The Experts below are selected from a list of 39 Experts worldwide ranked by ideXlab platform
Ronald G Blasberg - One of the best experts on this subject based on the ideXlab platform.
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comparison of bolus and infusion methods for receptor quantitation application to 18f Cyclofoxy and positron emission tomography
Journal of Cerebral Blood Flow and Metabolism, 1993Co-Authors: Richard E Carson, Kenner C Rice, Michael A Channing, Bonnie B Dunn, Ronald G Blasberg, Robert M Cohen, Peter HerscovitchAbstract:Positron emission tomography studies with the opiate antagonist [18F]Cyclofoxy ([18F]CF) were performed in baboons. Bolus injection studies demonstrated initial uptake dependent on blood flow. The ...
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pet imaging of opiate receptor binding in human epilepsy using 18f Cyclofoxy
Epilepsy Research, 1992Co-Authors: William H Theodore, Kenner C Rice, Michael A Channing, Amy Hauck Newman, Ronald G Blasberg, Richard E Carson, Paul Andreasen, Allan Zametkin, Deborah B Leiderman, Bonnie B DunnAbstract:We used [18F]Cyclofoxy (CF), a potent opiate antagonist with affinity for mu and kappa receptors, and the Scanditronix PC1024-7B PET scanner to study 14 patients with complex partial seizures (CPS), and 14 normal controls. Epileptic foci were localized by prolonged EEG-video monitoring. EEG was recorded continuously during each scan. Immediately before CF administration, [15O]labeled water was used to measure cerebral blood flow, and showed hypoperfusion ipsilateral to the EEG focus. Blood samples (corrected for radiolabeled metabolites) and tissue time-activity data were acquired over 90 min following bolus CF injection. Anatomic regions were outlined directly on the PET images. A kinetic model was used to derive the total volume of distribution (Vt) in each brain region. Specific binding (Vs) was determined by subtracting non-specific binding (Vt) measured in a receptor-poor brain region (occipital cortex). Regions with high Vs included mesial temporal lobes, thalamus, basal ganglia, and frontal cortex. Individual patients appeared to have higher binding in temporal lobe ipsilateral to the EEG focus, but there was no asymmetry for the patients as a group in mean Vt or Vs i anterior mesial, posterior mesial, anterior lateral, posterior lateral temporal cortex, thalamus, basal ganglia, or, for Vt, in regions of low specific binding: occipital lobe, parietal lobe, cerebellum.
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regional brain measurement of bmax and kd with the opiate antagonist Cyclofoxy equilibrium studies in the conscious rat
Journal of Cerebral Blood Flow and Metabolism, 1991Co-Authors: R Kawai, Kenner C Rice, Bonnie B Dunn, Amy Hauck Newman, Richard E Carson, Ronald G BlasbergAbstract:Brain distribution of the opiate receptor antagonist, Cyclofoxy (CF), was evaluated at equilibrium in rats. A combination of i.v. injection and constant i.v. infusion was used to administer CF over a wide dose range (2.4–450 nmol/rat). Kinetic simulations and experimental results showed that this administration schedule accomplishes “true” tissue-blood equilibrium of CF within 60 min. To estimate the receptor-ligand binding parameters, we assumed that the CF concentration at the receptor site is identical to that in plasma water at equilibrium, and can be calculated from measured blood data after corrections for radiolabeled metabolites and plasma protein binding. This assumption was supported by CSF and plasma water measurements at equilibrium. Regional KD, Bmax, and a nonspecific tissue binding equilibrium constant (Keq) were estimated by fitting the tissue and plasma water concentrations to a single receptor model; the estimated values were 1.4–2.9 nM, 15–74 pmol/g of tissue, and 5.2–8.0, respectively....
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kinetic analysis of transport and opioid receptor binding of 3h Cyclofoxy in rat brain in vivo implications for human studies
Journal of Cerebral Blood Flow and Metabolism, 1991Co-Authors: Yasufumi Sawada, Kenner C Rice, R Kawai, Clifford S Patlak, Mary Mcmanaway, Hideo Otsuki, Ronald G BlasbergAbstract:(3H)Cyclofoxy (CF: 17-cyclopropylmethyl-3,14-dihydroxy-4,5-alpha-epoxy-6-beta-fluoromorp hinan) is an opioid antagonist with affinity to both mu and kappa subtypes that was synthesized for quantitative evaluation of opioid receptor binding in vivo. Two sets of experiments in rats were analyzed. The first involved determining the metabolite-corrected blood concentration and tissue distribution of CF in brain 1 to 60 min after i.v. bolus injection. The second involved measuring brain washout for 15 to 120 s following intracarotid artery injection of CF. A physiologically based model and a classical compartmental pharmacokinetic model were compared. The models included different assumptions for transport across the blood-brain barrier (BBB); estimates of nonspecific tissue binding and specific binding to a single opiate receptor site were found to be essentially the same with both models. The nonspecific binding equilibrium constant varied modestly in different brain structures (Keq = 3-9), whereas the binding potential (BP) varied over a much broader range (BP = 0.6-32). In vivo estimates of the opioid receptor dissociation constant were similar for different brain structures (KD = 2.1-5.2 nM), whereas the apparent receptor density (Bmax) varied between 1 (cerebellum) and 78 (thalamus) pmol/g of brain. The receptor dissociation rate constants in cerebrum (k4 = 0.08-0.16 min-1; koff =more » 0.16-0.23 min-1) and brain vascular permeability (PS = 1.3-3.4 ml/min/g) are sufficiently high to achieve equilibrium conditions within a reasonable period of time. Graphical analysis of the data is inappropriate due to the high tissue-loss rate constant for CF in brain. From these findings, CF should be a very useful opioid receptor ligand for the estimation of the receptor binding parameters in human subjects using (18F)CF and positron emission tomography.« less
Kenner C Rice - One of the best experts on this subject based on the ideXlab platform.
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opioid receptor imaging with positron emission tomography and 18 f Cyclofoxy in long term methadone treated former heroin addicts
Journal of Pharmacology and Experimental Therapeutics, 2000Co-Authors: Mitchel A Kling, Kenner C Rice, Richard E Carson, Peter Herscovitch, Lisa Borg, Alan J Zametkin, John A Matochik, James H Schluger, William C Eckelman, Mary Jeanne KreekAbstract:Stabilized methadone-maintained former heroin addicts (MTPs) treated with effective doses of methadone have markedly reduced drug craving; reduction or elimination of heroin use; normalized stress-responsive hypothalamic-pituitary-adrenal, reproductive, and gastrointestinal function; and marked improvement in immune function and normal responses to pain, all of which are physiological indices modulated in part by endogenous and exogenous opioids directed at the mu and, in some cases, the kappa-opioid systems. This study was performed to explore opioid receptor binding in MTPs. Fourteen normal, healthy volunteers and 14 long-term MTPs in treatment for 2 to 27 years and receiving 30 to 90 mg/day of methadone were studied with positron emission tomography using tracer amounts of [(18)F]Cyclofoxy, an opioid antagonist that labels mu and kappa opioid receptors. Imaging was performed in the morning, 22 h after the last dose of methadone in patients, and concurrent plasma levels of methadone were determined. Five brain regions of specific interest for addiction and pain research (thalamus, amygdala, caudate, anterior cingulate cortex, and putamen) were among the six regions of highest [(18)F]Cyclofoxy binding. Specific binding of [(18)F]Cyclofoxy was lower by 19 to 32% in these regions in MTPs compared with those in normal volunteers. The degree to which specific binding was lower in caudate and putamen correlated with methadone plasma levels (P <.01 and P <.05, respectively), suggesting that these lower levels of binding may be related to receptor occupancy with methadone and that significant numbers of opioid receptors may be available to function in their normal physiological roles.
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comparison of bolus and infusion methods for receptor quantitation application to 18f Cyclofoxy and positron emission tomography
Journal of Cerebral Blood Flow and Metabolism, 1993Co-Authors: Richard E Carson, Kenner C Rice, Michael A Channing, Bonnie B Dunn, Ronald G Blasberg, Robert M Cohen, Peter HerscovitchAbstract:Positron emission tomography studies with the opiate antagonist [18F]Cyclofoxy ([18F]CF) were performed in baboons. Bolus injection studies demonstrated initial uptake dependent on blood flow. The ...
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pet imaging of opiate receptor binding in human epilepsy using 18f Cyclofoxy
Epilepsy Research, 1992Co-Authors: William H Theodore, Kenner C Rice, Michael A Channing, Amy Hauck Newman, Ronald G Blasberg, Richard E Carson, Paul Andreasen, Allan Zametkin, Deborah B Leiderman, Bonnie B DunnAbstract:We used [18F]Cyclofoxy (CF), a potent opiate antagonist with affinity for mu and kappa receptors, and the Scanditronix PC1024-7B PET scanner to study 14 patients with complex partial seizures (CPS), and 14 normal controls. Epileptic foci were localized by prolonged EEG-video monitoring. EEG was recorded continuously during each scan. Immediately before CF administration, [15O]labeled water was used to measure cerebral blood flow, and showed hypoperfusion ipsilateral to the EEG focus. Blood samples (corrected for radiolabeled metabolites) and tissue time-activity data were acquired over 90 min following bolus CF injection. Anatomic regions were outlined directly on the PET images. A kinetic model was used to derive the total volume of distribution (Vt) in each brain region. Specific binding (Vs) was determined by subtracting non-specific binding (Vt) measured in a receptor-poor brain region (occipital cortex). Regions with high Vs included mesial temporal lobes, thalamus, basal ganglia, and frontal cortex. Individual patients appeared to have higher binding in temporal lobe ipsilateral to the EEG focus, but there was no asymmetry for the patients as a group in mean Vt or Vs i anterior mesial, posterior mesial, anterior lateral, posterior lateral temporal cortex, thalamus, basal ganglia, or, for Vt, in regions of low specific binding: occipital lobe, parietal lobe, cerebellum.
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regional brain measurement of bmax and kd with the opiate antagonist Cyclofoxy equilibrium studies in the conscious rat
Journal of Cerebral Blood Flow and Metabolism, 1991Co-Authors: R Kawai, Kenner C Rice, Bonnie B Dunn, Amy Hauck Newman, Richard E Carson, Ronald G BlasbergAbstract:Brain distribution of the opiate receptor antagonist, Cyclofoxy (CF), was evaluated at equilibrium in rats. A combination of i.v. injection and constant i.v. infusion was used to administer CF over a wide dose range (2.4–450 nmol/rat). Kinetic simulations and experimental results showed that this administration schedule accomplishes “true” tissue-blood equilibrium of CF within 60 min. To estimate the receptor-ligand binding parameters, we assumed that the CF concentration at the receptor site is identical to that in plasma water at equilibrium, and can be calculated from measured blood data after corrections for radiolabeled metabolites and plasma protein binding. This assumption was supported by CSF and plasma water measurements at equilibrium. Regional KD, Bmax, and a nonspecific tissue binding equilibrium constant (Keq) were estimated by fitting the tissue and plasma water concentrations to a single receptor model; the estimated values were 1.4–2.9 nM, 15–74 pmol/g of tissue, and 5.2–8.0, respectively....
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interaction of β funaltrexamine with 3h Cyclofoxy binding in rat brain further evidence that β fna alkylates the opioid receptor complex
Synapse, 1991Co-Authors: Richard B Rothman, Victor Bykov, Kenner C Rice, Artin Mahboubi, Joseph B Long, Qi Jiang, Frank Porreca, Brain R De Costa, Arthus E Jacobson, John W. HoladayAbstract:beta-Funaltrexamine (beta-FNA) is an alkylating derivative of naltrexone. In addition to acting as an irreversible inhibitor of mu-receptor-mediated physiological effects, intracerebroventricular (i.c.v.) administration of beta-FNA to rat attenuates the ability of selective delta receptor antagonists and naloxone to reverse delta receptor-mediated effects. Moreover, recent work demonstrated that i.c.v. administration of beta-FNA alters the conformation of the opioid receptor complex, as inferred by a decrease in the Bmax of the lower affinity [3H][D-ala2,D-leu5]enkephalin binding site. Consistent with the decreased potency of naloxone as an inhibitor of delta receptor mediated effects, beta-FNA doubled the naloxone IC50 for displacing [3H][D-ala2,D-leu5]enkephalin from its lower affinity binding site. These data collectively support the hypothesis that the opioid receptor complex postulated to mediate mu-delta interactions in vivo is identical to the opioid receptor complex as defined by vitro ligand binding studies. A direct prediction of this hypothesis is that beta-FNA should increase the Kd of antagonists for the mu binding site (mu cx) of the receptor complex. The data reported in this paper demonstrate that beta-FNA doubled the IC50 of the potent narcotic antagonist, 6-desoxy-6 beta-fluoronaltrexone (Cyclofoxy) for displacing [3H][D-ala2,D-leu5]enkephalin from its lower affinity binding site, and doubled the Kd of [3H]Cyclofoxy for its mu binding site, providing additional data that the mu binding site labeled by [3H]Cyclofoxy is the mu binding site of the opioid receptor complex. beta-FNA also altered the kappa binding site labeled by [3H]Cyclofoxy, and when administered intrathecally to mice, beta-FNA produced a longlasting antinociception in the acetic acid writhing test.
Richard E Carson - One of the best experts on this subject based on the ideXlab platform.
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opioid receptor imaging with positron emission tomography and 18 f Cyclofoxy in long term methadone treated former heroin addicts
Journal of Pharmacology and Experimental Therapeutics, 2000Co-Authors: Mitchel A Kling, Kenner C Rice, Richard E Carson, Peter Herscovitch, Lisa Borg, Alan J Zametkin, John A Matochik, James H Schluger, William C Eckelman, Mary Jeanne KreekAbstract:Stabilized methadone-maintained former heroin addicts (MTPs) treated with effective doses of methadone have markedly reduced drug craving; reduction or elimination of heroin use; normalized stress-responsive hypothalamic-pituitary-adrenal, reproductive, and gastrointestinal function; and marked improvement in immune function and normal responses to pain, all of which are physiological indices modulated in part by endogenous and exogenous opioids directed at the mu and, in some cases, the kappa-opioid systems. This study was performed to explore opioid receptor binding in MTPs. Fourteen normal, healthy volunteers and 14 long-term MTPs in treatment for 2 to 27 years and receiving 30 to 90 mg/day of methadone were studied with positron emission tomography using tracer amounts of [(18)F]Cyclofoxy, an opioid antagonist that labels mu and kappa opioid receptors. Imaging was performed in the morning, 22 h after the last dose of methadone in patients, and concurrent plasma levels of methadone were determined. Five brain regions of specific interest for addiction and pain research (thalamus, amygdala, caudate, anterior cingulate cortex, and putamen) were among the six regions of highest [(18)F]Cyclofoxy binding. Specific binding of [(18)F]Cyclofoxy was lower by 19 to 32% in these regions in MTPs compared with those in normal volunteers. The degree to which specific binding was lower in caudate and putamen correlated with methadone plasma levels (P <.01 and P <.05, respectively), suggesting that these lower levels of binding may be related to receptor occupancy with methadone and that significant numbers of opioid receptors may be available to function in their normal physiological roles.
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opiate receptor avidity is increased in rhesus monkeys following unilateral optic tract lesion combined with transections of corpus callosum and hippocampal and anterior commissures
Brain Research, 2000Co-Authors: Robert M Cohen, Richard E Carson, Richard C Saunders, Doris J DoudetAbstract:Abstract Opiate receptor avidity (Bmax′/KD) was measured in four rhesus monkeys following unilateral lesioning of the optic tract combined with transection of the corpus callosum and the hippocampal and anterior commissures depriving one hemisphere of visual input (Tract and Split), two animals with transection of commissures only (Split), and nine healthy monkeys with positron emission tomography (PET) and 6-deoxy-6-β-[18F]fluoronaltrexone (Cyclofoxy, CF), a μ- and κ-opiate receptor antagonist. Opiate receptor avidity was found to be significantly higher in the Tract and Split animals, only, bilaterally, throughout the lateral cortex and in the cingulate and posterior putamen (41–117%). Ipsilateral changes were consistently greater than those contralateral, but this asymmetry was of statistical significance only in the parietal and occipital cortices. Cyclofoxy avidity was decreased in the medial cortex of both the Tract and Split and Split animals (∼25%). The results suggest that opiate pathways undergo extensive alteration in response to changes in brain functional activities brought about through hemispheric visual deprivation.
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comparison of bolus and infusion methods for receptor quantitation application to 18f Cyclofoxy and positron emission tomography
Journal of Cerebral Blood Flow and Metabolism, 1993Co-Authors: Richard E Carson, Kenner C Rice, Michael A Channing, Bonnie B Dunn, Ronald G Blasberg, Robert M Cohen, Peter HerscovitchAbstract:Positron emission tomography studies with the opiate antagonist [18F]Cyclofoxy ([18F]CF) were performed in baboons. Bolus injection studies demonstrated initial uptake dependent on blood flow. The ...
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pet imaging of opiate receptor binding in human epilepsy using 18f Cyclofoxy
Epilepsy Research, 1992Co-Authors: William H Theodore, Kenner C Rice, Michael A Channing, Amy Hauck Newman, Ronald G Blasberg, Richard E Carson, Paul Andreasen, Allan Zametkin, Deborah B Leiderman, Bonnie B DunnAbstract:We used [18F]Cyclofoxy (CF), a potent opiate antagonist with affinity for mu and kappa receptors, and the Scanditronix PC1024-7B PET scanner to study 14 patients with complex partial seizures (CPS), and 14 normal controls. Epileptic foci were localized by prolonged EEG-video monitoring. EEG was recorded continuously during each scan. Immediately before CF administration, [15O]labeled water was used to measure cerebral blood flow, and showed hypoperfusion ipsilateral to the EEG focus. Blood samples (corrected for radiolabeled metabolites) and tissue time-activity data were acquired over 90 min following bolus CF injection. Anatomic regions were outlined directly on the PET images. A kinetic model was used to derive the total volume of distribution (Vt) in each brain region. Specific binding (Vs) was determined by subtracting non-specific binding (Vt) measured in a receptor-poor brain region (occipital cortex). Regions with high Vs included mesial temporal lobes, thalamus, basal ganglia, and frontal cortex. Individual patients appeared to have higher binding in temporal lobe ipsilateral to the EEG focus, but there was no asymmetry for the patients as a group in mean Vt or Vs i anterior mesial, posterior mesial, anterior lateral, posterior lateral temporal cortex, thalamus, basal ganglia, or, for Vt, in regions of low specific binding: occipital lobe, parietal lobe, cerebellum.
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regional brain measurement of bmax and kd with the opiate antagonist Cyclofoxy equilibrium studies in the conscious rat
Journal of Cerebral Blood Flow and Metabolism, 1991Co-Authors: R Kawai, Kenner C Rice, Bonnie B Dunn, Amy Hauck Newman, Richard E Carson, Ronald G BlasbergAbstract:Brain distribution of the opiate receptor antagonist, Cyclofoxy (CF), was evaluated at equilibrium in rats. A combination of i.v. injection and constant i.v. infusion was used to administer CF over a wide dose range (2.4–450 nmol/rat). Kinetic simulations and experimental results showed that this administration schedule accomplishes “true” tissue-blood equilibrium of CF within 60 min. To estimate the receptor-ligand binding parameters, we assumed that the CF concentration at the receptor site is identical to that in plasma water at equilibrium, and can be calculated from measured blood data after corrections for radiolabeled metabolites and plasma protein binding. This assumption was supported by CSF and plasma water measurements at equilibrium. Regional KD, Bmax, and a nonspecific tissue binding equilibrium constant (Keq) were estimated by fitting the tissue and plasma water concentrations to a single receptor model; the estimated values were 1.4–2.9 nM, 15–74 pmol/g of tissue, and 5.2–8.0, respectively....
Bonnie B Dunn - One of the best experts on this subject based on the ideXlab platform.
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comparison of bolus and infusion methods for receptor quantitation application to 18f Cyclofoxy and positron emission tomography
Journal of Cerebral Blood Flow and Metabolism, 1993Co-Authors: Richard E Carson, Kenner C Rice, Michael A Channing, Bonnie B Dunn, Ronald G Blasberg, Robert M Cohen, Peter HerscovitchAbstract:Positron emission tomography studies with the opiate antagonist [18F]Cyclofoxy ([18F]CF) were performed in baboons. Bolus injection studies demonstrated initial uptake dependent on blood flow. The ...
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pet imaging of opiate receptor binding in human epilepsy using 18f Cyclofoxy
Epilepsy Research, 1992Co-Authors: William H Theodore, Kenner C Rice, Michael A Channing, Amy Hauck Newman, Ronald G Blasberg, Richard E Carson, Paul Andreasen, Allan Zametkin, Deborah B Leiderman, Bonnie B DunnAbstract:We used [18F]Cyclofoxy (CF), a potent opiate antagonist with affinity for mu and kappa receptors, and the Scanditronix PC1024-7B PET scanner to study 14 patients with complex partial seizures (CPS), and 14 normal controls. Epileptic foci were localized by prolonged EEG-video monitoring. EEG was recorded continuously during each scan. Immediately before CF administration, [15O]labeled water was used to measure cerebral blood flow, and showed hypoperfusion ipsilateral to the EEG focus. Blood samples (corrected for radiolabeled metabolites) and tissue time-activity data were acquired over 90 min following bolus CF injection. Anatomic regions were outlined directly on the PET images. A kinetic model was used to derive the total volume of distribution (Vt) in each brain region. Specific binding (Vs) was determined by subtracting non-specific binding (Vt) measured in a receptor-poor brain region (occipital cortex). Regions with high Vs included mesial temporal lobes, thalamus, basal ganglia, and frontal cortex. Individual patients appeared to have higher binding in temporal lobe ipsilateral to the EEG focus, but there was no asymmetry for the patients as a group in mean Vt or Vs i anterior mesial, posterior mesial, anterior lateral, posterior lateral temporal cortex, thalamus, basal ganglia, or, for Vt, in regions of low specific binding: occipital lobe, parietal lobe, cerebellum.
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regional brain measurement of bmax and kd with the opiate antagonist Cyclofoxy equilibrium studies in the conscious rat
Journal of Cerebral Blood Flow and Metabolism, 1991Co-Authors: R Kawai, Kenner C Rice, Bonnie B Dunn, Amy Hauck Newman, Richard E Carson, Ronald G BlasbergAbstract:Brain distribution of the opiate receptor antagonist, Cyclofoxy (CF), was evaluated at equilibrium in rats. A combination of i.v. injection and constant i.v. infusion was used to administer CF over a wide dose range (2.4–450 nmol/rat). Kinetic simulations and experimental results showed that this administration schedule accomplishes “true” tissue-blood equilibrium of CF within 60 min. To estimate the receptor-ligand binding parameters, we assumed that the CF concentration at the receptor site is identical to that in plasma water at equilibrium, and can be calculated from measured blood data after corrections for radiolabeled metabolites and plasma protein binding. This assumption was supported by CSF and plasma water measurements at equilibrium. Regional KD, Bmax, and a nonspecific tissue binding equilibrium constant (Keq) were estimated by fitting the tissue and plasma water concentrations to a single receptor model; the estimated values were 1.4–2.9 nM, 15–74 pmol/g of tissue, and 5.2–8.0, respectively....
Peter Herscovitch - One of the best experts on this subject based on the ideXlab platform.
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opioid receptor imaging with positron emission tomography and 18 f Cyclofoxy in long term methadone treated former heroin addicts
Journal of Pharmacology and Experimental Therapeutics, 2000Co-Authors: Mitchel A Kling, Kenner C Rice, Richard E Carson, Peter Herscovitch, Lisa Borg, Alan J Zametkin, John A Matochik, James H Schluger, William C Eckelman, Mary Jeanne KreekAbstract:Stabilized methadone-maintained former heroin addicts (MTPs) treated with effective doses of methadone have markedly reduced drug craving; reduction or elimination of heroin use; normalized stress-responsive hypothalamic-pituitary-adrenal, reproductive, and gastrointestinal function; and marked improvement in immune function and normal responses to pain, all of which are physiological indices modulated in part by endogenous and exogenous opioids directed at the mu and, in some cases, the kappa-opioid systems. This study was performed to explore opioid receptor binding in MTPs. Fourteen normal, healthy volunteers and 14 long-term MTPs in treatment for 2 to 27 years and receiving 30 to 90 mg/day of methadone were studied with positron emission tomography using tracer amounts of [(18)F]Cyclofoxy, an opioid antagonist that labels mu and kappa opioid receptors. Imaging was performed in the morning, 22 h after the last dose of methadone in patients, and concurrent plasma levels of methadone were determined. Five brain regions of specific interest for addiction and pain research (thalamus, amygdala, caudate, anterior cingulate cortex, and putamen) were among the six regions of highest [(18)F]Cyclofoxy binding. Specific binding of [(18)F]Cyclofoxy was lower by 19 to 32% in these regions in MTPs compared with those in normal volunteers. The degree to which specific binding was lower in caudate and putamen correlated with methadone plasma levels (P <.01 and P <.05, respectively), suggesting that these lower levels of binding may be related to receptor occupancy with methadone and that significant numbers of opioid receptors may be available to function in their normal physiological roles.
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comparison of bolus and infusion methods for receptor quantitation application to 18f Cyclofoxy and positron emission tomography
Journal of Cerebral Blood Flow and Metabolism, 1993Co-Authors: Richard E Carson, Kenner C Rice, Michael A Channing, Bonnie B Dunn, Ronald G Blasberg, Robert M Cohen, Peter HerscovitchAbstract:Positron emission tomography studies with the opiate antagonist [18F]Cyclofoxy ([18F]CF) were performed in baboons. Bolus injection studies demonstrated initial uptake dependent on blood flow. The ...
