J. The historical progression of positron emission tomography research in neuroendocrinology. Front Neuroendocrinol 2023; 70:101081. [PMID: 37423505 PMCID: PMC10530506 DOI: 10.1016/j.yfrne.2023.101081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 06/29/2023] [Accepted: 07/03/2023] [Indexed: 07/11/2023]
Abstract
The rapid and continual development of a number of radiopharmaceuticals targeting different receptor, enzyme and small molecule systems has fostered Positron Emission Tomography (PET) imaging of endocrine system actions in vivo in the human brain for several decades. PET radioligands have been developed to measure changes that are regulated by hormone action (e.g., glucose metabolism, cerebral blood flow, dopamine receptors) and actions within endocrine organs or glands such as steroids (e.g., glucocorticoids receptors), hormones (e.g., estrogen, insulin), and enzymes (e.g., aromatase). This systematic review is targeted to the neuroendocrinology community that may be interested in learning about positron emission tomography (PET) imaging for use in their research. Covering neuroendocrine PET research over the past half century, researchers and clinicians will be able to answer the question of where future research may benefit from the strengths of PET imaging.
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Affiliation(s)
- Jason Bini
- Yale PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, United States.
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2
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Kolla NJ, Bortolato M. The role of monoamine oxidase A in the neurobiology of aggressive, antisocial, and violent behavior: A tale of mice and men. Prog Neurobiol 2020; 194:101875. [PMID: 32574581 DOI: 10.1016/j.pneurobio.2020.101875] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 04/20/2020] [Accepted: 06/12/2020] [Indexed: 11/16/2022]
Abstract
Over the past two decades, research has revealed that genetic factors shape the propensity for aggressive, antisocial, and violent behavior. The best-documented gene implicated in aggression is MAOA (Monoamine oxidase A), which encodes the key enzyme for the degradation of serotonin and catecholamines. Congenital MAOA deficiency, as well as low-activity MAOA variants, has been associated with a higher risk for antisocial behavior (ASB) and violence, particularly in males with a history of child maltreatment. Indeed, the interplay between low MAOA genetic variants and early-life adversity is the best-documented gene × environment (G × E) interaction in the pathophysiology of aggression and ASB. Additional evidence indicates that low MAOA activity in the brain is strongly associated with a higher propensity for aggression; furthermore, MAOA inhibition may be one of the primary mechanisms whereby prenatal smoke exposure increases the risk of ASB. Complementary to these lines of evidence, mouse models of Maoa deficiency and G × E interactions exhibit striking similarities with clinical phenotypes, proving to be valuable tools to investigate the neurobiological mechanisms underlying antisocial and aggressive behavior. Here, we provide a comprehensive overview of the current state of the knowledge on the involvement of MAOA in aggression, as defined by preclinical and clinical evidence. In particular, we show how the convergence of human and animal research is proving helpful to our understanding of how MAOA influences antisocial and violent behavior and how it may assist in the development of preventative and therapeutic strategies for aggressive manifestations.
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Affiliation(s)
- Nathan J Kolla
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada; Centre for Addiction and Mental Health (CAMH) Research Imaging Centre, Toronto, ON, Canada; Violence Prevention Neurobiological Research Unit, CAMH, Toronto, ON, Canada; Waypoint Centre for Mental Health Care, Penetanguishene, ON, Canada; Translational Initiative on Antisocial Personality Disorder (TrIAD); Program of Research on Violence Etiology, Neurobiology, and Treatment (PReVENT).
| | - Marco Bortolato
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, UT, USA; Translational Initiative on Antisocial Personality Disorder (TrIAD); Program of Research on Violence Etiology, Neurobiology, and Treatment (PReVENT).
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Potretzke S, Robins MT, Ryabinin AE. Differential sensitivity of alcohol drinking and partner preference to a CRFR1 antagonist in prairie voles and mice. Horm Behav 2020; 120:104676. [PMID: 31927017 PMCID: PMC7117978 DOI: 10.1016/j.yhbeh.2020.104676] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/26/2019] [Accepted: 12/28/2019] [Indexed: 12/17/2022]
Abstract
Available pharmacotherapies to treat alcohol use disorder (AUD) show limited efficacy. Preclinical studies in mice and rats suggested that antagonists of the corticotropin releasing factor receptor 1 (CRFR1) could be more efficacious for such treatment. However, clinical trials with CRFR1 antagonists were not successful. While a number of potential explanations for this translational failure have been suggested, we hypothesized that the lack of success in clinical trials could be in part due to different neuroanatomical organization of the CRFR1 system in mice and rats versus humans. The CRF system in prairie voles (Microtus ochrogaster), a socially monogamous rodent species, also shows differences in organization from mice and rats. To test our hypothesis, we compared the efficacy of a potent CRFR1 antagonist, CP-376,395, to modulate alcohol drinking in male and female prairie voles versus male and female C57BL/6J mice using an almost identical 2-bottle choice drinking procedure. CP-376,375 (10 and 20 mg/kg, i.p.) significantly decreased alcohol intake (but not alcohol preference) in mice, but not prairie voles. Furthermore, administration of this antagonist (20 mg/kg, i.p.) prior to the partner preference test (PPT) decreased partner preference (PP) in male prairie voles. These findings support our hypothesis that the greater efficacy of CRFR1 antagonists to suppress alcohol consumption in mice and rats versus other mammalian species could be due to the differences in organization of the CRFR1 system between species. They further indicate that activity of the CRFR1 system is necessary for the formation of pair-bonds, but not consumption of high doses of alcohol. Overall, we suggest that testing potential pharmacotherapies should not rely only on studies in mice and rats.
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Affiliation(s)
- Sheena Potretzke
- Department of Behavioral Neuroscience, School of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
| | - Meridith T Robins
- Department of Behavioral Neuroscience, School of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
| | - Andrey E Ryabinin
- Department of Behavioral Neuroscience, School of Medicine, Oregon Health & Science University, Portland, OR 97239, USA.
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Lu Y, Choi JY, Kim SE, Lee BC. HPLC-free in situ18F-fluoromethylation of bioactive molecules by azidation and MTBD scavenging. Chem Commun (Camb) 2019; 55:11798-11801. [DOI: 10.1039/c9cc04901k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Sequential usage of azide and MTBD, which generates pure [18F]fluoromethyl tosylate and scavenges unreacted desmethyl precursors, provided an efficient HPLC-free strategy for the radio-synthesis of 18F-fluoromethylated compounds.
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Affiliation(s)
- Yingqing Lu
- Department of Nuclear Medicine
- Seoul National University College of Medicine
- Seoul National University Bundang Hospital
- Seongnam
- Republic of Korea
| | - Ji Young Choi
- Department of Nuclear Medicine
- Seoul National University College of Medicine
- Seoul National University Bundang Hospital
- Seongnam
- Republic of Korea
| | - Sang Eun Kim
- Department of Nuclear Medicine
- Seoul National University College of Medicine
- Seoul National University Bundang Hospital
- Seongnam
- Republic of Korea
| | - Byung Chul Lee
- Department of Nuclear Medicine
- Seoul National University College of Medicine
- Seoul National University Bundang Hospital
- Seongnam
- Republic of Korea
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Deussing JM, Chen A. The Corticotropin-Releasing Factor Family: Physiology of the Stress Response. Physiol Rev 2018; 98:2225-2286. [DOI: 10.1152/physrev.00042.2017] [Citation(s) in RCA: 127] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The physiological stress response is responsible for the maintenance of homeostasis in the presence of real or perceived challenges. In this function, the brain activates adaptive responses that involve numerous neural circuits and effector molecules to adapt to the current and future demands. A maladaptive stress response has been linked to the etiology of a variety of disorders, such as anxiety and mood disorders, eating disorders, and the metabolic syndrome. The neuropeptide corticotropin-releasing factor (CRF) and its relatives, the urocortins 1–3, in concert with their receptors (CRFR1, CRFR2), have emerged as central components of the physiological stress response. This central peptidergic system impinges on a broad spectrum of physiological processes that are the basis for successful adaptation and concomitantly integrate autonomic, neuroendocrine, and behavioral stress responses. This review focuses on the physiology of CRF-related peptides and their cognate receptors with the aim of providing a comprehensive up-to-date overview of the field. We describe the major molecular features covering aspects of gene expression and regulation, structural properties, and molecular interactions, as well as mechanisms of signal transduction and their surveillance. In addition, we discuss the large body of published experimental studies focusing on state-of-the-art genetic approaches with high temporal and spatial precision, which collectively aimed to dissect the contribution of CRF-related ligands and receptors to different levels of the stress response. We discuss the controversies in the field and unravel knowledge gaps that might pave the way for future research directions and open up novel opportunities for therapeutic intervention.
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Affiliation(s)
- Jan M. Deussing
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany; and Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Alon Chen
- Department of Stress Neurobiology and Neurogenetics, Max Planck Institute of Psychiatry, Munich, Germany; and Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
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Hebeisen P, Weiss U, Alker A, Kuhn B, Müller K, Wang F, Surya Prakash GK. Molecular Structure and Crystal Packing of Monofluoromethoxyarenes. European J Org Chem 2018. [DOI: 10.1002/ejoc.201701758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Paul Hebeisen
- Pharmaceutical Research & Early Development; Roche Innovation Center Basel; F. Hoffmann-La Roche AG; Grenzacherstrasse 124 4070 Basel Switzerland
| | - Urs Weiss
- Pharmaceutical Research & Early Development; Roche Innovation Center Basel; F. Hoffmann-La Roche AG; Grenzacherstrasse 124 4070 Basel Switzerland
| | - André Alker
- Pharmaceutical Research & Early Development; Roche Innovation Center Basel; F. Hoffmann-La Roche AG; Grenzacherstrasse 124 4070 Basel Switzerland
| | - Bernd Kuhn
- Pharmaceutical Research & Early Development; Roche Innovation Center Basel; F. Hoffmann-La Roche AG; Grenzacherstrasse 124 4070 Basel Switzerland
| | - Klaus Müller
- Laboratorium für Organische Chemie; ETH Zürich; Vladimir-Prelog-Weg 3 8093 Zürich Switzerland
| | - Fang Wang
- Loker Hydrocarbon Research Institute; Department of Chemistry; University of Southern California; 1661 Los Angeles CA 90089- USA
| | - G. K. Surya Prakash
- Loker Hydrocarbon Research Institute; Department of Chemistry; University of Southern California; 1661 Los Angeles CA 90089- USA
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Tollefson S, Himes M, Narendran R. Imaging corticotropin-releasing-factor and nociceptin in addiction and PTSD models. Int Rev Psychiatry 2017; 29:567-579. [PMID: 29231765 DOI: 10.1080/09540261.2017.1404445] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Addiction is composed of three phases: intoxication, withdrawal, and craving. Negative reinforcement, strengthening a behaviour by removing an aversive stimulus, has been associated with the withdrawal phase. An imbalance of neurotransmitters within the brain's stress (nociceptin, neuropeptide Y) and anti-stress (CRF, norepinephrine, etc.) system is attributed to negatively reinforced compulsive behaviours associated with relapse. Similarly, post-traumatic stress disorder is characterized by an overactive stress system. In a PTSD mouse model, rodents exhibited impaired cued-fear memory consolidation when nociceptin transmission was blocked. Furthermore, a single-nucleotide polymorphism has been identified between women diagnosed with PTSD and the severity of PTSD symptoms, suggesting a genetic basis. Therefore, it is critical to understand the functions and interactions between the brain's stress and anti-stress neurotransmitters, specifically nociceptin. This paper will examine the hypothalamic-pituitary-adrenocortical axis, evaluate the functions of corticotropin-releasing-factor and nociceptin, discuss nociceptin's role as an anxiolytic or anxiogenic, and discuss PET-imaging studies-all of which targeted nociceptin receptors (NOP-R). Finally, the discussion of pharmacological interventions will be proposed as preventative or therapeutic treatments for those suffering from PTSD and substance-use disorders.
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Affiliation(s)
- Savannah Tollefson
- a Department of Radiology , University of Pittsburgh School of Medicine , Pittsburgh , PA , USA
| | - Michael Himes
- a Department of Radiology , University of Pittsburgh School of Medicine , Pittsburgh , PA , USA
| | - Rajesh Narendran
- a Department of Radiology , University of Pittsburgh School of Medicine , Pittsburgh , PA , USA
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Spierling SR, Zorrilla EP. Don't stress about CRF: assessing the translational failures of CRF 1antagonists. Psychopharmacology (Berl) 2017; 234:1467-1481. [PMID: 28265716 PMCID: PMC5420464 DOI: 10.1007/s00213-017-4556-2] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Accepted: 01/27/2017] [Indexed: 02/06/2023]
Abstract
BACKGROUND Dr. Athina Markou sought treatments for a common neural substrate shared by depression and drug dependence. Antagonists of corticotropin-releasing factor (CRF) receptors, a target of interest to her, have not reached the clinic despite strong preclinical rationale and sustained translational efforts. METHODS We explore potential causes for the failure of CRF1 antagonists and review recent findings concerning CRF-CRF1 systems in psychopathology. RESULTS Potential causes for negative outcomes include (1) poor safety and efficacy of initial drug candidates due to bad pharmacokinetic and physicochemical properties, (2) specificity problems with preclinical screens, (3) the acute nature of screens vs. late-presenting patients, (4) positive preclinical results limited to certain models and conditions with dynamic CRF-CRF1 activation not homologous to tested patients, (5) repeated CRF1 activation-induced plasticity that reduces the importance of ongoing CRF1 agonist stimulation, and (6) therapeutic silencing which may need to address CRF2 receptor or CRF-binding protein molecules, constitutive CRF1 activity, or molecules that influence agonist-independent activity or to target structural regions other than the allosteric site bound by all drug candidates. We describe potential markers of activation towards individualized treatment, human genetic, and functional data that still implicate CRF1 systems in emotional disturbance, sex differences, and suggestive clinical findings for CRF1 antagonists in food craving and CRF-driven HPA-axis overactivation. CONCLUSION The therapeutic scope of selective CRF1 antagonists now appears narrower than had been hoped. Yet, much remains to be learned about CRF's role in the neurobiology of dysphoria and addiction and the potential for novel anti-CRF therapies therein.
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Affiliation(s)
- Samantha R Spierling
- Committee on the Neurobiology of Addictive Disorders, SP30-2400, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA, 92037, USA.
| | - Eric P Zorrilla
- Committee on the Neurobiology of Addictive Disorders, SP30-2400, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA, 92037, USA.
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van der Born D, Pees A, Poot AJ, Orru RVA, Windhorst AD, Vugts DJ. Fluorine-18 labelled building blocks for PET tracer synthesis. Chem Soc Rev 2017; 46:4709-4773. [DOI: 10.1039/c6cs00492j] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This review presents a comprehensive overview of the synthesis and application of fluorine-18 labelled building blocks since 2010.
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Affiliation(s)
- Dion van der Born
- Department of Radiology & Nuclear Medicine
- VU University Medical Center
- 1081 HV Amsterdam
- The Netherlands
| | - Anna Pees
- Department of Radiology & Nuclear Medicine
- VU University Medical Center
- 1081 HV Amsterdam
- The Netherlands
| | - Alex J. Poot
- Department of Radiology & Nuclear Medicine
- VU University Medical Center
- 1081 HV Amsterdam
- The Netherlands
| | - Romano V. A. Orru
- Department of Chemistry and Pharmaceutical Sciences and Amsterdam Institute for Molecules
- Medicines & Systems (AIMMS)
- VU University Amsterdam
- Amsterdam
- The Netherlands
| | - Albert D. Windhorst
- Department of Radiology & Nuclear Medicine
- VU University Medical Center
- 1081 HV Amsterdam
- The Netherlands
| | - Danielle J. Vugts
- Department of Radiology & Nuclear Medicine
- VU University Medical Center
- 1081 HV Amsterdam
- The Netherlands
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Cheng G, Werner TJ, Newberg A, Alavi A. Failed PET Application Attempts in the Past, Can We Avoid Them in the Future? Mol Imaging Biol 2016; 18:797-802. [DOI: 10.1007/s11307-016-1017-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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11
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The CRF System as a Therapeutic Target for Neuropsychiatric Disorders. Trends Pharmacol Sci 2016; 37:1045-1054. [PMID: 27717506 DOI: 10.1016/j.tips.2016.09.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 09/07/2016] [Accepted: 09/08/2016] [Indexed: 11/21/2022]
Abstract
The major neuropsychiatric disorders are devastating illnesses that are only modestly responsive to treatment. Improving the treatment of these conditions will require innovative new strategies that depart from previously focused-on pharmacological mechanisms. Considerable preclinical and clinical data indicate corticotropin-releasing factor (CRF) signaling as a target for new psychotropic drug development. Here we review alterations in the CRF system reported in several psychiatric conditions. We also examine the preclinical work that has dissected the distinctive roles of CRF receptors in specific circuits relevant to these disorders. We further describe the clinical trials of CRF1 receptor antagonists that have been conducted. Although these clinical trials have thus far met with limited therapeutic success, the unfolding complexity of the CRF system promises many future directions for studying its role in the etiology and treatment of neuropsychiatric conditions.
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Stehouwer JS, Bourke CH, Owens MJ, Voll RJ, Kilts CD, Goodman MM. Synthesis, binding affinity, radiolabeling, and microPET evaluation of 4-(2-substituted-4-substituted)-8-(dialkylamino)-6-methyl-1-substituted-3,4-dihydropyrido[2,3-b]pyrazin-2(1H)-ones as ligands for brain corticotropin-releasing factor type-1 (CRF1) receptors. Bioorg Med Chem Lett 2015; 25:5111-4. [PMID: 26456805 DOI: 10.1016/j.bmcl.2015.10.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 10/01/2015] [Accepted: 10/05/2015] [Indexed: 12/28/2022]
Abstract
Compounds 1-14 were synthesized in a search for high-affinity CRF1 receptor ligands that could be radiolabeled with (11)C or (18)F for use as positron emission tomography (PET) radiotracers. Derivatives of 2 were developed which contained amide N-fluoroalkyl substituents. Compounds [(18)F]24 and [(18)F]25 were found to have appropriate lipophilicities of logP7.4=2.2 but microPET imaging with [(18)F]25 demonstrated limited brain uptake.
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Affiliation(s)
- Jeffrey S Stehouwer
- Center for Systems Imaging, Department of Radiology and Imaging Sciences, Emory University, WWHC 209, 1841 Clifton Rd NE, Atlanta, GA 30329, USA.
| | - Chase H Bourke
- Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA, USA
| | - Michael J Owens
- Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA, USA
| | - Ronald J Voll
- Center for Systems Imaging, Department of Radiology and Imaging Sciences, Emory University, WWHC 209, 1841 Clifton Rd NE, Atlanta, GA 30329, USA
| | - Clinton D Kilts
- Psychiatric Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Mark M Goodman
- Center for Systems Imaging, Department of Radiology and Imaging Sciences, Emory University, WWHC 209, 1841 Clifton Rd NE, Atlanta, GA 30329, USA; Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA, USA
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13
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Stehouwer JS, Birnbaum MS, Voll RJ, Owens MJ, Plott SJ, Bourke CH, Wassef MA, Kilts CD, Goodman MM. Synthesis, F-18 radiolabeling, and microPET evaluation of 3-(2,4-dichlorophenyl)-N-alkyl-N-fluoroalkyl-2,5-dimethylpyrazolo[1,5-a]pyrimidin-7-amines as ligands of the corticotropin-releasing factor type-1 (CRF1) receptor. Bioorg Med Chem 2015; 23:4286-4302. [PMID: 26145817 DOI: 10.1016/j.bmc.2015.06.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 06/04/2015] [Accepted: 06/12/2015] [Indexed: 12/28/2022]
Abstract
A series of 3-(2,4-dichlorophenyl)-N-alkyl-N-fluoroalkyl-2,5-dimethylpyrazolo[1,5-a]pyrimidin-7-amines were synthesized and evaluated as potential positron emission tomography (PET) tracers for the corticotropin-releasing factor type-1 (CRF1) receptor. Compounds 27, 28, 29, and 30 all displayed high binding affinity (⩽1.2 nM) to the CRF1 receptor when assessed by in vitro competition binding assays at 23 °C, whereas a decrease in affinity (⩾10-fold) was observed with compound 26. The logP7.4 values of [(18)F]26-[(18)F]29 were in the range of ∼2.2-2.8 and microPET evaluation of [(18)F]26-[(18)F]29 in an anesthetized male cynomolgus monkey demonstrated brain penetrance, but specific binding was not sufficient enough to differentiate regions of high CRF1 receptor density from regions of low CRF1 receptor density. Radioactivity uptake in the skull, and sphenoid bone and/or sphenoid sinus during studies with [(18)F]28, [(18)F]28-d8, and [(18)F]29 was attributed to a combination of [(18)F]fluoride generated by metabolic defluorination of the radiotracer and binding of intact radiotracer to CRF1 receptors expressed on mast cells in the bone marrow. Uptake of [(18)F]26 and [(18)F]27 in the skull and sphenoid region was rapid but then steadily washed out which suggests that this behavior was the result of binding to CRF1 receptors expressed on mast cells in the bone marrow with no contribution from [(18)F]fluoride.
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Affiliation(s)
- Jeffrey S Stehouwer
- Center for Systems Imaging, Department of Radiology and Imaging Sciences, Emory University, WWHC 209, 1841 Clifton Rd NE, Atlanta, GA 30329, USA.
| | - Matthew S Birnbaum
- Center for Systems Imaging, Department of Radiology and Imaging Sciences, Emory University, WWHC 209, 1841 Clifton Rd NE, Atlanta, GA 30329, USA
| | - Ronald J Voll
- Center for Systems Imaging, Department of Radiology and Imaging Sciences, Emory University, WWHC 209, 1841 Clifton Rd NE, Atlanta, GA 30329, USA
| | - Michael J Owens
- Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA, USA
| | - Susan J Plott
- Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA, USA
| | - Chase H Bourke
- Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA, USA
| | - Michael A Wassef
- Center for Systems Imaging, Department of Radiology and Imaging Sciences, Emory University, WWHC 209, 1841 Clifton Rd NE, Atlanta, GA 30329, USA
| | - Clinton D Kilts
- Department of Psychiatry and Behavioral Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Mark M Goodman
- Center for Systems Imaging, Department of Radiology and Imaging Sciences, Emory University, WWHC 209, 1841 Clifton Rd NE, Atlanta, GA 30329, USA; Department of Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA, USA
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