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Gasnier M, Ellul P, Plaze M, Ahad PA. A New Look on an Old Issue: Comprehensive Review of Neurotransmitter Studies in Cerebrospinal Fluid of Patients with Schizophrenia and Antipsychotic Effect on Monoamine's Metabolism. CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE 2021; 19:395-410. [PMID: 34294610 PMCID: PMC8316661 DOI: 10.9758/cpn.2021.19.3.395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 11/30/2020] [Accepted: 12/28/2020] [Indexed: 11/18/2022]
Abstract
Neurotransmitters metabolism has a key role in the physiopathology of schizophrenia as demonstrated by studies measuring monoamine metabolites in patient’s cerebrospinal fluid (CSF) since the beginning of the antipsychotic use. This comprehensive review aims to understand the anomalies of CSF monoamines in schizophrenia and their correlation with clinical and paraclinical features. We also review the influence of antipsychotic treatment on CSF monoamines and discuss the connection with metabolic and inflammatory processes. Studies comparing CSF homovanillic acid (HVA) levels between patients and controls are miscellaneous, due to the heterogeneity of samples studies. However, low HVA is associated with more positive symptoms and a poorer outcome and negatively correlated with brain ventricle size. Based on humans and animals’ studies, antipsychotic treatments increase HVA during the first week of administration and decrease progressively over the time with a fall-off after withdrawal. 5‐hydroxyindolacetic acetic acid levels do not seem to be different in the patient’s CSF compared to controls. Considering metabolic co-factors of neurotrans-mitters synthesis, there is evidence supporting an increase of kynurenic acid in the CSF of patients with schizophrenia. Few studies explore folate metabolism in CSF. Literature also emphasizes the relationship between folate metabolism, inflammation and monoamine’s metabolism. Those results suggest that the CSF monoamines could be correlated with schizophrenia symptoms and treatment outcome. However, further studies, exploring the role of CSF monoamines as biomarkers of disease severity and response to treatment are needed. They should assess the antipsychotic prescription, inflammatory markers and folate metabolism as potential confounding factors.
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Affiliation(s)
- Matthieu Gasnier
- Department of Psychiatry, MOODS Team, Paris Saclay University, Bicetre Hospital, AP-HP, Paris, France
| | - Pierre Ellul
- Department of Child and Adolescent Psychiatry, Robert Debré Hospital, AP-HP, Paris, France
| | - Marion Plaze
- Department of Psychiatry, Service Hospitalo Universitaire, Sainte Anne Hospital, Paris, France
| | - Pierre Abdel Ahad
- Department of Psychiatry, Service Hospitalo Universitaire, Sainte Anne Hospital, Paris, France
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Shiga Y, Kanaya Y, Kono R, Takeshima S, Shimoe Y, Kuriyama M. [Dementia with Lewy bodies presenting marked tongue protrusion and bite due to lingual dystonia: A case report]. Rinsho Shinkeigaku 2016; 56:418-423. [PMID: 27212676 DOI: 10.5692/clinicalneurol.cn-000843] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report the patient of a 53-year-old woman who developed subacute-onset marked tonge protrusion and bite. She was diagnosed as dementia with Lewy bodies (DLB) from the clinical features including progressive cognitive decline, visual hallucinations, parkinsonism, and severe insomnia and depression, and the radiological finding of low dopamine transported uptake in basal ganglia by Dat SCAN and low blood circulation in occipital lobe of cerebrum. The patient received 600 mg doses of levodopa for over a year, followed by rotigotine and ropinirole with a rapid increase of dosage. It is believed that these treatments stimulated and sensitized dopamine D1 receptors, thereby inducing lingual dystonia. Furthermore, the patient demonstrated dyspnea and attacks of apnea caused by the closure of bilateral vocal cords due to laryngeal dyskinesia. After initiation of the neuroleptic, olanzapine, for a short duration, the high dose of levodopa overlapped with neuroleptic sensitivity, suggesting DOPA-induced dystonia and dyskinesia. This interaction can sometimes lead to lethal adverse events, and must be considered very important when treating patients with DLB.
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Affiliation(s)
- Yuji Shiga
- Department of Neurology, Brain Attack Center Ota Memorial Hospital
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Brunelin J, Fecteau S, Suaud-Chagny MF. Abnormal striatal dopamine transmission in schizophrenia. Curr Med Chem 2014; 20:397-404. [PMID: 23157632 PMCID: PMC3866953 DOI: 10.2174/0929867311320030011] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Revised: 09/05/2012] [Accepted: 09/26/2012] [Indexed: 11/23/2022]
Abstract
Despite numerous revisions and reformulations, dopamine (DA) hypothesis of schizophrenia remains a pivotal neurochemical hypothesis of this illness. The aim of this review is to expose and discuss findings from positron emission tomography (PET) or single-photon-emission computed tomography (SPECT) studies investigating DA function in the striatum of medicated, drug-naïve or drug-free patients with schizophrenia and in individuals at risk compared with healthy volunteers.
DA function was studied at several levels: i) at a presynaptic level where neuroimaging studies investigating DOPA uptake capacity clearly show an increase of DA synthesis in patients with schizophrenia; ii) at a synaptic level where neuroimaging studies investigating dopamine transporter availability (DAT) does not bring any evidence of dysfunction; iii) and finally, neuroimaging studies investigating DA receptor density show a mild increase of D2 receptor density in basic condition and, an hyperreactivity of DA system in dynamic condition.
These results are discussed regarding laterality, sub-regions of striatum and implications for the at-risk population. Striatal DA abnormalities are now clearly demonstrated in patients with schizophrenia and at risk population and could constitute an endophenotype of schizophrenia. Subtle sub-clinical striatal DA abnormalities in at risk population could be a biomarker of transition from a vulnerability state to the expression of frank psychosis.
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Affiliation(s)
- Jerome Brunelin
- Université de Lyon, Université Lyon 1, F-69003, Lyon, France.
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POSTER COMMUNICATIONS. Br J Pharmacol 2012. [DOI: 10.1111/j.1476-5381.1982.tb17355.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Deep brain stimulation of the subthalamic or entopeduncular nucleus attenuates vacuous chewing movements in a rodent model of tardive dyskinesia. Eur Neuropsychopharmacol 2011; 21:393-400. [PMID: 20624675 DOI: 10.1016/j.euroneuro.2010.06.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 06/15/2010] [Accepted: 06/23/2010] [Indexed: 11/21/2022]
Abstract
Deep brain stimulation (DBS) has recently emerged as a potential intervention for treatment-resistant tardive dyskinesia (TD). Despite promising case reports, no consensus exists as yet regarding optimal stimulation parameters or neuroanatomical target for DBS in TD. Here we report the use of DBS in an animal model of TD. We applied DBS (100 μA) acutely to the entopeduncular nucleus (EPN) or subthalamic nucleus (STN) in rats with well established vacuous chewing movements (VCMs) induced by 12 weeks of haloperidol (HAL) treatment. Stimulation of the STN or EPN resulted in significant reductions in VCM counts at frequencies of 30, 60 or 130 Hz. In the STN DBS groups, effects were significantly more pronounced at 130 Hz than at lower frequencies, whereas at the EPN the three frequencies were equipotent. Unilateral stimulation at 130 Hz was also effective when applied to either nucleus. These results suggest that stimulation of either the EPN or STN significantly alleviates oral dyskinesias induced by chronic HAL. The chronic HAL VCM model preparation may be useful to explore mechanisms underlying DBS effects in drug-induced dyskinesias.
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Batool F, Haleem MA, Haleem DJ. Acute administration of clozapine and risperidone altered dopamine metabolism more in rat caudate than in nucleus accumbens: a dose-response relationship. Sci Pharm 2009; 78:259-74. [PMID: 21179339 PMCID: PMC3002801 DOI: 10.3797/scipharm.0907-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2009] [Accepted: 11/26/2009] [Indexed: 11/22/2022] Open
Abstract
The present study compares the extrapyramidal and neurochemical effects of clozapine and risperidone in rat caudate (corpus striatum) and nucleus accumbens (ventral striatum) dose-dependently. Animals injected with clozapine (2.5, 5.0 and 10.0 mg/kg IP) or risperidone (1.0, 2.5 and 5.0 mg/kg IP) in acute were sacrificed 1 h later to collect brain samples. Extrapyramidal side effects (EPS) in terms of locomotor activity and catalepsy were monitored in each animal after the drug or vehicle administration. Maximum cataleptic potentials were found only at high doses of clozapine (10.0 mg/kg; 60%) and risperidone (5.0 mg/kg; 100%). Neurochemical estimations were carried out by HPLC-EC. Both drugs at all doses significantly (p<0.01) increased the concentration of homovanillic acid (HVA), a metabolite of DA, in the caudate nucleus and decreased in nucleus accumbens. Levels of Dihydroxyphenylacetic acid (DOPAC) significantly (p<0.01) increased in the caudate by clozapine administration and decreased in the nucleus accumbens by the administration of both drugs in a dose-dependent manner. 5-Hydroxyindoleacetic acid (5-HIAA), the predominant metabolite of serotonin significantly decreased in the caudate and nucleus accumbens in a similar fashion. Levels of tryptophan (TRP) were remained insignificant in caudate and nucleus accumbens by the injections of two drugs. In caudate, clozapine and risperidone administrations significantly (p<0.01) decreased HVA/DA ratio and increased DOPAC/DA ratio in nucleus accumbens at all doses. The findings suggest the evidence for DA/5-HT receptor interaction as an important link in the lower incidence of EPS. The possible role of serotonin1A receptors in the pathophysiology of schizophrenia is also discussed.
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Affiliation(s)
- Farhat Batool
- Neurochemistry and Biochemical Neuropharmacology Research Laboratory, Dept of Biochemistry, University of Karachi, Karachi-75270, Pakistan.
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Lee LY, Farooqui AA, Dawe GS, Burgunder JM, Ong WY. Role of phospholipase A(2) in prepulse inhibition of the auditory startle reflex in rats. Neurosci Lett 2009; 453:6-8. [PMID: 19429004 DOI: 10.1016/j.neulet.2009.01.069] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2008] [Revised: 12/05/2008] [Accepted: 01/28/2009] [Indexed: 10/21/2022]
Abstract
High levels of calcium-independent phospholipase A(2) (iPLA(2)) are present in the striatum and cerebral cortex [W.Y. Ong, J.F. Yeo, S.F. Ling, A.A. Farooqui, Distribution of calcium-independent phospholipase A(2) (iPLA(2)) in monkey brain, J. Neurocytol. 34 (2005) 447-458], and several clinical investigations have suggested a possible role of altered iPLA(2) activity in neurodegenerative and psychiatric disorders. The present study was carried out to elucidate a possible effect of PLA(2) on prepulse inhibition (PPI) of the acoustic startle reflex. Rats that received intraperitoneal injection of the non-specific PLA(2) inhibitor, quinacrine, showed significantly decreased PPI at 76, 80, and 84dB, compared to saline injected controls. In addition, rats that received intrastriatal injection of antisense oligonucleotide to iPLA(2) showed significant reduction in PPI at prepulse intensities of 76 and 84dB compared to scrambled sense injected controls. Together, these findings point to a role of PLA(2) in PPI of the auditory startle reflex and sensorimotor gating.
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Affiliation(s)
- Li-Yen Lee
- Department of Anatomy, National University of Singapore, Singapore 119260, Singapore
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Stone JM, Morrison PD, Pilowsky LS. Glutamate and dopamine dysregulation in schizophrenia--a synthesis and selective review. J Psychopharmacol 2007; 21:440-52. [PMID: 17259207 DOI: 10.1177/0269881106073126] [Citation(s) in RCA: 253] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The dopamine hypothesis of schizophrenia is the principal explanatory model of antipsychotic drug action. Recent discoveries extend our understanding of the neurochemistry of schizophrenia, with increasing evidence of dysfunction in glutamate and GABA as well as dopamine systems. In this review, we study the evidence for dopaminergic dysfunction in schizophrenia, drawing data from neurochemical imaging studies. We also review the NMDA receptor hypofunction hypothesis of schizophrenia as a supplementary explanatory model for the illness. We examine predictions made by the NMDA receptor hypofunction hypothesis and consider how they fit with current neurochemical findings in patients and animal models. We consider the case for glutamatergic excitotoxicity as a key process in the development and progression of schizophrenia, and suggest ways in which glutamate and dopamine dysregulation may interact in the condition.
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Affiliation(s)
- James M Stone
- King's College London Institute of Psychiatry, London, UK.
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Samaha AN, Seeman P, Stewart J, Rajabi H, Kapur S. "Breakthrough" dopamine supersensitivity during ongoing antipsychotic treatment leads to treatment failure over time. J Neurosci 2007; 27:2979-86. [PMID: 17360921 PMCID: PMC6672560 DOI: 10.1523/jneurosci.5416-06.2007] [Citation(s) in RCA: 201] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Antipsychotics often lose efficacy in patients despite chronic continuous treatment. Why this occurs is not known. It is known, however, that withdrawal from chronic antipsychotic treatment induces behavioral dopaminergic supersensitivity in animals. How this emerging supersensitivity might interact with ongoing treatment has never been assessed. Therefore, we asked whether dopamine supersensitivity could overcome the behavioral and neurochemical effects of antipsychotics while they are still in use. Using two models of antipsychotic-like effects in rats, we show that during ongoing treatment with clinically relevant doses, haloperidol and olanzapine progressively lose their efficacy in suppressing amphetamine-induced locomotion and conditioned avoidance responding. Treatment failure occurred despite high levels of dopamine D2 receptor occupancy by the antipsychotic and was at least temporarily reversible by an additional increase in antipsychotic dose. To explore potential mechanisms, we studied presynaptic and postsynaptic elements of the dopamine system and observed that antipsychotic failure was accompanied by opposing changes across the synapse: tolerance to the ability of haloperidol to increase basal dopamine and dopamine turnover on one side, and 20-40% increases in D2 receptor number and 100-160% increases in the proportion of D2 receptors in the high-affinity state for dopamine (D2(High)) on the other. Thus, the loss of antipsychotic efficacy is linked to an increase in D2 receptor number and sensitivity. These results are the first to demonstrate that "breakthrough" supersensitivity during ongoing antipsychotic treatment undermines treatment efficacy. These findings provide a model and a mechanism for antipsychotic treatment failure and suggest new directions for the development of more effective antipsychotics.
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Affiliation(s)
- Anne-Noël Samaha
- Schizophrenia Program, Centre for Addiction and Mental Health, Toronto, Ontario, Canada M5T 1R8
| | - Philip Seeman
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada M5T 1R8
- Department of Pharmacology, University of Toronto, Toronto, Ontario, Canada M5S 1A8, and
| | - Jane Stewart
- Centre for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, Quebec, Canada H4B 1R6
| | - Heshmat Rajabi
- Centre for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, Quebec, Canada H4B 1R6
| | - Shitij Kapur
- Schizophrenia Program, Centre for Addiction and Mental Health, Toronto, Ontario, Canada M5T 1R8
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada M5T 1R8
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Kikuchi M, Wada Y, Higashima M, Nagasawa T, Takeda T, Koshino Y. Individual analysis of EEG band power and clinical drug response in schizophrenia. Neuropsychobiology 2005; 51:183-90. [PMID: 15870508 DOI: 10.1159/000085593] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The main purpose of this study was to investigate the relationship between short-term clinical outcome and changes in electroencephalogram (EEG) power after drug treatment in patients with schizophrenia, and also to compare two different methods for quantitative EEG analysis. EEG power analysis was performed by both conventional fixed frequency band and adjusted frequency band based on individual alpha frequency (IAF) in 16 drug-naive patients before and after drug administration. In the theta bands determined by both conventional fixed band and IAF methods, the EEG power after treatment was larger than that before treatment. In addition, there was a correlation between EEG power and clinical drug response evaluated by changes in BPRS score. With regard to this correlation, IAF methods showed no apparent advantage over methods using conventional fixed frequency bands. Conventional quantitative EEG analysis can still serve as a useful tool for the assessment of short-term outcome of drug treatment.
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Affiliation(s)
- Mitsuru Kikuchi
- Department of Psychiatry and Neurobiology, Graduate School of Medical Science, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-8641, Japan.
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Rogoza RM, Fairfax DF, Henry P, N-Marandi S, Khan RF, Gupta SK, Mishra RK. Electron spin resonance spectroscopy reveals alpha-phenyl-N-tert-butylnitrone spin-traps free radicals in rat striatum and prevents haloperidol-induced vacuous chewing movements in the rat model of human tardive dyskinesia. Synapse 2005; 54:156-63. [PMID: 15452862 DOI: 10.1002/syn.20078] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The typical antipsychotic drug haloperidol causes vacuous chewing movements (VCM) in rats, which are representative of early-Parkinsonian symptoms or later-onset extrapyramidal side effects of tardive dyskinesia (TD) in humans. Haloperidol (HP) has been hypothesized to potentiate increases in oxidative stress or free radical-mediated levels of toxic metabolites in rat striatum while simultaneous upregulating dopamine (DA)-D2 receptors leading to presumed DA supersensitivity. Alpha(alpha)-Phenyl-N-tert-butylnitrone (PBN) is an antioxidant used to combat oxidative stress and measure increases in PBN spin-adduct activity. Thus, the aim of this study was to investigate whether VCMs are related to upregulation of DA-D2 receptors or to increased levels of free radicals produced during oxidative stress, and whether PBN had any protective effects. Rats received daily chronic (28 day) i.p. injections of saline, haloperidol (2 mg/kg), PBN (150 mg/kg), or haloperidol + PBN. The VCM model was used to measure extrapyramidal side effects of drug treatments. Electron spin resonance (ESR) spectroscopy was performed to compare concentrations of free radical species in rats receiving injections of HP + PBN. To examine the upregulation of DA-D2 receptors, binding assays were carried out to assess the increase in DA-D(2) receptor numbers with respect to VCMs following treatment of rats injected with HP, PBN, and HP + PBN. Results of these experiments show that HP-induced VCMs in rats results from increases in oxidative cellular events and may not be related to increases in striatal DA-D(2) receptors.
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Affiliation(s)
- Raina M Rogoza
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Ontario, Canada L8N 3Z5
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Apud JA, Egan MF, Wyatt RJ. Neuroleptic withdrawal in treatment-resistant patients with schizophrenia: tardive dyskinesia is not associated with supersensitive psychosis. Schizophr Res 2003; 63:151-60. [PMID: 12892869 DOI: 10.1016/s0920-9964(02)00338-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The objective of this retrospective study was to determine whether tardive dyskinesia (TD) represents a risk factor for supersensitive psychosis (SS) by assessing the effect of medication withdrawal on ratings of psychopathology for 30 days following discontinuation of antipsychotic medication in patients with and without TD. The subjects were 101 treatment-resistant patients with schizophrenia who had been admitted to the inpatient service of Neuroscience Research Hospital (NRH), National Institute of Mental Health, between 1982 and 1994 to undergo studies involving discontinuation of antipsychotic medication. Patients were rated independently on a daily basis on the 22-item Psychiatric Symptom Assessment Scale (PSAS), an extended version of the Brief Psychiatric Rating Scale (BPRS). The overall frequency of TD was 35.6%. Tardive dyskinesia patients were older (p < 0.0006) and had suffered from schizophrenia for a longer time (p < 0.003) than No-TD patients. Repeated measure ANOVA revealed a "time" effect for all subgroups studied. The interaction TD x time, however, was not statistically significant for any of the clusters. Within-group analysis revealed significant differences against baseline for measures of positive symptoms, negative symptoms and abnormal involuntary movements in the No-TD group 3 and 4 weeks after antipsychotic withdrawal. In the TD group, however, the changes were observed only at 4 weeks following antipsychotic discontinuation in just two of the positive symptoms cluster. Between-group analyses revealed that, at baseline, the Mannerisms cluster (abnormal involuntary movements) was significantly higher in the TD group (p < 0.05). No significant differences were observed between any of the remaining clusters at baseline or at different times following drug withdrawal. In conclusion, the relationship between SS and TD could not be confirmed in a cohort of patients with treatment-resistant schizophrenia. In the present study, patients with no TD seemed to deteriorate faster than patients with TD in terms of psychopathology and abnormal involuntary movements. It is possible that both group of patients may undergo supersensitive receptor changes, and that these changes may be more pronounced but potentially reversible in the group without TD.
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Affiliation(s)
- Jose A Apud
- Neuropsychiatry Branch, National Institute of Mental Health, NIH, Bethesda, MD 20892-1379, USA.
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Turrone P, Seeman MV, Silvestri S. Estrogen receptor activation and tardive dyskinesia. CANADIAN JOURNAL OF PSYCHIATRY. REVUE CANADIENNE DE PSYCHIATRIE 2000; 45:288-90. [PMID: 10779888 DOI: 10.1177/070674370004500310] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To undertake a selective review of the epidemiology, etiology, and treatment of tardive dyskinesia (TD), with emphasis on the potential influence of estrogen in its expression. METHOD Both Medline and Psycinfo databases were used to search for articles with the following key words: tardive dyskinesia, humans, animals, dopamine, estrogen, estrogen replacement therapy, antioxidants and oxidative stress. RESULTS The studies reviewed here suggest that estrogen modulates dopamine-mediated behaviours and that it protects against oxidative stress-induced cell damage caused by long-term exposure to antipsychotic medication. CONCLUSIONS Estrogen's multimodal role in the central nervous system may prove useful for the amelioration or prevention of TD. All the evidence suggests that a placebo-controlled, randomized trial with safer forms of estrogen should be conducted in postmenopausal women with TD.
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Affiliation(s)
- P Turrone
- Institute of Medical Science, University of Toronto, Ontario.
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Piggott MA, Marshall EF, Thomas N, Lloyd S, Court JA, Jaros E, Burn D, Johnson M, Perry RH, McKeith IG, Ballard C, Perry EK. Striatal dopaminergic markers in dementia with Lewy bodies, Alzheimer's and Parkinson's diseases: rostrocaudal distribution. Brain 1999; 122 ( Pt 8):1449-68. [PMID: 10430831 DOI: 10.1093/brain/122.8.1449] [Citation(s) in RCA: 239] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Dementia with Lewy bodies (DLB) is a neuropsychiatric disease associated with extrapyramidal features which differ from those of Parkinson's disease, including reduced effectiveness of L-dopa and severe sensitivity reactions to neuroleptic drugs. Distinguishing Alzheimer's disease from DLB is clinically relevant in terms of prognosis and appropriate treatment. Dopaminergic activities have been investigated at coronal levels along the rostrocaudal striatal axis from a post-mortem series of 25 DLB, 14 Parkinson's disease and 17 Alzheimer's disease patients and 20 elderly controls. [(3)H]Mazindol binding to the dopamine uptake site was significantly reduced in the caudal putamen in DLB compared with controls (57%), but not as extensively as in Parkinson's disease (75%), and was unchanged in Alzheimer's disease. Among three dopamine receptors measured (D1, D2 and D3), the most striking changes were apparent in relation to D2. In DLB, [(3)H]raclopride binding to D2 receptors was significantly reduced in the caudal putamen (17%) compared with controls, and was significantly lower than in Parkinson's disease at all levels. D2 binding was significantly elevated at all coronal levels in Parkinson's disease compared with controls, most extensively in the rostral putamen (71%). There was no change from the normal pattern of D2 binding in Alzheimer's disease. The only significant alteration in D1 binding ([(3)H]SCH23390) in the groups examined was an elevation (30%) in the caudal striatum in Parkinson's disease. There were no differences in D3 binding, measured using [(3)H]7-OH-DPAT, in DLB compared with controls. A slight, significant decrease in D3 binding in the caudal striatum of Parkinson's disease (13%) patients and an increase in Alzheimer's disease (20%) in the dorsal striatum at the level of the nucleus accumbens were found. The concentration and distribution of dopamine were disrupted in both DLB and Parkinson's disease, although in the caudate nucleus the loss of dopamine in DLB was uniform whereas in Parkinson's disease the loss was greater caudally. In the caudal putamen, dopamine was reduced by 72% in DLB and by 90% in Parkinson's disease. The homovanillic acid : dopamine ratio, a metabolic index, indicated compensatory increased turnover in Parkinson's disease, which was absent in DLB despite the loss of substantia nigra neurons (49%), dopamine and uptake sites. These differences between DLB, Parkinson's disease and Alzheimer's disease may explain some characteristics of the extrapyramidal features of DLB and its limited response to L-dopa and severe neuroleptic sensitivity. The distinct changes in the rostrocaudal pattern of expression of dopaminergic parameters are relevant to the interpretation of the in vivo imaging and diagnosis of DLB.
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Affiliation(s)
- M A Piggott
- MRC Neurochemical Pathology Unit, Department of Neuropathology, Old Age Psychiatry, Newcastle General Hospital, Newcastle-upon-Tyne, NE4 6BE, UK.
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Schröder J, Silvestri S, Bubeck B, Karr M, Demisch S, Scherrer S, Geider FJ, Sauer H. D2 dopamine receptor up-regulation, treatment response, neurological soft signs, and extrapyramidal side effects in schizophrenia: a follow-up study with 123I-iodobenzamide single photon emission computed tomography in the drug-naive state and after neuroleptic treatment. Biol Psychiatry 1998; 43:660-5. [PMID: 9582999 DOI: 10.1016/s0006-3223(97)00442-3] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Animal and postmortem studies indicate that neuroleptic therapy may induce D2 dopamine receptor up-regulation in the basal ganglia. METHODS To address this phenomenon in a clinical study, we investigated the D2 dopamine receptor binding in 15 DSM-III-R schizophrenics in the drug-naive state and 3 days after completion of a standardized neuroleptic therapy (benperidol 12-16 mg/day, for 25 days) using single photon emission computed tomography (SPECT). SPECT scans were obtained 2 hours after intravenous injection of 185 MBq 123I-iodobenzamide. For analysis, basal ganglia to frontal cortex (BG/FC) ratios were calculated and the patient sample was subgrouped into patients with a favorable versus a poor treatment response. RESULTS Neuroleptic treatment led to decreased BG/FC ratios in patients with a favorable response, but increased ratios in the poor responders (df = 1, F = 4.1, p = .06). Changes of BG/FC ratios were significantly correlated with extrapyramidal side effects but not with neurological soft signs. CONCLUSIONS Our findings suggest that neuroleptic therapy may induce D2 dopamine receptor up-regulation in a subgroup of patients characterized by poor treatment response and pronounced extrapyramidal side effects.
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Affiliation(s)
- J Schröder
- Department of Psychiatry, University of Heidelberg, Germany
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Bowden C, Theodorou AE, Cheetham SC, Lowther S, Katona CL, Crompton MR, Horton RW. Dopamine D1 and D2 receptor binding sites in brain samples from depressed suicides and controls. Brain Res 1997; 752:227-33. [PMID: 9106461 DOI: 10.1016/s0006-8993(96)01460-6] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Dopamine D1 and D2 receptors were measured (by saturation binding of [3H]SCH23390 and [3H]raclopride) in caudate, putamen and nucleus accumbens, obtained at post-mortem from suicide victims with a firm retrospective diagnosis of depression, and matched controls. There were no differences in the number or affinity of D1 or D2 receptors between suicides who had been free of antidepressants for at least three months prior to death, and controls. Increased numbers and decreased affinity of D2 receptors were however found in each brain region of antidepressant-treated suicides. We argue that these increases are related to concurrent treatment with neuroleptics rather than a direct effect of antidepressants. Increased numbers of D1 receptors in antidepressant-treated suicides were seen only in nucleus accumbens. This increase could not be clearly attributed to neuroleptics and may be related to antidepressant treatment.
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Affiliation(s)
- C Bowden
- Department of Pharmacology and Clinical Pharmacology, St. George's Hospital Medical School, London, UK
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19
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Mulcrone J, Kerwin RW. No difference in the expression of the D4 gene in post-mortem frontal cortex from controls and schizophrenics. Neurosci Lett 1996; 219:163-6. [PMID: 8971805 DOI: 10.1016/s0304-3940(96)13191-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The primary biochemical theory of schizophrenia has centered on the role of dopaminergic dysfunction in the illness. The D2 receptor has been primarily indicated however, some atypical neuroleptics may not act at D2. The D4 receptor has a high affinity for the atypical antipsychotic clozapine and is therefore a potential target for drug design. The role of D4 in the aetiology of schizophrenia has, however, been the subject of controversy. Using radioligand binding assays some researchers have detected an elevation of D4-like receptors in schizophrenic striatum whilst conversely other workers claim that D4 receptors are undetectable in this region. Analysis of receptor levels is difficult due to the lack of a ligand selective for D4. We have therefore examined D4 at the level of gene expression. D4 mRNA levels have been examined in post-mortem frontal cortex from nine controls and eight schizophrenics using a reverse transcription-polymerase chain reaction (RT-PCR) method. No significant difference in D4 mRNA levels was found between the two groups. This result does not support a major role for variability of D4 gene expression in the aetiology of schizophrenia.
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Affiliation(s)
- J Mulcrone
- Department of Psychological Medicine, Institute of Psychiatry, London, UK
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20
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Karolewicz B, Antkiewicz-Michaluk L, Michaluk J, Vetulani J. Different effects of chronic administration of haloperidol and pimozide on dopamine metabolism in the rat brain. Eur J Pharmacol 1996; 313:181-6. [PMID: 8911913 DOI: 10.1016/0014-2999(96)00451-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We investigated the differences between the action of haloperidol and pimozide on dopamine metabolism and on catalepsy in periods up to 6 weeks after cessation of chronic administration of the neuroleptics to male Wistar rats. Dopamine and its metabolites (dihydroxyphenylacetic and homovanillic acids) were measured, using high-performance liquid chromatography (HPLC), in the frontal cortex, nucleus accumbens, and striatum. Both neuroleptics produced similar effects after a single dose: catalepsy and an increase of dopamine metabolism in the brain structures. However, haloperidol and pimozide differed after chronic treatment. In haloperidol-treated rats hypersensitivity of the dopaminergic system developed at the end of 2 weeks' administration, as evidenced by depression of dopamine metabolism. The biochemical changes were accompanied by behavioral hyperactivity that lasted up to 3 weeks. Dopamine metabolism in rats treated with pimozide was normal from 24 h after the end of the treatment, while catalepsy was maintained at the high level for up to 8 days and was observable up to 3 weeks after the last dose. Our results suggest that in contrast to haloperidol, pimozide is not able to produce adaptive changes leading to supersensitivity of the dopaminergic system. This may be the consequence of its potent Ca2+ channel blocking action.
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Affiliation(s)
- B Karolewicz
- Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
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21
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Nyberg S, Farde L, Halldin C. Test-retest reliability of central [11C]raclopride binding at high D2 receptor occupancy. A PET study in haloperidol-treated patients. Psychiatry Res 1996; 67:163-71. [PMID: 8912956 DOI: 10.1016/0925-4927(96)02921-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Central D2 dopamine receptor occupancy may be a useful measure to establish clinical guidelines for optimal antipsychotic drug treatment. The use of positron emission tomography (PET) to explore quantitative relationships among D2 receptor occupancy and clinical effects depends on the reliability of such measurements. The calculation of D2 receptor occupancy using [11C]raclopride is routinely based on a ratio-equilibrium analysis, in which the ratio of radioactivity concentration in the striatum to that in the cerebellum is determined. To examine the reliability of such ratios, a test-retest analysis was performed in four schizophrenic patients treated with haloperidol decanoate. PET experiments with [11C]raclopride were repeated in each subject during the same day. The putamen to cerebellum ratio (P/C ratio) ranged from 1.44 to 1.07 among the four patients, corresponding to a D2 receptor occupancy of 62 to 71%. In each subject, the P/C ratios remained highly similar, with quotients 0.98, 1.01, 1.04 and 1.06 between the two experiments. The high test-retest reproducibility of the P/C ratios indicates that measurements of D2 receptor occupancy with the present methods are highly reliable, and support the further use of PET to optimize the drug treatment of schizophrenia.
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Affiliation(s)
- S Nyberg
- Karolinska Institute, Department of Clinical Neuroscience, Karolinska Hospital, Stockholm, Sweden.
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22
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Bench CJ, Lammertsma AA, Grasby PM, Dolan RJ, Warrington SJ, Boyce M, Gunn KP, Brannick LY, Frackowiak RS. The time course of binding to striatal dopamine D2 receptors by the neuroleptic ziprasidone (CP-88,059-01) determined by positron emission tomography. Psychopharmacology (Berl) 1996; 124:141-7. [PMID: 8935809 DOI: 10.1007/bf02245614] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Positron emission tomography (PET) and 11C-raclopride were used to assess the time course of binding to central dopamine D2 receptors by the novel neuroleptic ziprasidone. In a third party blind study, six healthy male control subjects received a predose of 40 mg ziprasidone and were scanned at an interval of between 4 and 36 h post-dose. One additional subject was assigned to placebo predose and was scanned at 4 h post-dose. Binding potential (BP) was compared with that seen in the subject predosed with placebo and with that seen in nine unmedicated normal volunteers. Subjects studied up to 12 h post-dose had BPs that were greater than 2 SD less than the mean BP, indicative of extensive D2 receptor binding by ziprasidone. With increasing time between dosing and PET scanning there was a curvilinear increase in BP, so that all studies performed at or after 18 h post-dose gave BPs in the normal range (mean +/- 2 SD). Elevated prolactin levels returned to within the normal range by 18 h post-dose. PET measures of binding potential correlated significantly with serum levels of ziprasidone at the time of scanning and less significantly with absolute prolactin levels at the same time.
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Affiliation(s)
- C J Bench
- MRC Cyclotron Unit, Hammersmith Hospital, London, UK
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23
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Wang GJ, Volkow ND, Logan J, Fowler JS, Schlyer D, MacGregor RR, Hitzemann RJ, Gjedde A, Wolf AP. Serotonin 5-HT2 receptor availability in chronic cocaine abusers. Life Sci 1995; 56:PL299-303. [PMID: 8614247 DOI: 10.1016/0024-3205(95)00090-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Serotonin 5-HT2 receptor availability was evaluated in chronic cocaine abusers (n = 19) using positron emission tomography and F-18 N-methylspiperone and was compared to control subjects (n =19). 5-HT2 Receptor availability was measured in frontal, occipital, cingulate and orbitofrontal cortices using the ratio of the distribution volume in the region of interest to that in the cerebellum which is a function of Bmax/Kd. 5-HT2 Receptor availability was significantly higher in cingulate and orbitofrontal cortices than in other frontal regions or occipital cortex. The values were not different in normal subjects and cocaine abusers. These results did not show any changes in 5-HT2 receptor availability in cocaine abusers as compared to the control subjects.
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Affiliation(s)
- G J Wang
- Medical Department, Brookhaven National Laboratory, Upton, New York 11973, USA
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24
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Affiliation(s)
- G P Reynolds
- Department of Biomedical Science, University of Sheffield, United Kingdom
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25
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Reynolds GP, Czudek C. New approaches to the drug treatment of schizophrenia. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 1995; 32:461-503. [PMID: 7748802 DOI: 10.1016/s1054-3589(08)61020-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- G P Reynolds
- Department of Biomedical Science, University of Sheffield, United Kingdom
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26
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Abstract
The present article discusses the distribution of free radical processes in the central nervous system (CNS). Specifically, we discuss the involvement of oxyradicals in the normal metabolism of catecholamine. We also review some proposals related to the possible importance of these compounds in the development of neuropsychiatric and movement disorders such as schizophrenia and neuroleptic-induced tardive dyskinesia (TD), respectively. Clinical studies have shown that antioxidant treatment can attenuate the movement abnormalities observed in TD. Further studies are necessary to evaluate the status of specific scavenging systems in these two disorders. The prophylactic use of antioxidants in patients who are treated with neuroleptics needs also to be considered.
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Affiliation(s)
- J L Cadet
- Molecular Neuropsychiatry Section, NIH/NIDA, Baltimore, MD 21224
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27
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Abstract
The dopamine hypothesis of schizophrenia has been central to the understanding of the mechanism of action of the antipsychotic drugs. Certainly the close correlation between drug dosage and affinity for D2 dopamine receptors indicates the importance of these receptors in the antipsychotic response, although D2 antagonism can also induce acute extrapyramidal side effects. The antipsychotic drugs also act at other neurotransmitter receptors, and these actions contribute to the unwanted side effects of treatment. The use of selective D2 antagonists can diminish such effects, although effects at other receptors are reported to be of value in minimizing extrapyramidal syndromes as well as in enhancing response either directly or by diminishing negative symptoms. The present understanding of these receptor mechanisms is reviewed.
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Affiliation(s)
- G P Reynolds
- Department of Biomedical Science, University of Sheffield, United Kingdom
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28
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Pilowsky LS, Costa DC, Ell PJ, Verhoeff NP, Murray RM, Kerwin RW. D2 dopamine receptor binding in the basal ganglia of antipsychotic-free schizophrenic patients. An 123I-IBZM single photon emission computerised tomography study. Br J Psychiatry 1994; 164:16-26. [PMID: 8137105 DOI: 10.1192/bjp.164.1.16] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We used SPECT to examine striatal D2 receptor binding in 20 antipsychotic-free DSM-III-R schizophrenic patients and 20 age- and sex-matched normal controls. Dynamic single-slice SPECT, at a slice chosen to include the basal ganglia, began immediately following intravenous injection of 185 MBq of 123I-IBZM. A semiquantitative approach was used to generate indices of specific D2 receptor binding in the basal ganglia. There was no overall elevation of D2 receptor binding between patients and controls. A male sex-specific left lateralised asymmetry of striatal D2 receptor binding was found in the patient group. Age-dependent decline of striatal D2 receptors was confirmed in controls, but not in patients. These results suggest that alterations in striatal D2 receptor distribution and density do occur in schizophrenia, and possibly reflect wider disruptions in prefrontal-striatal-limbic circuits.
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Affiliation(s)
- L S Pilowsky
- Institute of Psychiatry, De Crespigny Park, London
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29
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MESH Headings
- 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine/adverse effects
- Animals
- Antipsychotic Agents/adverse effects
- Disease Models, Animal
- Double-Blind Method
- Dyskinesia, Drug-Induced/drug therapy
- Dyskinesia, Drug-Induced/metabolism
- Free Radicals/metabolism
- Humans
- Oxidopamine/adverse effects
- Parkinson Disease, Secondary/chemically induced
- Parkinson Disease, Secondary/drug therapy
- Parkinson Disease, Secondary/metabolism
- Rats
- Rats, Sprague-Dawley
- Vitamin E/therapeutic use
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Affiliation(s)
- J L Cadet
- Unit on Cellular and Molecular Neurotoxicology, NIDA, ARC, Baltimore, MD 21224
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30
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Bench CJ, Lammertsma AA, Dolan RJ, Grasby PM, Warrington SJ, Gunn K, Cuddigan M, Turton DJ, Osman S, Frackowiak RS. Dose dependent occupancy of central dopamine D2 receptors by the novel neuroleptic CP-88,059-01: a study using positron emission tomography and 11C-raclopride. Psychopharmacology (Berl) 1993; 112:308-14. [PMID: 7871035 DOI: 10.1007/bf02244926] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Positron emission tomography (PET) and 11C-raclopride were used to measure the occupancy of central dopamine D2 receptors by a new neuroleptic, CP-88,059-1. In a double blind dose escalation study, seven healthy male subjects received a predose of between 2 mg and 60 mg CP-88,059-1, 5 h before PET scanning. One additional subject was assigned to placebo predose. Receptor occupancy was defined as the percentage reduction in binding potential compared with that seen in the subject predosed with placebo and with that seen in seven unmedicated normal volunteers previously studied. Binding of 11C-raclopride decreased in a dose dependent manner, and 85% dopamine D2 receptor occupancy was achieved with the highest dose of CP-88,059-1. The findings confirm that brain dopamine D2 receptors are blocked by CP-88,059-1 and suggest that an effective antipsychotic dose will be between 20 mg and 40 mg. The study high-lights the potential of positron emission tomography in the preclinical evaluation of new drugs.
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Affiliation(s)
- C J Bench
- MRC Cyclotron Unit, Hammersmith Hospital, London, UK
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31
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Sora I, Fujiwara Y, Tomita H, Ishizu H, Akiyama K, Otsuki S, Yamamura HI. Lack of effect of haloperidol or methamphetamine treatment on the mRNA levels of two dopamine D2 receptor isoforms in rat brain. THE JAPANESE JOURNAL OF PSYCHIATRY AND NEUROLOGY 1992; 46:967-73. [PMID: 1304623 DOI: 10.1111/j.1440-1819.1992.tb02868.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In order to investigate whether changes of the two mRNAs encoding the D2 receptor isoforms were induced by chronic haloperidol or methamphetamine treatment in rats, we measured the brain mRNA levels using in situ hybridization histochemistry (ISHH). We used two oligonucleotide probes, an "insert" probe to hybridize with the longer D2 receptor, D2(444), mRNA, and a "spanning" probe to hybridize with the shorter D2 receptor, D2(415), mRNA. Both D2 mRNAs were detected by ISHH in the caudate putamen, nucleus accumbens, substantia nigra, pars compacta and ventral tegmental area. The distributions and the amounts of the mRNAs for the two D2 isoforms did not change after chronic administration of haloperidol (1 mg/kg/day for 14 days, ip) or methamphetamine (4 mg/kg/day for 14 days, ip). These results suggest that the changes of D2 receptor density induced by chronic neuroleptic and psychostimulant treatment are not due primarily to receptor expression.
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Affiliation(s)
- I Sora
- Department of Pharmacology, College of Medicine, University of Arizona Health Science Center, Tucson
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32
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Reynolds GP, Brown JE, McCall JC, Mackay AV. Dopamine receptor abnormalities in the striatum and pallidum in tardive dyskinesia: a post mortem study. J Neural Transm (Vienna) 1992; 87:225-30. [PMID: 1533773 DOI: 10.1007/bf01245368] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Dopamine D1 and D2 receptors were determined in brain tissue taken post mortem from schizophrenic patients previously known to have had tardive dyskinesia and yet who had not received neuroleptic drug treatment for over one year prior to death. In comparison with age-matched control subjects, diminished D2 receptor density was observed in striatal regions, while these receptors appeared to be increased in the pallidum, an area of the brain particularly implicated in the production of dyskinesias. D 1 receptors showed similar tendencies to lower numbers in the striatum in tardive dyskinesia.
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Affiliation(s)
- G P Reynolds
- Department of Biomedical Science, University of Sheffield, United Kingdom
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33
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Jeste DV, Lohr JB, Manley M. Study of neuropathologic changes in the striatum following 4, 8 and 12 months of treatment with fluphenazine in rats. Psychopharmacology (Berl) 1992; 106:154-60. [PMID: 1549643 DOI: 10.1007/bf02801966] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Persistent tardive dyskinesia is a serious side effect of long-term treatment with neuroleptics. Although striatal pathologic changes are believed to underlie this potentially irreversible iatrogenic syndrome, the nature of the neuroleptic-induced neuropathology is unclear. In the present study, we treated rats with either vehicle or fluphenazine decanoate (5 mg/kg, IM) every 2 weeks for 4, 8 or 12 months. Four to nine weeks after the last injection, the animals were sacrificed and the density of cells in the central part of the striatum was measured with a computerized image-analysis system. The control and experimental animals did not differ in body weight with 4 and 8 months of treatment, but the rats treated with fluphenazine for 12 months had significantly lower body weights than comparable controls. Four months of neuroleptic use produced no significant neuropathologic changes. The animals treated with fluphenazine for 8 months had a significantly lower density of the large neurons. In the 12-month-treated group, there was no significant difference between the control and experimental animals, probably because of a 'floor effect': the density of the large neurons was significantly lower in the 12-month-treated compared to the 8-month-treated control rats.
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Affiliation(s)
- D V Jeste
- Department of Psychiatry, University of California, San Diego
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34
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Kerwin R. Merck, Sharp & Dohme Prize for Young Psychopharmacologists: A history of frontal and temporal lobe aspects of the neuropharmacology of schizophrenia. J Psychopharmacol 1992; 6:230-40. [PMID: 22291356 DOI: 10.1177/026988119200600217] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In the past two decades neurobiological research into schizophrenia has seen a shift of emphasis from the dopaminergic pharmacology of subcortical systems to areas of abnormality inferred from direct studies, i.e. frontal cortex and medial temporal lobe. Recent research has tried to integrate morphological abnormalities with neurochemical and pharmacological data. These integrated approaches have uncovered neurochemical systems other than dopamine which are of importance. This approach has led to greater understanding of neurochemical mechanisms associated with these abnormalities and may provide novel approaches for therapeutic intervention.
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Affiliation(s)
- R Kerwin
- Institute of Psychiatry, Consultant Psychiatrist, Maudsley Hospital, Denmark Hill, London SE5, UK
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35
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Jackson-Lewis V, Przedborski S, Kostic V, Suber F, Fahn S, Cadet JL. Partial attenuation of chronic fluphenazine-induced changes in regional monoamine metabolism by D-alpha-tocopherol in rat brain. Brain Res Bull 1991; 26:251-8. [PMID: 1707329 DOI: 10.1016/0361-9230(91)90235-c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Recent evidence has suggested a role for free radicals in tardive dyskinesia. We, therefore, investigated the effects of chronic administration of fluphenazine decanoate (FLU) and/or vitamin E (VIT E) on regional monoamine metabolism in rat brain. Chronic FLU caused significant increases in dopamine (DA) in nucleus accumbens and brainstem, significant decreases in dihydroxyphenylacetic acid (DOPAC) in frontal cortex, nucleus accumbens and hippocampus and significant decreases in homovanillic acid (HVA) in nucleus accumbens, caudate-putamen and brainstem. Coadministration of FLU and VIT E normalized HVA in caudate-putamen, nucleus accumbens and brainstem as well as DOPAC in nucleus accumbens and hippocampus. Chronic FLU caused significant increases in norepinephrine (NE) levels in all regions studied. VIT E attenuated FLU-induced increases in NE levels in nucleus accumbens and hippocampus. Significant increases in serotonin (5-HT) levels occurred in nucleus accumbens and hippocampus whereas significant decreases in 5-hydroxyindole-acetic acid (5-HIAA) occurred in all brain regions after chronic FLU. Coadministration of VIT E attenuated the changes observed in hippocampal 5-HIAA but potentiated the FLU-induced increases in 5-HT in this region. Our data suggest that VIT E can attenuate some of the FLU-induced changes in monoamine metabolism. Results are discussed in relation to possible involvement of free radicals in monoamine metabolism during chronic neuroleptic use.
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Affiliation(s)
- V Jackson-Lewis
- Department of Neurology, Columbia-Presbyterian Medical Center, New York, NY 10032
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36
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Masuda Y, Murai S, Saito H, Abe E, Fujiwara H, Kohori I, Itoh T. The enhancement of the hypomotility induced by small doses of haloperidol in the phase of dopaminergic supersensitivity in mice. Neuropharmacology 1991; 30:35-40. [PMID: 2046878 DOI: 10.1016/0028-3908(91)90039-e] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Dopaminergic supersensitivity in mice was induced by pretreatment with a single injection of haloperidol (4.8 mg/kg). After the pretreatment, further treatment with haloperidol (0.6 or 0.01 mg/kg) was made at varying intervals, and catalepsy, locomotor activity and homovanillic acid (HVA) were measured. The intensity of the supersensitivity was evaluated by enhanced apomorphine (1 mg/kg)-induced climbing behavior. Supersensitivity was displayed on the 2nd and the 4th day. The cataleptogenic effect of haloperidol (0.6 mg/kg) was significantly weakened on the 1st, 2nd and 4th days. The motor inhibitory effect of haloperidol (0.01 mg/kg) increased on the 1st, 2nd and 4th days. Homovanillic acid was measured in the striatum and the prefrontal cortex on the 2nd day. Haloperidol (0.6 mg/kg) increased the concentrations of HVA in both regions of the brain. The increase in the concentrations of HVA in the striatum was blunted after the pretreatment, but such tolerance did not develop in the prefrontal cortex. Haloperidol (0.01 mg/kg) did not influence the concentration of HVA in both regions. These results suggest that the behavioral effect of a small dose of haloperidol may be enhanced, rather than reduced, in the phase of supersensitivity.
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Affiliation(s)
- Y Masuda
- Department of Pharmacology, School of Dentistry, Iwate Medical University, Morioka, Japan
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37
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Goss JR, Kelly AB, Johnson SA, Morgan DG. Haloperidol treatment increases D2 dopamine receptor protein independently of RNA levels in mice. Life Sci 1991; 48:1015-22. [PMID: 1705651 DOI: 10.1016/0024-3205(91)90367-k] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Haloperidol, administered to mice in their drinking water, produced a 21% increase in striatal D2 dopamine receptor density after seven days of continuous exposure. The steady-state D2 receptor RNA prevalence was unaffected by this treatment, yet the RNA coding for preproenkephalin was elevated, as expected. These data indicate that the homologous up-regulation of dopamine receptor density by antipsychotic drugs proceeds by mechanisms other than changes in RNA abundance.
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Affiliation(s)
- J R Goss
- Andrus Gerontology Center, University of Southern California, Los Angeles 90089-0191
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38
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Grace AA. Phasic versus tonic dopamine release and the modulation of dopamine system responsivity: a hypothesis for the etiology of schizophrenia. Neuroscience 1991; 41:1-24. [PMID: 1676137 DOI: 10.1016/0306-4522(91)90196-u] [Citation(s) in RCA: 1211] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A novel mechanism for regulating dopamine activity in subcortical sites and its possible relevance to schizophrenia is proposed. This hypothesis is based on the regulation of dopamine release into subcortical regions occurring via two independent mechanisms: (1) transient or phasic dopamine release caused by dopamine neuron firing, and (2) sustained, "background" tonic dopamine release regulated by prefrontal cortical afferents. Behaviorally relevant stimuli are proposed to cause short-term activation of dopamine cell firing to trigger the phasic component of dopamine release. In contrast, tonic dopamine release is proposed to regulate the intensity of the phasic dopamine response through its effect on extracellular dopamine levels. In this way, tonic dopamine release would set the background level of dopamine receptor stimulation (both autoreceptor and postsynaptic) and, through homeostatic mechanisms, the responsivity of the system to dopamine in these sites. In schizophrenics, a prolonged decrease in prefrontal cortical activity is proposed to reduce tonic dopamine release. Over time, this would elicit homeostatic compensations that would increase overall dopamine responsivity and thereby cause subsequent phasic dopamine release to elicit abnormally large responses.
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Affiliation(s)
- A A Grace
- Department of Behavioral Neuroscience, University of Pittsburgh, PA 15260
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39
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Kazawa T, Mikuni M, Higuchi T, Arai I, Takahashi K, Yamauchi T. Characterization of sulpiride-displaceable 3H-YM-09151-2 binding sites in rat frontal cortex and the effects of subchronic treatment with haloperidol on cortical D-2 dopamine receptors. Life Sci 1990; 47:531-7. [PMID: 2402179 DOI: 10.1016/0024-3205(90)90613-v] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We investigated the pharmacological properties of the sulpiride-displaceable binding sites labeled by 3H-YM-09151-2 in rat frontal cortex, compared to those in striatum. The IC50 value of ketanserin was 486 nM, which was apparently different from its affinity for the 5HT-2 receptor. Various dopamine antagonists showed almost the same inhibitory effects for binding site in frontal cortex and striatum. Sulpiride-displaceable 3H-YM-09151-2 binding sites were considered to be D-2 dopamine receptors. After subchronic treatment with haloperidol, the D-2 receptor density of frontal cortex (0.55 fmol/mg tissue) increased to the same extent (about 25%) as striatum without significant change in apparent affinity.
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Affiliation(s)
- T Kazawa
- Department of Psychiatry, Saitama Medical School, Japan
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40
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Hernandez L, Baptista T, Hoebel BG. Neurochemical effects of chronic haloperidol and lithium assessed by brain microdialysis in rats. Prog Neuropsychopharmacol Biol Psychiatry 1990; 14 Suppl:S17-35. [PMID: 2097671 DOI: 10.1016/0278-5846(90)90084-t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
1. Psychotropic drugs ameliorate psychotic symptoms only after repeated administration. 2. To assess the neurochemical effects of chronic haloperidol and lithium administration, microdialysis was performed simultaneously in the prefrontal cortex, the nucleus accumbens, and the striatum after haloperidol, and separately in the lateral hypothalamus and the hippocampus after lithium. 3. Chronic administration of haloperidol decreased dopamine turnover in the prefrontal cortex and the striatum. It did not affect the nucleus accumbens detectably. 4. No tolerance to haloperidol developed in any of the three regions. 5. Lithium enhanced the response of the serotonergic system to amphetamine in the lateral hypothalamus but not in the hippocampus. 6. The antipsychotic effect of haloperidol might be related to dopamine turnover decrease in the prefrontal cortex. 7. The antidepressant effect of lithium might be related to enhancement of serotonin responsiveness in the hypothalamus.
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Affiliation(s)
- L Hernandez
- Laboratorio de Fisiologia del Comportamiento, Universidad de Los Andes, Merida, Venezuela
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41
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Cadet JL, Lohr JB. Possible involvement of free radicals in neuroleptic-induced movement disorders. Evidence from treatment of tardive dyskinesia with vitamin E. Ann N Y Acad Sci 1989; 570:176-85. [PMID: 2576510 DOI: 10.1111/j.1749-6632.1989.tb14918.x] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- J L Cadet
- Neurological Institute, Columbia University, New York, New York 10032
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42
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Abstract
The dopamine hypothesis still provides a valuable approach to the study of schizophrenia and its treatment by drugs. Although the neuroleptic drugs appear to act via an inhibition of dopamine receptors, measurements of dopamine metabolites in vivo, or of the transmitter and its receptors in post-mortem brain tissue, do not provide unequivocal evidence of a hyperactivity of dopaminergic neurotransmission in the disease. Nevertheless, increased dopamine function might be a consequence of a primary neuronal abnormality in another system. Recent imaging studies and neuropathological reports suggest that, in some patients, there may be a deficit and/or disturbance of neurons in certain temporal limbic regions, and this is supported by some neurochemical investigations, particularly of neuropeptide and amino-acid transmitter systems. A loss of such neurons could conceivably lead to a disinhibition of limbic dopamine neurons, providing the means whereby neuroleptic drug treatment might ameliorate the effects of a neuronal deficit in schizophrenia.
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Affiliation(s)
- G P Reynolds
- Department of Pathology, University of Nottingham Medical School, Queen's Medical Centre
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43
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Baker GB, Greenshaw AJ. Effects of long-term administration of antidepressants and neuroleptics on receptors in the central nervous system. Cell Mol Neurobiol 1989; 9:1-44. [PMID: 2565769 DOI: 10.1007/bf00711441] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
1. A review of the effects of long-term administration of antidepressants and neuroleptics on receptors in the central nervous system is presented. 2. The effects of antidepressants on adenylate cyclase activity and on receptor binding in brain tissue are discussed. Effects on a variety of receptor types are considered. 3. The utilization of electrophysiological, behavioral, and neurochemical studies to assess receptor function after chronic antidepressant administration is discussed, as is the use of peripheral receptor estimations in clinical studies. 4. Animal studies on the actions of chronic administration of neuroleptics on pre- and postsynaptic dopamine receptors are reviewed. Effects of these drugs on dopamine receptors in humans are considered from the following perspectives: postmortem and in vivo binding studies in schizophrenia, tardive dyskinesia, and central versus peripheral receptor estimation.
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Affiliation(s)
- G B Baker
- Department of Psychiatry, University of Alberta, Edmonton, Canada
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Affiliation(s)
- G P Reynolds
- Department of Pathology, University of Nottingham Medical School, Queen's Medical Centre
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46
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Kerr LM, Unis AS, Wamsley JK. Comparison of the density and distribution of brain D-1 and D-2 dopamine receptors in Buffalo vs. Fischer 344 rats. Pharmacol Biochem Behav 1988; 30:325-30. [PMID: 3051050 DOI: 10.1016/0091-3057(88)90462-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In vitro autoradiography was used to compare the D-1 and D-2 receptor densities in brains from Buffalo (BUFF) and Fischer 344 (F344) rats. The latter strain has been proposed as a model for human attention deficit disorder with hyperactivity (ADDH). The radioligands [3H]-SCH 23390 and [3H]-sulpiride were used to selectively identify dopamine D-1 and D-2 receptors, respectively. Certain forebrain structures from F344 rats have a higher density of D-2 receptors, but similar numbers of D-1 receptors compared to BUFF rats. Scatchard analysis of D-2 binding (in caudate-putamen) revealed a Bmax of 10.52 +/- 1.62 fmol/mg tissue and Kd of 12.72 +/- 0.93 nM in F344 rats and 3.00 +/- 0.57 and 3.87 +/- 0.58, respectively in BUFF rats (n = 3). These results support the hypothesis that high D-2 levels are correlated with certain behavioral traits, e.g., high levels of spontaneous activity. A similar increase in D-2 receptors may be responsible for some of the behavioral manifestations of ADDH in children.
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Affiliation(s)
- L M Kerr
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City 84132
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47
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Prosser ES, Csernansky JG, Hollister LE. Differences in the time course of haloperidol-induced up-regulation of rat striatal and mesolimbic dopamine receptors. Life Sci 1988; 43:715-20. [PMID: 2901023 DOI: 10.1016/0024-3205(88)90143-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Regional differences in the onset and persistence of increased dopamine D2 receptor density in rat brain were studied following daily injections of haloperidol for 3, 7, 14, or 28 days. Striatal [3H]-spiroperidol Bmax values were significantly increased following 3-28 days of haloperidol treatment, as compared to saline controls. Olfactory tubercle Bmax values were significantly increased only after 14 or 28 days of haloperidol treatment. Nucleus accumbens Bmax values were significantly increased only in the 14-day drug treatment group, suggesting that dopamine D2 receptor up-regulation in nucleus accumbens may reverse during ongoing neuroleptic treatment. These findings suggest that important differences in adaptive responses to chronic dopamine blockade may exist between dopaminergic synapses located in various rat brain regions.
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Affiliation(s)
- E S Prosser
- Veterans Administration Medical Center, Palo Alto, CA
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48
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Magnusson O, Mohringe B, Thorell G, Lake-Bakaar DM. Effects of the dopamine D2 selective receptor antagonist remoxipride on dopamine turnover in the rat brain after acute and repeated administration. PHARMACOLOGY & TOXICOLOGY 1987; 60:368-73. [PMID: 2886989 DOI: 10.1111/j.1600-0773.1987.tb01529.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The effects of the dopamine D2 selective receptor antagonist, remoxipride, on dopamine turnover in the rat brain were studied after acute and repeated administration and compared with the effects of haloperidol. Acute administration of remoxipride produced a dose-dependent increase of the concentrations of DOPAC and HVA in both striatum and olfactory tubercle + nucleus accumbens. The maximal effect of both acute remoxipride and haloperidol on dopamine turnover was attained approximately 2 hours after a single intraperitoneal administration, whereas a biphasic response was seen after oral remoxipride. Tolerance to the effects of repeated haloperidol (20 mumol/kg orally) treatment on dopamine turnover was observed as soon as after 3 days, whereas no such tolerance could be found during the first 15 days of repeated treatment with remoxipride (20 mumol/kg orally). A dose-related tolerance to the effects of remoxipride was, however, seen at higher dosages (40, 150 and 600 mumol/kg orally) and after a longer period (6 months) of treatment.
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Maidment NT, Marsden CA. Repeated atypical neuroleptic administration: effects on central dopamine metabolism monitored by in vivo voltammetry. Eur J Pharmacol 1987; 136:141-9. [PMID: 3595718 DOI: 10.1016/0014-2999(87)90705-9] [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: 01/06/2023]
Abstract
Changes in extracellular DOPAC levels were monitored simultaneously in the nucleus accumbens and striatum of halothane/N2O anaesthetised rats using in vivo differential pulse voltammetry with carbon fibre electrodes following repeated administration of the atypical neuroleptics thioridazine and clozapine. Thioridazine (20 mg/kg s.c.) increased the DOPAC peak in the nucleus accumbens and striatum of rats treated with saline for the previous 21 days by 66% +/- 5 S.E.M. and 91% +/- 16 respectively. No such increase was recorded in the nucleus accumbens of rats previously treated with thioridazine (20 mg/kg s.c.) for 21 days. Similarly the increase in the striatum produced by a challenge dose on day 22 was markedly attenuated compared to controls although analysis of absolute DOPAC peak heights revealed extracellular DOPAC to be elevated above basal levels in this region (but not the nucleus accumbens) indicating a possible selective action of this drug to induce absolute tolerance to its acute effects in the nucleus accumbens after repeated administration. Administration of increasing doses of apomorphine (0.05, 0.1, 0.25 mg/kg s.c.) 1 h after a challenge dose of thioridazine (20 mg/kg s.c.) on day 22 to rats treated with the neuroleptic for the previous 21 days produced a progressive decrease in extracellular DOPAC levels both in the nucleus accumbens and striatum. Repeated administration of clozapine (50 mg/kg s.c.) for 21 days failed to induce tolerance to the acute effects of this drug, extracellular DOPAC levels increasing by 60% +/- 8 and 90% +/- 18 in the nucleus accumbens and striatum respectively following challenge with the drug on day 22.(ABSTRACT TRUNCATED AT 250 WORDS)
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