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Cumming P, Scheidegger M, Dornbierer D, Palner M, Quednow BB, Martin-Soelch C. Molecular and Functional Imaging Studies of Psychedelic Drug Action in Animals and Humans. Molecules 2021; 26:2451. [PMID: 33922330 PMCID: PMC8122807 DOI: 10.3390/molecules26092451] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/15/2021] [Accepted: 04/19/2021] [Indexed: 12/19/2022] Open
Abstract
Hallucinogens are a loosely defined group of compounds including LSD, N,N-dimethyltryptamines, mescaline, psilocybin/psilocin, and 2,5-dimethoxy-4-methamphetamine (DOM), which can evoke intense visual and emotional experiences. We are witnessing a renaissance of research interest in hallucinogens, driven by increasing awareness of their psychotherapeutic potential. As such, we now present a narrative review of the literature on hallucinogen binding in vitro and ex vivo, and the various molecular imaging studies with positron emission tomography (PET) or single photon emission computer tomography (SPECT). In general, molecular imaging can depict the uptake and binding distribution of labelled hallucinogenic compounds or their congeners in the brain, as was shown in an early PET study with N1-([11C]-methyl)-2-bromo-LSD ([11C]-MBL); displacement with the non-radioactive competitor ketanserin confirmed that the majority of [11C]-MBL specific binding was to serotonin 5-HT2A receptors. However, interactions at serotonin 5HT1A and other classes of receptors and pleotropic effects on second messenger pathways may contribute to the particular experiential phenomenologies of LSD and other hallucinogenic compounds. Other salient aspects of hallucinogen action include permeability to the blood-brain barrier, the rates of metabolism and elimination, and the formation of active metabolites. Despite the maturation of radiochemistry and molecular imaging in recent years, there has been only a handful of PET or SPECT studies of radiolabeled hallucinogens, most recently using the 5-HT2A/2C agonist N-(2[11CH3O]-methoxybenzyl)-2,5-dimethoxy- 4-bromophenethylamine ([11C]Cimbi-36). In addition to PET studies of target engagement at neuroreceptors and transporters, there is a small number of studies on the effects of hallucinogenic compounds on cerebral perfusion ([15O]-water) or metabolism ([18F]-fluorodeoxyglucose/FDG). There remains considerable scope for basic imaging research on the sites of interaction of hallucinogens and their cerebrometabolic effects; we expect that hybrid imaging with PET in conjunction with functional magnetic resonance imaging (fMRI) should provide especially useful for the next phase of this research.
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Affiliation(s)
- Paul Cumming
- Department of Nuclear Medicine, Bern University Hospital, CH-3010 Bern, Switzerland
- School of Psychology and Counselling, Queensland University of Technology, Brisbane 4059, Australia
| | - Milan Scheidegger
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital of the University of Zurich, CH-8032 Zurich, Switzerland; (M.S.); (D.D.); (B.B.Q.)
| | - Dario Dornbierer
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital of the University of Zurich, CH-8032 Zurich, Switzerland; (M.S.); (D.D.); (B.B.Q.)
| | - Mikael Palner
- Odense Department of Clinical Research, University of Southern Denmark, DK-5000 Odense, Denmark;
- Department of Nuclear Medicine, Odense University Hospital, DK-5000 Odense, Denmark
- Neurobiology Research Unit, Copenhagen University Hospital, DK-2100 Copenhagen, Denmark
| | - Boris B. Quednow
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital of the University of Zurich, CH-8032 Zurich, Switzerland; (M.S.); (D.D.); (B.B.Q.)
- Neuroscience Center Zurich, University of Zurich and Swiss Federal Institute of Technology Zurich, CH-8058 Zurich, Switzerland
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Chen Y, Herrold AA, Walter AE, Reilly JL, Seidenberg PH, Nauman EA, Talavage T, Vandenbergh DJ, Slobounov SM, Breiter HC. Brain Perfusion Bridges Virtual-Reality Spatial Behavior to TPH2 Genotype for Head Acceleration Events. J Neurotrauma 2021; 38:1368-1376. [PMID: 33413020 DOI: 10.1089/neu.2020.7016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Neuroimaging demonstrates that athletes of collision sports can suffer significant changes to their brain in the absence of concussion, attributable to head acceleration event (HAE) exposure. In a sample of 24 male Division I collegiate football players, we examine the relationships between tryptophan hydroxylase 2 (TPH2), a gene involved in neurovascular function, regional cerebral blood flow (rCBF) measured by arterial spin labeling, and virtual reality (VR) motor performance, both pre-season and across a single football season. For the pre-season, TPH2 T-carriers showed lower rCBF in two left hemisphere foci (fusiform gyrus/thalamus/hippocampus and cerebellum) in association with higher (better performance) VR Reaction Time, a dynamic measure of sensory-motor reactivity and efficiency of visual-spatial processing. For TPH2 CC homozygotes, higher pre-season rCBF in these foci was associated with better performance on VR Reaction Time. A similar relationship was observed across the season, where TPH2 T-carriers showed improved VR Reaction Time associated with decreases in rCBF in the right hippocampus/amygdala, left middle temporal lobe, and left insula/putamen/pallidum. In contrast, TPH2 CC homozygotes showed improved VR Reaction Time associated with increases in rCBF in the same three clusters. These findings show that TPH2 T-carriers have an abnormal relationship between rCBF and the efficiency of visual-spatial processing that is exacerbated after a season of high-impact sports in the absence of diagnosable concussion. Such gene-environment interactions associated with behavioral changes after exposure to repetitive HAEs have been unrecognized with current clinical analytical tools and warrant further investigation. Our results demonstrate the importance of considering neurovascular factors along with traumatic axonal injury to study long-term effects of repetitive HAEs.
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Affiliation(s)
- Yufen Chen
- Center for Translational Imaging, Department of Radiology, Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Amy A Herrold
- Edward Hines Jr., VA Hospital, Research Service, Hines, Illinois, USA.,Warren Wright Adolescent Center, Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Alexa E Walter
- Department of Kinesiology, Pennsylvania State University, University Park, Pennsylvania, USA
| | - James L Reilly
- Warren Wright Adolescent Center, Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
| | - Peter H Seidenberg
- Departments of Orthopedics and Rehabilitation and Family and Community Medicine, College of Medicine, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Eric A Nauman
- School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana, USA.,Department of Basic Medical Sciences, Purdue University, West Lafayette, Indiana, USA.,Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, USA
| | - Thomas Talavage
- School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana, USA.,Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, USA
| | - David J Vandenbergh
- Department of Biobehavioral Health, Pennsylvania State University, University Park, Pennsylvania, USA.,Penn State Neuroscience Institute, Pennsylvania State University, University Park, Pennsylvania, USA.,Molecular, Cellular, and Integrative Biosciences Program, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Semyon M Slobounov
- Department of Kinesiology, Pennsylvania State University, University Park, Pennsylvania, USA
| | - Hans C Breiter
- Warren Wright Adolescent Center, Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.,Laboratory of Neuroimaging and Genetics, Department of Psychiatry, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
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Kanemaru K, Diksic M. The Flinders Sensitive Line of rats, a rat model of depression, has elevated brain glucose utilization when compared to normal rats and the Flinders Resistant Line of rats. Neurochem Int 2009; 55:655-61. [DOI: 10.1016/j.neuint.2009.06.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2009] [Revised: 05/12/2009] [Accepted: 06/16/2009] [Indexed: 10/20/2022]
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4
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Skelin I, Sato H, Diksic M. Olfactory bulbectomy reduces cerebral glucose utilization: 2-[14C]deoxyglucose autoradiographic study. Brain Res Bull 2008; 76:485-92. [DOI: 10.1016/j.brainresbull.2008.01.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2007] [Revised: 01/18/2008] [Accepted: 01/22/2008] [Indexed: 10/22/2022]
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5
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Levant B, Pazdernik TL. Differential effects of ibogaine on local cerebral glucose utilization in drug-naive and morphine-dependent rats. Brain Res 2004; 1003:159-67. [PMID: 15019575 DOI: 10.1016/j.brainres.2003.12.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2003] [Indexed: 11/24/2022]
Abstract
Ibogaine, a hallucinogenic indole alkaloid, has been proposed as a treatment for addiction to opioids and other drugs of abuse. The mechanism for its putative anti-addictive effects is unknown. In this study, the effects of ibogaine on local cerebral glucose utilization (LCGU) were determined in freely moving, drug-naive, or morphine-dependent adult, male, Sprague-Dawley rats using the [(14)C]2-deoxyglucose (2-DG) method. Morphine-dependent rats were treated with increasing doses of morphine (5-25 mg/kg, s.c., b.i.d.) and then maintained at 25 mg/kg (b.i.d.) for 4-7 days. For the 2-DG procedure, rats were injected with saline or ibogaine (40 mg/kg, i.p.). 2-DG was administered 1 h after administration of ibogaine. The rate of LCGU was determined by quantitative autoradiography in 46 brain regions. In drug-naive animals, ibogaine produced significant increases in LCGU in the parietal, cingulate, and occipital cortices and cerebellum compared to controls consistent with its activity as a hallucinogen and a tremorogen. Morphine-dependent rats had only minor alterations in LCGU at the time assessed in this experiment. However, in morphine-dependent animals, ibogaine produced a global decrease in LCGU that was greatest in brain regions such as the lateral and medial preoptic areas, nucleus of the diagonal band, nucleus accumbens shell, inferior colliculus, locus coeruleus, and flocculus compared to morphine-dependent animals treated with saline. These findings indicate that ibogaine produces distinctly different effects on LCGU in drug-naive and morphine-dependent rats. This suggests that different mechanisms may underlie ibogaine's hallucinogenic and anti-addictive effects.
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Affiliation(s)
- Beth Levant
- Department of Pharmacology, Toxicology, and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160-7417, USA.
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Nobler MS, Mann JJ, Sackeim HA. Serotonin, cerebral blood flow, and cerebral metabolic rate in geriatric major depression and normal aging. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 1999; 30:250-63. [PMID: 10567727 DOI: 10.1016/s0165-0173(99)00019-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
While there is substantial evidence for abnormalities in serotonin (5-HT) neurotransmission in major depressive disorder (MDD), almost all of the findings derive from studies of young adults. Moreover, relatively little research has assessed brain 5-HT transmission in vivo. Neuroendocrine studies do not permit evaluation of a range of brain regions, but only the limited circuitry associated with hormone release. Data from autopsy studies are limited by the difficulties of assessment of the acute clinical picture before death, and by post-mortem artifacts. In vivo neuroimaging techniques overcome many of the methodological limitations of both these approaches. There is a large body of imaging data indicating regional cerebral blood flow (rCBF) and cerebral metabolic rate (rCMR) decrements both with aging and in patients with MDD. While the physiological bases for these phenomena are largely unknown, changes in brain 5-HT function may be involved. Neuroanatomical studies have revealed an intricate network of 5-HT-containing neurons within the cerebral microvasculature, with physiological evidence for serotonergic control of both rCBF and rCMR. Acute pharmacological challenges are available to probe brain 5-HT function. Such paradigms, using neuroendocrine responses as endpoints, have been of some utility in predicting outcome with antidepressant treatment. The role of 5-HT dysregulation in geriatric MDD takes on more importance given concerns regarding putative reduced efficacy of serotonin-specific reuptake inhibitors (SSRIs) in this population. If this is due to diminished responsivity of 5-HT systems, then the ability to identify antidepressant nonresponders via 5-HT challenge in combination with neuroimaging measures may have important clinical utility.
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Affiliation(s)
- M S Nobler
- Departments of Biological Psychiatry and Neuroscience, New York State Psychiatric Institute, 1051 Riverside Drive, Unit 126, New York, NY, USA.
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7
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Porrino LJ, Miller M, Hedgecock AA, Thornley C, Matasi JJ, Davies HM. Local cerebral metabolic effects of the novel cocaine analog, WF-31: comparisons to fluoxetine. Synapse 1997; 27:26-35. [PMID: 9268062 DOI: 10.1002/(sici)1098-2396(199709)27:1<26::aid-syn3>3.0.co;2-f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The effects of the acute administration of the selective serotonin uptake inhibitor, fluoxetine, on rates of local cerebral glucose utilization in rats were compared to those of the novel cocaine analog, [2beta-propanoyl-3beta-(4-isopropylphenyl)-tropane, WF-31, which has greater affinity for serotonin than dopamine transporters, using the quantitative autoradiographic 2-[14C]deoxyglucose method. Locomotor activity was assessed simultaneously. Fluoxetine administration resulted in dose-dependent decreases in locomotor behavior, as well as widespread reductions in rates of metabolic activity in brain areas including raphe nuclei, dorsal and ventral striatum, amygdala, hippocampus, limbic cortex, and thalamus. These effects were largely concentrated in brain regions containing high densities of serotonin transporters as revealed by in vitro autoradiography. In contrast, the acute administration of WF-31 produced more discrete changes in metabolic activity that were localized within the raphe nuclei and in portions of the hippocampal formation. Blockade of WF-31's dopaminergic effects by pretreatment with the antagonist, alpha-flupenthixol, resulted in a pattern of metabolic changes that closely resembled that observed with fluoxetine. These data suggest that the alterations in functional activity produced by both fluoxetine and WF-31 are largely the result of actions on serotonergic systems.
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Affiliation(s)
- L J Porrino
- Center for the Neurobiological Investigation of Drug Abuse, Department of Physiology and Pharmacology, Bowman Gray School of Medicine, Winston-Salem, North Carolina 27157, USA.
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8
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Abstract
Manipulation of brainstem serotonin (5-HT) raphe neurons induces significant alterations in local cerebral metabolism and perfusion. The vascular consequences of intracerebrally released 5-HT point to a major vasoconstrictor role, resulting in cerebral blood flow (CBF) decreases in several brain regions such as the neocortex. However, vasodilatations, as well as changes in blood-brain barrier (BBB) permeability, which are blocked by 5-HT receptor antagonists also can be observed. A lack of relationship between the changes in flow and metabolism indicates uncoupling between the two variables and is suggestive of a direct neurogenic control by brain intrinsic 5-HT neurons on the microvascular bed. In line with these functional data are the close associations that exist between 5-HT neurons and the microarterioles, capillaries and perivascular astrocytes of various regions but more intimately and/or more frequently so in those where CBF is altered significantly following manipulation of 5-HT neurons. The ability of the microvascular bed to respond directly to intracerebrally released 5-HT is underscored by the expression of distinct 5-HT receptors in the various cellular compartments of the microvascular bed. Thus, it appears that while some 5-HT-mediated microvascular functions involve directly the blood vessel wall, others would be relayed through the perivascular astrocyte. The strategic localization of perivascular astrocytes and the different 5-HT receptors that they harbor strongly emphasize their putative pivotal role in transmitting information between 5-HT neurons and microvessels. It is concluded that the cerebral circulation has full capacity to adequately and locally adapt brain perfusion to changes in central 5-HT neurotransmission either directly or indirectly via the neuronal-astrocytic-vascular tripartite functional unit. Dysfunctions in these neurovascular interactions might result in perfusion deficits and might be involved in specific pathological conditions.
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Affiliation(s)
- Z Cohen
- Laboratory of Cerebrovascular Research, Montréal Neurological Institute, McGill University, Québec, Canada
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9
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Kapur S, Meyer J, Wilson AA, Houle S, Brown GM. Modulation of cortical neuronal activity by a serotonergic agent: a PET study in humans. Brain Res 1994; 646:292-4. [PMID: 8069675 DOI: 10.1016/0006-8993(94)90091-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
This study investigates the effect of a serotonergic agent, fenfluramine, on neuronal activity, as measured using [18F]fluorodeoxyglucose (FDG) uptake with positron emission tomography (PET) in humans. Eleven subjects each received oral fenfluramine and placebo, on two different occasions, followed by FDG PET scans. Our study shows that fenfluramine modulates ongoing neuronal activity in a regionally specific fashion with a relative increase in metabolism in the prefrontal cortex and a relative decrease in the occipital-temporal regions.
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Affiliation(s)
- S Kapur
- Clarke Institute of Psychiatry, University of Toronto, Ont., Canada
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10
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Freo U, Ricchieri GL, Holloway HW, Soncrant TT. Time- and dose-dependent effects of the serotonergic agent quipazine on regional cerebral metabolism in rats. Brain Res 1993; 600:249-56. [PMID: 8435750 DOI: 10.1016/0006-8993(93)91380-b] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The time course and the relation to dose of regional cerebral metabolic rates for glucose (rCMRglc) were measured in awake male adult Fischer-344 rats after administration of quipazine, a serotonin 5-HT2-3 receptor agonist. rCMRglc was determined, using the quantitative autoradiographic [14C]deoxyglucose technique, in 92 brain regions at 30, 60, 90 and 120 min after quipazine 20 mg/kg i.p. and at 60 min after quipazine 5 mg/kg i.p. Peak metabolic effects were observed 60 min after quipazine 20 mg/kg i.p. when rCMRglc was significantly elevated in 27 (29%) brain regions (mean rise 17%). Quipazine increased rCMRglc in brain regions with high densities of 5-HT3 receptors (area postrema, olfactory tubercle, amygdala), in dopaminergic nuclei (substantia nigra pars compacta and pars reticulata) and terminal fields of their projections (zona incerta, subthalamic nucleus, preoptic magnocellular area, nucleus of facial nerve). The topographic distribution and direction of rCMRglc changes induced by quipazine are different from those produced by the 5-HT2 agonist 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane and, consistent with the pharmacological and binding properties of quipazine, suggest a preferential activation of 5-HT3 receptors.
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Affiliation(s)
- U Freo
- Unit on Pharmacology and Pharmacokinetics, National Institutes on Aging, National Institutes of Health, Bethesda, MD 20892
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11
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Wahl M, Schilling L, Unterberg A, Baethmann A. Mediators of vascular and parenchymal mechanisms in secondary brain damage. ACTA NEUROCHIRURGICA. SUPPLEMENTUM 1993; 57:64-72. [PMID: 7678480 DOI: 10.1007/978-3-7091-9266-5_10] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Several putative mediators of vasogenic brain edema will be considered with respect to the following criteria: 1) their effect on blood-brain barrier (BBB) permeability, 2) their vasomotor actions which may increase driving forces for transmural bulk flow, 3) their influence on edema formation, 4) their actual tissue concentration in pathological states, and 5) the therapeutic results after specific treatment. Bradykinin (BK) can induce brain edema by increasing BBB permeability to small solutes and enhancing blood pressure in the microcirculation due to arterial dilatation and venous constriction. Its interstitial concentration is enhanced after experimental trauma. Since kallikrein inhibitors reduce brain swelling all criteria favour BK as a mediator of vasogenic edema. Arachidonic acid (AA) opens BBB also for large tracers but exerts only small vasomotor effects. The edema formation is associated with an increase of the AA concentration in the interstitial space. However, convincing therapeutic results on inhibition of AA are still lacking. In addition to the formation of vasogenic edema AA has been found to induce cytotoxic edema. From experiments dealing with the vasomotor effects Ellis et al. (Am J Physiol 255: H397-H400, 1988) concluded an interaction of BK and AA in brain injury. However, our own results do not favour this hypothesis since we found divergent vasomotor and permeability effects of BK and AA. Histamine (HA) opens BBB unspecifically and dilates cerebral vessels, mechanisms by which edema formation can be explained.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M Wahl
- Department Physiology, Ludwig-Maximilians University, Munich, Federal Republic of Germany
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12
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Watson NV, Hargreaves EL, Penava D, Eckel LA, Vanderwolf CH. Serotonin-dependent cerebral activation: effects of methiothepin and other serotonergic antagonists. Brain Res 1992; 597:16-23. [PMID: 1477730 DOI: 10.1016/0006-8993(92)91500-e] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In scopolamine-treated (5.0 mg/kg, s.c.) rats hippocampal rhythmical slow activity (RSA) and neocortical low voltage fast activity (LVFA) occur only in close correlation with head movements, spontaneous changes in posture, or locomotion (Type I behavior). Previous work indicates that such scopolamine-resistant RSA and LVFA are dependent on ascending serotonergic projections. A test of 9 serotonergic antagonists (methiothepin; ritanserin; ketanserin; pizotifen; mianserin; pirenperone; ICS-205-930; metoclopramide; methysergide) showed that methiothepin produces a partial reduction in RSA and LVFA in scopolamine-treated rats, while the other antagonists are completely inactive over a wide range of doses. It may be that serotonergic cerebral activation depends on both 5-HT1 and 5-HT2 receptors.
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Affiliation(s)
- N V Watson
- Psychology Department, University of British Columbia, Vancouver, Canada
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13
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Bonvento G, MacKenzie ET, Edvinsson L. Serotonergic innervation of the cerebral vasculature: relevance to migraine and ischaemia. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 1991; 16:257-63. [PMID: 1790433 DOI: 10.1016/0165-0173(91)90009-w] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Multiple and complex interactions exist between the cerebral circulation and a potent vasoactive (and neurotransmitter) agent, serotonin. The nature and bases of the real and potential relationships are often hotly contested, for example, the serotonergic innervation of brain conducting and resistance vessels. In this review, an attempt is made to reconcile the available literature and to indicate future and possibly fruitful research directions. It appears that, by its very nature, the pattern of the serotonergic innervation is singular to blood vessels of the brain and could provide a neuronal link (or coupling) between functional events within the central nervous system and its perfusion which subserves changes in brain function. Finally, there are sufficient data to suggest an involvement of 5-hydroxytryptamine in different cerebrovascular pathologies.
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Affiliation(s)
- G Bonvento
- Centre Cyceron, CNRS SDI 6129, CEA DSV-DPTE, Caen, France
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14
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Palombo E, Porrino LJ, Crane AM, Bankiewicz KS, Kopin IJ, Sokoloff L. Cerebral metabolic effects of monoamine oxidase inhibition in normal and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine acutely treated monkeys. J Neurochem 1991; 56:1639-46. [PMID: 2013759 DOI: 10.1111/j.1471-4159.1991.tb02062.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induces dopaminergic cell death in the substantia nigra pars compacta (SNpc) and clinical parkinsonism in humans and experimental animals. Pretreatment with monoamine oxidase inhibitors prevents this cell death and associated parkinsonism by blocking the oxidation of MPTP to a toxic intermediate. The 2-deoxyglucose method was used to study the acute effects of MPTP in the monkey brain and the effects of monoamine oxidase inhibition on local cerebral glucose utilization in both normal and MPTP-treated monkeys. MPTP administration alone caused a major increase in glucose utilization in the SNpc and smaller increases in some subnuclei within the ventral tegmental area in which eventual dopaminergic cell loss also occurs. Pretreatment with pargyline abolished these metabolic increases, a finding suggesting both that the oxidized product of MPTP generates the metabolic increases and that the increased glucose consumption may contribute to cell toxicity. On the other hand, in most cortical, thalamic, striatal, brainstem, and cerebellar areas MPTP alone caused reductions in glucose utilization, and pargyline failed to prevent these effects. Pargyline alone depressed metabolism in the locus coeruleus and a few other monoaminergic structures.
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Affiliation(s)
- E Palombo
- Laboratory of Cerebral Metabolism, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
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15
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Freo U, Soncrant TT, Holloway HW, Rapoport SI. Dose- and time-dependent effects of 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), a serotonergic 5-HT2 receptor agonist, on local cerebral glucose metabolism in awake rats. Brain Res 1991; 541:63-9. [PMID: 2029625 DOI: 10.1016/0006-8993(91)91074-b] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The time course and the relation to dose of regional cerebral metabolic rates for glucose (rCMRglc) were measured in awake male Fischer-344 rats after administration of 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), a selective serotonergic 5-HT2 agonist. rCMRglc was determined, using the quantitative autoradiographic [14C]2-deoxyglucose technique, in 75 brain regions at 5, 15, 30, 60 and 90 min after administration of DOI 10 mg/kg i.p., and at 15 min after DOI 2.5, 25 or 50 mg/kg i.p. In non-hippocampal regions, peak effects were observed at 15-30 min, when rCMRglc in 12% of the regions was significantly different from control. In hippocampal regions rCMRglc effects peaked at 30 min (average rCMRglc reduction 21%) and were sustained for at least 60 min. Higher doses of DOI reduced rCMRglc in most prosencephalic regions (25 mg/kg, 35% of all regions studied; 50 mg/kg, 32%), where 5-HT2 receptors are present in high density. These data suggest that selective 5-HT2 receptor stimulation leads to rCMRglc reduction in areas with high densities of 5-HT2 receptors.
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Affiliation(s)
- U Freo
- Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD 20892
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16
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Affiliation(s)
- D L Murphy
- Laboratory of Clinical Science, National Institute of Mental Health, NIH Clinical Center, Bethesda, MD 20892
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17
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Sharma HS, Olsson Y, Dey PK. Changes in blood-brain barrier and cerebral blood flow following elevation of circulating serotonin level in anesthetized rats. Brain Res 1990; 517:215-23. [PMID: 2375992 DOI: 10.1016/0006-8993(90)91029-g] [Citation(s) in RCA: 119] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Plasma serotonin (5-HT) was elevated by an intravenous infusion of this amine into urethane-anaesthetized rats and the concentration approximated that present in various neurological diseases and mental abnormalities. An infusion of 10 micrograms per kg body weight for 10 min significantly increased blood-brain barrier (BBB) permeability to Evans blue and 131I-sodium measured in whole brain. Regional BBB determinations with labelled 131I-sodium showed that the permeability to this compound was increased in the cerebral cortex, hippocampus, caudate nucleus, hypothalamus, colliculus and the cerebellum but not in the pons and the medulla oblongata. Regional blood flow was reduced in the same parts which showed BBB abnormality tested with 125I-labeled microspheres. Pretreatment with cyproheptadine, a 5-HT2 receptor antagonist, prevented the BBB increase and the regional blood flow was near normal values. Similar effects were obtained with indomethacin, a prostaglandin synthesis inhibitor. Vinblastine, known to influence vesicular transport, eliminated extravasation of the tracers but the regional blood flow remained depressed. A hypothesis is put forward that serotonin after binding to its receptor in the cerebral vessels stimulates prostaglandin which either directly or by means of cyclic adenosine monophosphate causes an increased vesicular transport across the endothelial cells and thus an extravasation of tracer substances in the brain. Obviously, this form of exudation can be influenced by pharmacological means.
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Affiliation(s)
- H S Sharma
- Laboratory of Neuropathology, Institute of Pathology, University Hospital, Uppsala, Sweden
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18
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Freo U, Soncrant TT, Ricchieri GL, Wozniak KM, Larson DM, Rapoport SI. Time courses of behavioral and regional cerebral metabolic responses to different doses of meta-chlorophenylpiperazine in awake rats. Brain Res 1990; 511:209-16. [PMID: 2334843 DOI: 10.1016/0006-8993(90)90163-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The time course and relation to dose of regional cerebral metabolic rates for glucose (rCMRglc) and of motor behavior were measured in awake male adult Fischer-344 rats after administration of meta-chlorophenylpiperazine (MCPP), a serotonin-1B receptor agonist. rCMRglc was determined, using the quantitative autoradiographic [14C]deoxyglucose technique, in 71 brain regions at 5, 15, 30 and 60 min after administration of MCPP 2.5 mg/kg i.p., and at 15 min after MCPP 25 and 40 mg/kg. The time course of performance on a rotating rod was measured periodically for 60 min after MCPP 2.5 mg/kg, a dose which impaired locomotion and reduced rCMRglc maximally at 15-30 min after its administration. At 15 min, rCMRglc declined significantly in 28 (40%) of the areas studied (mean decline 16%). Most regions affected were telencephalic or diencephalic, corresponding to the projection areas of serotonergic fibers arising from the raphe nuclei. After higher doses of MCPP, a behavioral serotonin syndrome was observed with both rCMRglc increases and decreases (25 mg/kg) or only rCMRglc increases (40 mg/kg). Whereas behavioral and metabolic activation induced by high doses of MCPP may result from stimulation at postsynaptic serotonin receptors, rCMRglc reductions and hypomotility produced by MCPP 2.5 mg/kg resemble the effects of serotonin receptor antagonists and suggest that, at this low dose, MCPP acts at modulatory serotonin autoreceptors to reduce endogenous serotonin release.
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Affiliation(s)
- U Freo
- Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Bethesda, MD 20892
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19
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Wahl M, Unterberg A, Baethmann A, Schilling L. Mediators of vasogenic brain edema. J Basic Clin Physiol Pharmacol 1990; 1:221-33. [PMID: 1982223 DOI: 10.1515/jbcpp.1990.1.1-4.221] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- M Wahl
- Department of Physiology, Ludwig-Maximilians University, Munich, FRG
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20
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McBean DE, Sharkey J, Ritchie IM, Kelly PA. Chronic effects of the selective serotoninergic neurotoxin, methylenedioxyamphetamine, upon cerebral function. Neuroscience 1990; 38:271-5. [PMID: 2255397 DOI: 10.1016/0306-4522(90)90391-g] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The amphetamine derivative methylenedioxyamphetamine selectively destroys serotoninergic terminals in the brain. We have studied the effects of this toxin upon resting cerebral function, as reflected in rates of glucose utilization. Rats were injected subcutaneously with either 1 ml/kg saline (n = 5) or 20 mg/kg methylenedioxyamphetamine (n = 5) twice daily for four days. Local cerebral glucose utilization was measured between six and nine weeks after treatment using [14C]2-deoxyglucose quantitative autoradiography. Samples of frontal cortex taken from these animals for in vitro [3H]paroxetine binding showed a 64% reduction in 5-hydroxytryptamine uptake sites. In the majority of the 31 functionally diverse brain areas analysed, no significant changes were measured, but significant (P less than 0.05) increases in glucose use were found in neocortical regions e.g. anterior cingulate cortex (+16%) and sensorimotor cortex (+21%). However, the most profound increases were found in globus pallidus (+30%) and hippocampus molecular layer (+34%). It would appear, therefore, that treatment with methylenedioxyamphetamine results in long-lasting alterations in cerebral functional activity.
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Affiliation(s)
- D E McBean
- Department of Clinical Neurosciences, University of Edinburgh, Western General Hospital, U.K
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21
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Wilkerson G, London ED. Effects of methylenedioxymethamphetamine on local cerebral glucose utilization in the rat. Neuropharmacology 1989; 28:1129-38. [PMID: 2572994 DOI: 10.1016/0028-3908(89)90128-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The effects of (+-)3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") (5, 10, 15 or 30 mg/kg, i.p.) on local cerebral utilization of glucose were studied by the quantitative autoradiographic 2-deoxy-D-[1-14C]glucose method in awake adult male Fischer-344 rats. Statistically significant effects on local utilization of glucose, 5 min after the administration of MDMA were observed in 20 of 60 areas of brain sampled. Marked stimulation was seen in components of the extrapyramidal motor system (substantia nigra, globus pallidus, entopenduncular nucleus, subthalamic nucleus, cerebellar vermis). The limbic system showed decrements in the medial cortex and hippocampal dentate gyrus (outer blade) and the lateral habenula, while there was stimulation in the mammillary body and the basolateral amygdaloid nucleus. Glucose utilization in MDMA-treated rats was reduced in the superior colliculus and medial terminal nucleus of the accessory optic system, but was unchanged in the visual cortex and components of the auditory system. Some of the effects of MDMA on cerebral utilization of glucose resembled those previously reported with l-cocaine, d-amphetamine, and phencyclidine, implicating some common mechanisms in the actions of these drugs.
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Affiliation(s)
- G Wilkerson
- Neuropharmacology Laboratory, National Institute on Drug Abuse, Baltimore, Maryland 21224
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22
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Wahl M, Unterberg A, Baethmann A, Schilling L. Mediators of blood-brain barrier dysfunction and formation of vasogenic brain edema. J Cereb Blood Flow Metab 1988; 8:621-34. [PMID: 2843554 DOI: 10.1038/jcbfm.1988.109] [Citation(s) in RCA: 251] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- M Wahl
- Department of Physiology, Ludwig-Maximilans University, Munich, F.R.G
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23
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Palombo E, Porrino LJ, Bankiewicz KS, Crane AM, Kopin IJ, Sokoloff L. Administration of MPTP acutely increases glucose utilization in the substantia nigra of primates. Brain Res 1988; 453:227-34. [PMID: 3261197 DOI: 10.1016/0006-8993(88)90162-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The quantitative 2-[14C]deoxyglucose autoradiographic method was used to map the regional distribution of the acute effects of administration of the neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), on local cerebral glucose utilization in rhesus monkeys. Metabolic activity was increased (+80%) in the substantia nigra pars compacta, which has been shown to be the main target site of MPTP toxicity. Metabolic activity was also increased in the nucleus paranigralis, nucleus parabrachialis pigmentosus, and ventral lamella of the inferior olive. In contrast, substantial decreases in glucose utilization were found diffusely distributed throughout many of the other structures examined, most prominently in portions of the cerebral cortex, thalamus, and cerebellum.
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Affiliation(s)
- E Palombo
- Laboratory of Cerebral Metabolism, National Institute of Mental Health, Bethesda, MD 20892
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24
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Kelly PA, Davis CJ, Goodwin GM. Differential patterns of local cerebral glucose utilization in response to 5-hydroxytryptamine agonists. Neuroscience 1988; 25:907-15. [PMID: 2970017 DOI: 10.1016/0306-4522(88)90044-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Local cerebral glucose utilization was measured in parallel groups of conscious rats following intravenous injection of either 1 mg/kg 8-hydroxy-2-(di-N-propylamino)tetralin (a 5-hydroxytryptamine 1A binding site agonist), 3 mg/kg 5-methoxy 3-(1,2,3,6-tetrahydro-4-pyridinyl)1H indole, succinate (a 5-hydroxytryptamine1B agonist), or saline alone, using the 2-deoxyglucose quantitative autoradiographic techniques (n = 5 in each of the three groups). Following both drugs, local rates of glucose use in the majority of the 72 brain areas analysed remained unaltered, but in some other regions either increases or decreases were observed. In keeping with the observed behavioural response to 8-hydroxy-2-(di-N-propylamino)tetralin there were marked increases in cerebellum (+56%) and motor cortex where a columnar arrangement of increased metabolism (+34%) contrasted with adjacent columns of decrease (-26%). Hippocampal areas showed moderate decreases in glucose use (-13 to -21%). All areas which increased following 8-hydroxy-2-(di-N-propylamino)tetralin also increased following 5-methoxy 3-(1,2,3,6-tetrahydro-4-pyridinyl)1H indole, succinate, but in the latter case all elements of the basal ganglia were also increased, including globus pallidus (+105%) and the striatum where the changes (+54%) were limited to a discrete dorsal region of the nucleus. In the hippocampus only dorsal dentate gyrus was decreased (-24%) whilst a moderate increase (+16%) was observed in dorsal subiculum. The complexity of these results contrasts with previous 2-deoxyglucose investigations where less specific 5-hydroxytryptamine receptor ligands were used, and suggests that certain aspects of brain function may be selectively targeted by systemic pharmacological manipulation of endogenous serotonergic systems.
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Affiliation(s)
- P A Kelly
- Department of Physiology, University College Cardiff, U.K
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25
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Wree A, Schleicher A, Zilles K, Beck T. Local cerebral glucose utilization in the Ammon's horn and dentate gyrus of the rat brain. HISTOCHEMISTRY 1988; 88:415-26. [PMID: 3366647 DOI: 10.1007/bf00570304] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The local cerebral glucose utilization (LCGU) was measured in different regions and layers of the Ammon's horn and dentate gyrus in the conscious rat. The LCGU was determined by quantitative [14C]2-deoxyglucose autoradiography using a computerized image processing system. In the hippocampus, the various regions and layers exhibited different glucose consumptions, the lowest values being found in the alveus and the highest ones in the lacunosum-molecular layers of the sectors of the Ammon's horn and the molecular layer of the dentate gyrus' external limb. Additionally, in many layers, the LCGU values of the left hemispheres were found to be higher compared with the right hemispheres. The analysis of LCGU changes in rostrocaudal direction revealed, that in sector 1 of Ammon's horn and in the dentate gyrus the glucose consumption decreased from rostral to caudal levels, whereas in sector 3 of Ammon's horn an increase was found.
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Affiliation(s)
- A Wree
- Anatomisches Institut, Universität zu Köln, Federal Republic of Germany
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26
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Cudennec A, Duverger D, Serrano A, Scatton B, MacKenzie ET. Influence of ascending serotonergic pathways on glucose use in the conscious rat brain. II. Effects of electrical stimulation of the rostral raphé nuclei. Brain Res 1988; 444:227-46. [PMID: 3359294 DOI: 10.1016/0006-8993(88)90933-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Although lesions of the rostral raphé nuclei have minimal effects on integrated functional activity, as studied by the 2-deoxyglucose technique, the repercussions of activating the ascending serotonergic pathways have yet to be reported in the literature. To examine this question, we studied the consequences of the electrical stimulation of the rostral (median or dorsal) raphé nuclei on local cerebral glucose use in the conscious rat. Glucose use was determined by quantitative autoradiography in 105 defined brain structures. Raphé stimulation increased glucose utilization in a number of well-defined structures and pathways, dorsal raphé stimulation being systematically more effective than median raphé stimulation. Of all the neocortical regions studied, only the somatosensory cortex displayed a columnar and laminar pattern of increased glucose use that was restricted to the somatotopic delineation of the rat's head and face. Increased glucose use was seen in almost all key elements of the extrapyramidal system with the notable exception of the caudate-putamen. The thalamic nuclei that were activated by rostral raphé stimulation included those that subserve the processing of somesthetic, accessory visual and limbic information. Raphé stimulation-induced decreases in local cerebral glucose use were never observed. Almost all of the induced changes could be prevented or obtunded by prior intraventricular administration of the serotonergic neurotoxin 5,7-dihydroxytryptamine, suggesting that the majority of the raphé-induced changes in integrated functional activity were mediated via the activation of serotonergic neurones. The magnitude and pattern of the increases in glucose use could not always be correlated with the regional density of serotonergic innervation nor with the distribution of 5-hydroxytryptamine receptor subtypes in the adult brain. However, the pattern of increased cortical glucose use closely matches the selective serotonergic innervation of the somatosensory cortex found in early postnatal development. Thus, it would appear that the 2-deoxyglucose technique reveals functional units in the cortex that are innervated at an early ontogenic stage. We postulate that the discrete and highly organized changes in integrated functional activity that follow raphé stimulation are due to serotonin acting in a phasic manner on restricted, possibly specialized, postsynaptic structures.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- A Cudennec
- Département de Biologie, Laboratoires d'Etudes et de Recherches Synthélabo, Bagneux, France
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27
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Wree A, Schleicher A. The determination of the local cerebral glucose utilization with the 2-deoxyglucose method. HISTOCHEMISTRY 1988; 90:109-21. [PMID: 3068213 DOI: 10.1007/bf00500975] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In the adult mammalian brain, the energy metabolism is almost entirely dependent on glucose. Furthermore, a close relationship between the energy metabolism and the functional activity could be shown. Thus, the functional activity of the brain or parts thereof can be quantified by measuring the cerebral metabolic rate for glucose. Studying in vivo the fate of a radioactive labeled analogue of glucose, the 2-deoxy-D-[1-14C]glucose, and using quantitative autoradiographic techniques, it is possible to estimate the cerebral glucose utilization of every discrete brain region. The advantage of the 2-deoxyglucose method is, that the local cerebral glucose utilization represents a "metabolic encephalography" (Sokoloff 1982).
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Affiliation(s)
- A Wree
- Anatomisches Institut der Universität Würzburg, Federal Republic of Germany
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28
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Wree A, Zilles K, Schleicher A, Horváth E, Traber J. Effect of the 5-HT1A receptor agonist ipsapirone on the local cerebral glucose utilization of the rat hippocampus. Brain Res 1987; 436:283-90. [PMID: 2893652 DOI: 10.1016/0006-8993(87)91672-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Local cerebral glucose utilization (LCGU) was measured in the hippocampus of the rat brain following i.p. injection of the anxiolytic drug and 5-HT1A receptor agonist ipsapirone (TVX Q 7821). Administration of ipsapirone (5 mg/kg) reduced glucose utilization in the various hippocampal areas to variable extent. The most subtle reduction took place in the dorsal subiculum, while the most pronounced decrease was found in sector CA4 of Ammon's horn. The degree of LCGU reduction can be related to the 5-HT1A receptor density in the respective areas.
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Affiliation(s)
- A Wree
- Institute of Anatomy, University of Cologne, F.R.G
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