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Holmes J, Witt CE, Keen D, Buchanan AM, Batey L, Hersey M, Hashemi P. Glutamate Electropolymerization on Carbon Increases Analytical Sensitivity to Dopamine and Serotonin: An Auspicious In Vivo Phenomenon in Mice? Anal Chem 2021; 93:10762-10771. [PMID: 34328714 DOI: 10.1021/acs.analchem.0c04316] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Carbon is the material of choice for electroanalysis of biological systems, being particularly applicable to neurotransmitter analysis as carbon fiber microelectrodes (CFMs). CFMs are most often applied to dopamine detection; however, the scope of CFM analysis has rapidly expanded over the last decade with our laboratory's focus being on improving serotonin detection at CFMs, which we achieved in the past via Nafion modification. We began this present work by seeking to optimize this modification to gain increased analytical sensitivity toward serotonin under the assumption that exposure of bare carbon to the in vivo environment rapidly deteriorates analytical performance. However, we were unable to experimentally verify this assumption and found that electrodes that had been exposed to the in vivo environment were more sensitive to evoked and ambient dopamine. We hypothesized that high in vivo concentrations of ambient extracellular glutamate could polymerize with a negative charge onto CFMs and facilitate response to dopamine. We verified this polymerization electrochemically and characterized the mechanisms of deposition with micro- and nano-imaging. Importantly, we identified that the application of 1.3 V as a positive upper waveform limit is a crucial factor for facilitating glutamate polymerization, thus improving analytical performance. Critically, information gained from these dopamine studies were extended to an in vivo environment where a 2-fold increase in sensitivity to evoked serotonin was achieved. Thus, we present here the novel finding that innate aspects of the in vivo environment are auspicious for detection of dopamine and serotonin at carbon fibers, offering a solution to our goal of an improved fast-scan cyclic voltammetry serotonin detection paradigm.
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Affiliation(s)
- Jordan Holmes
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, 29208 United States
| | - Colby E Witt
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, 29208 United States
| | - Deanna Keen
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, 29208 United States
| | - Anna Marie Buchanan
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, 29208 United States.,Department of Pharmacology, Physiology, & Neuroscience, University of South Carolina SOM, Columbia, South Carolina, 29209 United States
| | - Lauren Batey
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, 29208 United States.,Department of Bioengineering, Imperial College, London, SW7 2AZ UK
| | - Melinda Hersey
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, 29208 United States.,Department of Pharmacology, Physiology, & Neuroscience, University of South Carolina SOM, Columbia, South Carolina, 29209 United States
| | - Parastoo Hashemi
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, 29208 United States.,Department of Bioengineering, Imperial College, London, SW7 2AZ UK
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2
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Yu P, Wei H, Zhong P, Xue Y, Wu F, Liu Y, Fei J, Mao L. Single‐Carbon‐Fiber‐Powered Microsensor for In Vivo Neurochemical Sensing with High Neuronal Compatibility. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202010195] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Ping Yu
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Huan Wei
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Peipei Zhong
- Key Laboratory of Environmentally Friendly Chemistry and Applications of the Ministry of Education College of Chemistry Xiangtan University Xiangtan Hunan 411105 China
| | - Yifei Xue
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Fei Wu
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Yang Liu
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
| | - Junjie Fei
- Key Laboratory of Environmentally Friendly Chemistry and Applications of the Ministry of Education College of Chemistry Xiangtan University Xiangtan Hunan 411105 China
| | - Lanqun Mao
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
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3
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Yu P, Wei H, Zhong P, Xue Y, Wu F, Liu Y, Fei J, Mao L. Single‐Carbon‐Fiber‐Powered Microsensor for In Vivo Neurochemical Sensing with High Neuronal Compatibility. Angew Chem Int Ed Engl 2020; 59:22652-22658. [DOI: 10.1002/anie.202010195] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Indexed: 02/06/2023]
Affiliation(s)
- Ping Yu
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Huan Wei
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Peipei Zhong
- Key Laboratory of Environmentally Friendly Chemistry and Applications of the Ministry of Education College of Chemistry Xiangtan University Xiangtan Hunan 411105 China
| | - Yifei Xue
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Fei Wu
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Yang Liu
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
| | - Junjie Fei
- Key Laboratory of Environmentally Friendly Chemistry and Applications of the Ministry of Education College of Chemistry Xiangtan University Xiangtan Hunan 411105 China
| | - Lanqun Mao
- Beijing National Laboratory for Molecular Science Key Laboratory of Analytical Chemistry for Living Biosystems Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
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4
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Sung C, Jeon W, Nam KS, Kim Y, Butt H, Park S. Multimaterial and multifunctional neural interfaces: from surface-type and implantable electrodes to fiber-based devices. J Mater Chem B 2020; 8:6624-6666. [DOI: 10.1039/d0tb00872a] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Development of neural interfaces from surface electrodes to fibers with various type, functionality, and materials.
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Affiliation(s)
- Changhoon Sung
- Department of Bio and Brain Engineering
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 34141
- Republic of Korea
| | - Woojin Jeon
- Department of Bio and Brain Engineering
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 34141
- Republic of Korea
| | - Kum Seok Nam
- School of Electrical Engineering
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 34141
- Republic of Korea
| | - Yeji Kim
- Department of Bio and Brain Engineering
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 34141
- Republic of Korea
| | - Haider Butt
- Department of Mechanical Engineering
- Khalifa University
- Abu Dhabi 127788
- United Arab Emirates
| | - Seongjun Park
- Department of Bio and Brain Engineering
- Korea Advanced Institute of Science and Technology (KAIST)
- Daejeon 34141
- Republic of Korea
- KAIST Institute for Health Science and Technology (KIHST)
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5
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Ou Y, Buchanan AM, Witt CE, Hashemi P. Frontiers in Electrochemical Sensors for Neurotransmitter Detection: Towards Measuring Neurotransmitters as Chemical Diagnostics for Brain Disorders. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2019; 11:2738-2755. [PMID: 32724337 PMCID: PMC7386554 DOI: 10.1039/c9ay00055k] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
It is extremely challenging to chemically diagnose disorders of the brain. There is hence great interest in designing and optimizing tools for direct detection of chemical biomarkers implicated in neurological disorders to improve diagnosis and treatment. Tools that are capable of monitoring brain chemicals, neurotransmitters in particular, need to be biocompatible, perform with high spatiotemporal resolution, and ensure high selectivity and sensitivity. Recent advances in electrochemical methods are addressing these criteria; the resulting devices demonstrate great promise for in vivo neurotransmitter detection. None of these devices are currently used for diagnostic purposes, however these cutting-edge technologies are promising more sensitive, selective, faster, and less invasive measurements. Via this review we highlight significant technical advances and in vivo studies, performed in the last 5 years, that we believe will facilitate the development of diagnostic tools for brain disorders.
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Affiliation(s)
- Yangguang Ou
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia SC
| | - Anna Marie Buchanan
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia SC
| | - Colby E. Witt
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia SC
| | - Parastoo Hashemi
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia SC
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6
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Xiao T, Jiang Y, Ji W, Mao L. Controllable and Reproducible Sheath of Carbon Fibers with Single-Walled Carbon Nanotubes through Electrophoretic Deposition for In Vivo Electrochemical Measurements. Anal Chem 2018. [DOI: 10.1021/acs.analchem.8b00303] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Tongfang Xiao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanan Jiang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenliang Ji
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100190, China
| | - Lanqun Mao
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, Institute of Chemistry, The Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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7
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Ishida A, Imamura A, Ueda Y, Shimizu T, Marumoto R, Jung CG, Hida H. A novel biosensor with high signal-to-noise ratio for real-time measurement of dopamine levels in vivo. J Neurosci Res 2017; 96:817-827. [PMID: 29090830 PMCID: PMC5873456 DOI: 10.1002/jnr.24193] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 10/06/2017] [Accepted: 10/09/2017] [Indexed: 01/12/2023]
Abstract
Fast‐scan cyclic voltammetry (FSCV) is an established method for measuring dopamine (DA) levels in the brain in real time. However, it is difficult to discriminate DA from other monoamines such as serotonin (5‐hydroxytryptamine, 5‐HT) and norepinephrine (NE). We report a novel DA‐specific biosensor consisting of a carbon‐fiber electrode coated with an ion‐exchange membrane, a layer containing monoamine oxidase B, and a cellulose membrane. We performed FSCV using the probe to monitor the amount of DA in vitro and in vivo. First, we measured currents in vitro in phosphate‐buffered saline as we added one micromole each of DA, 5‐HT, and NE. The results confirmed that the biosensor selectively detected DA. Next, we implanted the probe in the striatum of male rats to investigate whether it could selectively detect changes in the DA content in vivo. The probe detected both the tonic change induced by methamphetamine administration and the phasic change induced by electrical stimulation of the medial forebrain bundle. In contrast, the electrode in the 6‐hydroxydopamine–lesioned striatum did not respond to systemic selective serotonin or serotonin/norepinephrine reuptake inhibitors, confirming its selectivity. Furthermore, the probe in the striatum could still detect changes in the DA level 1 week after electrode implantation. The results suggest that the novel biosensor can measure real‐time changes in DA levels in vivo with a relatively high signal‐to‐noise ratio.
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Affiliation(s)
- Akimasa Ishida
- Department of Neurophysiology and Brain Sciences, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Atsushi Imamura
- Department of Neurophysiology and Brain Sciences, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.,Intermedical Co., Ltd, Nagoya, Japan
| | - Yoshitomo Ueda
- Department of Neurophysiology and Brain Sciences, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Takeshi Shimizu
- Department of Neurophysiology and Brain Sciences, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Ryosuke Marumoto
- Department of Neurophysiology and Brain Sciences, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Cha-Gyun Jung
- Department of Neurophysiology and Brain Sciences, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Hideki Hida
- Department of Neurophysiology and Brain Sciences, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
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8
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Rodeberg NT, Sandberg SG, Johnson JA, Phillips PEM, Wightman RM. Hitchhiker's Guide to Voltammetry: Acute and Chronic Electrodes for in Vivo Fast-Scan Cyclic Voltammetry. ACS Chem Neurosci 2017; 8:221-234. [PMID: 28127962 PMCID: PMC5783156 DOI: 10.1021/acschemneuro.6b00393] [Citation(s) in RCA: 122] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Fast-scan cyclic voltammetry (FSCV) has been used for over 20 years to study rapid neurotransmission in awake and behaving animals. These experiments were first carried out with carbon-fiber microelectrodes (CFMs) encased in borosilicate glass, which can be inserted into the brain through micromanipulators and guide cannulas. More recently, chronically implantable CFMs constructed with small diameter fused-silica have been introduced. These electrodes can be affixed in the brain with minimal tissue response, which permits longitudinal measurements of neurotransmission in single recording locations during behavior. Both electrode designs have been used to make novel discoveries in the fields of neurobiology, behavioral neuroscience, and psychopharmacology. The purpose of this Review is to address important considerations for the use of FSCV to study neurotransmitters in awake and behaving animals, with a focus on measurements of striatal dopamine. Common issues concerning experimental design, data collection, and calibration are addressed. When necessary, differences between the two methodologies (acute vs chronic recordings) are discussed. The topics raised in this Review are particularly important as the field moves beyond dopamine toward new neurochemicals and brain regions.
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Affiliation(s)
- Nathan T. Rodeberg
- Department of Chemistry and ‡Neuroscience
Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
- Department of Psychiatry
and Behavioral Sciences and ∥Department of Pharmacology, University of Washington, Seattle, Washington 98195-6560, United States
| | - Stefan G. Sandberg
- Department of Chemistry and ‡Neuroscience
Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
- Department of Psychiatry
and Behavioral Sciences and ∥Department of Pharmacology, University of Washington, Seattle, Washington 98195-6560, United States
| | - Justin A. Johnson
- Department of Chemistry and ‡Neuroscience
Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
- Department of Psychiatry
and Behavioral Sciences and ∥Department of Pharmacology, University of Washington, Seattle, Washington 98195-6560, United States
| | - Paul E. M. Phillips
- Department of Chemistry and ‡Neuroscience
Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
- Department of Psychiatry
and Behavioral Sciences and ∥Department of Pharmacology, University of Washington, Seattle, Washington 98195-6560, United States
| | - R. Mark Wightman
- Department of Chemistry and ‡Neuroscience
Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
- Department of Psychiatry
and Behavioral Sciences and ∥Department of Pharmacology, University of Washington, Seattle, Washington 98195-6560, United States
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9
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Kim BJ, Kim YR, Seo M, Kim EJ, Jeon J, Chung TD. Electrochemical Impedance Spectroscopy at Well-Controlled dc Bias for Nanoporous Platinum Microelectrodes in Rat Embryo Brain. ChemElectroChem 2016. [DOI: 10.1002/celc.201600404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Beom Jin Kim
- Department of Chemistry; Seoul National University; Seoul 00826 Republic of Korea
| | - Yang-Rae Kim
- Department of Chemistry; Kwangwoon University; Seoul 01897 Republic of Korea
| | - Minjee Seo
- Department of Chemistry; Seoul National University; Seoul 00826 Republic of Korea
| | - Eun Joong Kim
- Department of Chemistry; Seoul National University; Seoul 00826 Republic of Korea
| | - Joohee Jeon
- Department of Chemistry; Seoul National University; Seoul 00826 Republic of Korea
| | - Taek Dong Chung
- Department of Chemistry; Seoul National University; Seoul 00826 Republic of Korea
- Advanced Institutes of Convergence Technology; Suwon-Si Gyeonggi-do 16229 Republic of Korea
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10
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Zhong P, Yu P, Wang K, Hao J, Fei J, Mao L. Ferricyanide-backfilled cylindrical carbon fiber microelectrodes for in vivo analysis with high stability and low polarized potential. Analyst 2015; 140:7154-9. [DOI: 10.1039/c5an01650a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A ferricyanide-backfilled cylindrical carbon fiber microelectrode of high stability and low polarized potential was fabricated and used for in vivo analysis.
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Affiliation(s)
- Peipei Zhong
- Key Laboratory of Environmental Friendly Chemistry and Applications of Ministry of Education
- College of Chemistry
- Xiangtan University
- Xiangtan
- China
| | - Ping Yu
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- the Chinese Academy of Sciences
- Beijing 100190
| | - Kai Wang
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- the Chinese Academy of Sciences
- Beijing 100190
| | - Jie Hao
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- the Chinese Academy of Sciences
- Beijing 100190
| | - Junjie Fei
- Key Laboratory of Environmental Friendly Chemistry and Applications of Ministry of Education
- College of Chemistry
- Xiangtan University
- Xiangtan
- China
| | - Lanqun Mao
- Beijing National Laboratory for Molecular Sciences
- Key Laboratory of Analytical Chemistry for Living Biosystems
- Institute of Chemistry
- the Chinese Academy of Sciences
- Beijing 100190
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11
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Nguyen MD, Venton BJ. Fast-scan Cyclic Voltammetry for the Characterization of Rapid Adenosine Release. Comput Struct Biotechnol J 2014; 13:47-54. [PMID: 26900429 PMCID: PMC4720017 DOI: 10.1016/j.csbj.2014.12.006] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 12/19/2014] [Accepted: 12/23/2014] [Indexed: 12/20/2022] Open
Abstract
Adenosine is a signaling molecule and downstream product of ATP that acts as a neuromodulator. Adenosine regulates physiological processes, such as neurotransmission and blood flow, on a time scale of minutes to hours. Recent developments in electrochemical techniques, including fast-scan cyclic voltammetry (FSCV), have allowed direct detection of adenosine with sub-second temporal resolution. FSCV studies have revealed a novel mode of rapid signaling that lasts only a few seconds. This rapid release of adenosine can be evoked by electrical or mechanical stimulations or it can be observed spontaneously without stimulation. Adenosine signaling on this time scale is activity dependent; however, the mode of release is not fully understood. Rapid adenosine release modulates oxygen levels and evoked dopamine release, indicating that adenosine may have a rapid modulatory role. In this review, we outline how FSCV can be used to detect adenosine release, compare FSCV with other techniques used to measure adenosine, and present an overview of adenosine signaling that has been characterized using FSCV. These studies point to a rapid mode of adenosine modulation, whose mechanism and function will continue to be characterized in the future.
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Affiliation(s)
- Michael D Nguyen
- Department of Chemistry, University of Virginia, McCormick Road, PO BOX 400319, Charlottesville, VA 22904, United States
| | - B Jill Venton
- Department of Chemistry, University of Virginia, McCormick Road, PO BOX 400319, Charlottesville, VA 22904, United States
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12
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Shnitko TA, Robinson DL. Anatomical and pharmacological characterization of catecholamine transients in the medial prefrontal cortex evoked by ventral tegmental area stimulation. Synapse 2014; 68:131-43. [PMID: 24285555 PMCID: PMC4060446 DOI: 10.1002/syn.21723] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 08/30/2013] [Accepted: 10/11/2013] [Indexed: 02/03/2023]
Abstract
Voltammetric measurements of catecholamines in the medial prefrontal cortex (mPFC) are infrequent because of lack of chemical selectivity between dopamine and norepinephrine and their overlapping anatomical inputs. Here, we examined the contribution of norepinephrine to the catecholamine release in the mPFC evoked by electrical stimulation of the ventral tegmental area (VTA). Initially, electrical stimulation was delivered in the midbrain at incremental depths of -5 to -9.4 mm from bregma while catecholamine release was monitored in the mPFC. Although catecholamine release was observed at dorsal stimulation sites that may correspond to the dorsal noradrenergic bundle (DNB, containing noradrenergic axonal projections to the mPFC), maximal release was evoked by stimulation of the VTA (the source of dopaminergic input to the mPFC). Next, VTA-evoked catecholamine release was monitored in the mPFC before and after knife incision of the DNB, and no significant changes in the evoked catecholamine signals were found. These data indicated that DNB fibers did not contribute to the VTA-evoked catecholamine release observed in the mPFC. Finally, while the D2-receptor antagonist raclopride significantly altered VTA-evoked catecholamine release, the α₂-adrenergic receptor antagonist idazoxan did not. Specifically, raclopride reduced catecholamine release in the mPFC, opposite to that observed in the striatum, indicating differential autoreceptor regulation of mesocortical and mesostriatal neurons. Together, these findings suggest that the catecholamine release in the mPFC arising from VTA stimulation was predominately dopaminergic rather than noradrenergic.
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Affiliation(s)
- Tatiana A. Shnitko
- Bowles Center for Alcohol Studies, University of North Carolina, Chapel Hill, NC, USA
| | - Donita L. Robinson
- Bowles Center for Alcohol Studies, University of North Carolina, Chapel Hill, NC, USA
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC, USA
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13
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West RH, Lu H, Shaw K, Chiel HJ, Kelley TJ, Burgess JD. Double Potential Pulse Chronocoulometry for Detection of Plasma Membrane Cholesterol Efflux at Disk Platinum Microelectrodes. JOURNAL OF THE ELECTROCHEMICAL SOCIETY 2014; 161:B111-B116. [PMID: 27330196 PMCID: PMC4909259 DOI: 10.1149/2.005406jes] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A double potential pulse scheme is reported for observation of cholesterol efflux from the plasma membrane of a single neuron cell. Capillary Pt disk microelectrodes having a thin glass insulator allow the 10 μm diameter electrode and cell to be viewed under optical magnification. The electrode, covalently functionalized with cholesterol oxidase, is positioned in contact with the cell surface resulting in enzyme catalyzed cholesterol oxidation and efflux of cholesterol from the plasma membrane at the electrode contact site. Enzymatically generated hydrogen peroxide accumulates at the electrode/cell interface during a 5 s hold-time and is oxidized during application of a potential pulse. A second, replicate potential pulse is applied 0.5 s after the first potential pulse to gauge background charge prior to significant accumulation of hydrogen peroxide. The difference in charge passed between the first and second potential pulse provides a measure of hydrogen peroxide generated by the enzyme and is an indication of the cholesterol efflux. Control experiments for bare Pt microelectrodes in contact with the cell plasma membrane show difference charge signals in the range of about 7-10 pC. Enzyme-modified electrodes in contact with the plasma membrane show signals in the range of 16-26 pC.
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Affiliation(s)
- Richard H. West
- Department of Chemistry, Case Western Reserve University and Rainbow Babies and Children’s Hospital, Cleveland, Ohio 44106
| | - Hui Lu
- Department of Biology, Case Western Reserve University and Rainbow Babies and Children’s Hospital, Cleveland, Ohio 44106
| | - Kendrick Shaw
- Department of Biology, Case Western Reserve University and Rainbow Babies and Children’s Hospital, Cleveland, Ohio 44106
| | - Hillel J. Chiel
- Department of Biology, Case Western Reserve University and Rainbow Babies and Children’s Hospital, Cleveland, Ohio 44106
| | - Thomas J. Kelley
- Department of Pediatrics and Pharmacology, Case Western Reserve University and Rainbow Babies and Children’s Hospital, Cleveland, Ohio 44106
| | - James D. Burgess
- Department of Chemistry, Case Western Reserve University and Rainbow Babies and Children’s Hospital, Cleveland, Ohio 44106
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14
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Arrigan D, Herzog G, Scanlon M, Strutwolf J. Bioanalytical Applications of Electrochemistry at Liquid-Liquid Microinterfaces. ELECTROANALYTICAL CHEMISTRY: A SERIES OF ADVANCES 2013. [DOI: 10.1201/b15576-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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15
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Gholivand MB, Amiri M. Highly sensitive and selective determination methyldopa in the presence of ascorbic acid using OPPy/TY/Au modified electrode. J Electroanal Chem (Lausanne) 2013. [DOI: 10.1016/j.jelechem.2013.01.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Mellander L, Cans AS, Ewing AG. Electrochemical probes for detection and analysis of exocytosis and vesicles. Chemphyschem 2010; 11:2756-63. [PMID: 20737529 DOI: 10.1002/cphc.201000258] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Unraveling the mechanistic details of neurotransmitter exocytosis is arguably among the most important molecular problems in neuroscience today. Investigations at single cells, particularly with electrochemical methods, have given unique chemical and biological insight into this process at the fundamental level. The rapid response time (submillisecond) of microelectrodes makes them well suited for monitoring the dynamic process of exocytosis. We review here recent developments in electrochemical techniques to spatially and simultaneously detect exocytosis across a single cell and to measure the transmitter content of single vesicles removed from cells. The former method is used to demonstrate dynamic heterogeneity in release across a cell, and in the latter work comparison is made between vesicle content and release to conclude that only a fraction of the transmitter is released during full exocytosis.
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Affiliation(s)
- Lisa Mellander
- Department of Chemistry, University of Gothenburg, 41296 Göteborg, Sweden
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Zheng M, Zhou Y, Chen Y, Tang Y, Lu T. Electrochemical behavior of dopamine in the presence of phosphonate and the determination of dopamine at phosphonate modified zirconia films electrode with highly antifouling capability. Electrochim Acta 2010. [DOI: 10.1016/j.electacta.2010.03.037] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Directed evolution of a magnetic resonance imaging contrast agent for noninvasive imaging of dopamine. Nat Biotechnol 2010; 28:264-70. [PMID: 20190737 DOI: 10.1038/nbt.1609] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2009] [Accepted: 01/27/2010] [Indexed: 11/08/2022]
Abstract
The development of molecular probes that allow in vivo imaging of neural signaling processes with high temporal and spatial resolution remains challenging. Here we applied directed evolution techniques to create magnetic resonance imaging (MRI) contrast agents sensitive to the neurotransmitter dopamine. The sensors were derived from the heme domain of the bacterial cytochrome P450-BM3 (BM3h). Ligand binding to a site near BM3h's paramagnetic heme iron led to a drop in MRI signal enhancement and a shift in optical absorbance. Using an absorbance-based screen, we evolved the specificity of BM3h away from its natural ligand and toward dopamine, producing sensors with dissociation constants for dopamine of 3.3-8.9 microM. These molecules were used to image depolarization-triggered neurotransmitter release from PC12 cells and in the brains of live animals. Our results demonstrate the feasibility of molecular-level functional MRI using neural activity-dependent sensors, and our protein engineering approach can be generalized to create probes for other targets.
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Adams KL, Puchades M, Ewing AG. In Vitro Electrochemistry of Biological Systems. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2008; 1:329. [PMID: 20151038 PMCID: PMC2819529 DOI: 10.1146/annurev.anchem.1.031207.113038] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
This article reviews recent work involving electrochemical methods for in vitro analysis of biomolecules, with an emphasis on detection and manipulation at and of single cells and cultures of cells. The techniques discussed include constant potential amperometry, chronoamperometry, cellular electroporation, scanning electrochemical microscopy, and microfluidic platforms integrated with electrochemical detection. The principles of these methods are briefly described, followed in most cases with a short description of an analytical or biological application and its significance. The use of electrochemical methods to examine specific mechanistic issues in exocytosis is highlighted, as a great deal of recent work has been devoted to this application.
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Affiliation(s)
- Kelly L. Adams
- Pennsylvania State University, Department of Chemistry, University Park, Pennsylvania 16802
- Göteborg University, Department of Chemistry, SE-412 96 Göteborg, Sweden
| | - Maja Puchades
- Göteborg University, Department of Chemistry, SE-412 96 Göteborg, Sweden
| | - Andrew G. Ewing
- Pennsylvania State University, Department of Chemistry, University Park, Pennsylvania 16802
- Göteborg University, Department of Chemistry, SE-412 96 Göteborg, Sweden
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Chen SM, Chen JY, Thangamuthu R. Electrochemical Preparation of Poly(Malachite Green) Film Modified Nafion-Coated Glassy Carbon Electrode and Its Electrocatalytic Behavior Towards NADH, Dopamine and Ascorbic Acid. ELECTROANAL 2007. [DOI: 10.1002/elan.200703861] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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21
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Chen SM, Liu JW, Thangamuthu R. Preparation, Characterization and Electrocatalytic Studies on Copper Complex Dye Film Modified Electrodes. ELECTROANAL 2007. [DOI: 10.1002/elan.200703875] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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22
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Justice JB, Wages SA, Michael AC, Blakely RD, Neill DB. Interpretations of Voltammetry in the Striatum Based on Chromatography of Striatal Dialysate. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/01483918308064897] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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23
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Chen SM, Liu JW, Thangamuthu R. Electropreparation of Poly(benzophenone-4) Film Modified Electrode and Its Electrocatalytic Behavior Towards Dopamine, Ascorbic Acid and Nitrite. ELECTROANAL 2006. [DOI: 10.1002/elan.200603672] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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24
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Cortright JJ, Rebec GV. Ascorbate modulation of sensorimotor processing in striatum of freely moving rats. Brain Res 2006; 1092:108-16. [PMID: 16753136 DOI: 10.1016/j.brainres.2006.03.079] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Revised: 03/22/2006] [Accepted: 03/23/2006] [Indexed: 10/24/2022]
Abstract
The striatum, which receives projections from the entire cortical mantle, is highly responsive to sensorimotor activity. Because either systemic or intra-striatal injections of ascorbate (AA) influence behavior known to involve striatal circuits, it is possible that the level of striatal AA, which is known to fluctuate with behavioral activation, directly alters striatal neuronal processing. To test this hypothesis, we recorded the activity of 94 presumed medium spiny striatal neurons in behaving rats treated with AA or vehicle and examined firing rate during periods of quiescence and sensorimotor stimulation (e.g., stroking of the whiskers, mid-back, and rump). Slow-scan voltammetry was used in separate rats to determine the extent to which AA treatment elevated striatal AA. Vehicle-treated rats had relatively slow basal firing rates at rest that routinely increased during sensorimotor stimulation. Comparable results were obtained in rats treated with 100 mg/kg AA, which failed to alter AA levels in striatum. Dose-dependent increases in striatal AA, however, occurred after injection of 500 and 1000 mg/kg AA, and at these doses, there was a significant decrease in the number of sensorimotor-related excitations. In fact, treatment with 1000 mg/kg AA reversed a significant proportion of excitations to inhibitions. Our results substantiate the role of the striatum in sensorimotor processing and emphasize extracellular AA as a modulator of striatal neuronal function.
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Affiliation(s)
- James J Cortright
- Program in Neuroscience, Department of Psychological and Brain Sciences, Psychology Building, 1101 E. Tenth Street, Indiana University, Bloomington, IN 47405-7007, USA
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25
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Zhang M, Liu K, Gong K, Su L, Chen Y, Mao L. Continuous On-Line Monitoring of Extracellular Ascorbate Depletion in the Rat Striatum Induced by Global Ischemia with Carbon Nanotube-Modified Glassy Carbon Electrode Integrated into a Thin-Layer Radial Flow Cell. Anal Chem 2005; 77:6234-42. [PMID: 16194084 DOI: 10.1021/ac051188d] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
This study describes a novel analytical system integrating in vivo microdialysis sampling with a radial thin-layer flow cell with a single-walled carbon nanotube (SWNT)-modified glassy carbon electrode as working electrode for continuous and on-line monitoring of ascorbate depletion in the rat striatum induced by global ischemia. The SWNTs, especially those after vacuum heat treatment at 500 degrees C, are found to be able to enhance the electron-transfer kinetics of ascorbate oxidation at a low potential (ca. -50 mV) and possess a strong ability against electrode fouling. These properties essentially make it possible to determine ascorbate with a good stability and high selectivity against catecholamines and their metabolites and other electroactive species of physiological levels. While being integrated with in vivo microdialysis to assemble an on-line analytical system, the electrode is proved useful for continuous and sensitive monitoring of the basal dialysate level of ascorbate and its depletion in the rat striatum induced by global ischemia. The basal dialysate level of ascorbate is determined to be 5.0 +/- 0.5 microM (n = 5) and a 50 +/- 10% (n = 3) depletion is recorded for the basal ascorbate after 4 h of global ischemia.
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Affiliation(s)
- Meining Zhang
- Center for Molecular Science, Institute of Chemistry, the Chinese Academy of Sciences, Beijing 100080, China
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26
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Teagarden MA, Rebec GV. Effects of long-term haloperidol treatment on glutamate-evoked ascorbate release in rat striatum. Eur J Pharmacol 2001; 418:213-6. [PMID: 11343692 DOI: 10.1016/s0014-2999(01)00942-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Repeated haloperidol injections increase extracellular striatal ascorbate. Because ascorbate release depends on glutamate uptake, we assessed this mechanism in the haloperidol effect. Linear staircase voltammetry was combined with intrastriatal infusions of L- or D-glutamate or saline in behaving rats after 7 or 21 days of haloperidol (0.5 mg/kg, s.c.). Control animals, receiving either vehicle or no treatment, responded to L-, but not D-glutamate or saline infusion with a 50% increase in ascorbate. In contrast, glutamate-evoked ascorbate release disappeared after 7 but reappeared after 21 days of haloperidol. Thus, increased striatal ascorbate release following chronic haloperidol cannot be explained by an enhanced response to glutamate.
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Affiliation(s)
- M A Teagarden
- Program in Neural Science, Department of Psychology, Indiana University, Psychology Building, Bloomington, IN 47405-7007, USA
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27
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Abstract
Ascorbate (vitamin C) is found in high concentrations in the striatum in which it may play a role in behavioral activation. To test this hypothesis, freely behaving rats received bilateral intrastriatal infusions of ascorbate oxidase (AAO) to inactivate extracellular ascorbate. Slow-scan voltammetry was used simultaneously to assess changes in ascorbate and 3,4-dihydroxyphenylacetic acid (DOPAC), a major dopamine metabolite, near the infusion site. Intrastriatal AAO, but not saline vehicle, caused a rapid decline in both ascorbate and behavioral activation. Within 20 min, an ascorbate loss of 50-70% led to a near-total inhibition of all recorded behavior, including open-field locomotion, approach of novel objects, and social interactions with other rats. DOPAC levels remained stable, arguing against an AAO-induced disruption of dopamine transmission. Consistent with this interpretation, subsequent injection of 1.0 mg/kg d-amphetamine, an indirect dopamine agonist, quickly restored behavioral activation, which also was accompanied by a marked rise in extracellular ascorbate. Bilateral AAO infusions into dorsal hippocampus, which also has a high level of extracellular ascorbate, failed to alter behavioral activation, indicating that a loss of brain ascorbate per se does not suppress behavior. Collectively, these results implicate ascorbate in the behavioral operations of the striatum and suggest that the extracellular level of this vitamin plays a critical role in behavioral activation.
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Logman MJ, Budygin EA, Gainetdinov RR, Wightman RM. Quantitation of in vivo measurements with carbon fiber microelectrodes. J Neurosci Methods 2000; 95:95-102. [PMID: 10752479 DOI: 10.1016/s0165-0270(99)00155-7] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Fast-scan cyclic voltammetry (FSCV) at carbon fiber disk microelectrodes and quantitative microdialysis were used to measure striatal concentration changes of N-acetyl-p-aminophenol (APAP, acetaminophen) following an intraperitoneal injection of 75 mg/kg APAP in rats. The goal of this work was to determine which in vitro calibration procedure, precalibration or postcalibration, gave the most accurate results when using carbon fiber microelectrodes in vivo. Voltammetric detection of APAP in vivo was complicated with normal electrodes by interference from pH changes. An electrode treatment was used to minimize electrode sensitivity to pH and this allowed successful APAP detection. In vitro calibrations of the treated carbon fiber disk microelectrodes before and after the in vivo experiment were used to calculate APAP concentration changes measured in vivo and compared to microdialysis results. The maximal striatal APAP concentration determined by microdialysis, adjusted for in vitro recovery, was 23.1 microM. The electrochemical results were approximately two times greater (postcalibration) or smaller (precalibration) than the microdialysis result.
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Affiliation(s)
- M J Logman
- Department of Chemistry, University of North Carolina at Chapel Hill, 27599-3290, USA
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29
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Stamford JA, Isaac D, Hicks CA, Ward MA, Osborne DJ, O'Neill MJ. Ascorbic acid is neuroprotective against global ischaemia in striatum but not hippocampus: histological and voltammetric data. Brain Res 1999; 835:229-40. [PMID: 10415378 DOI: 10.1016/s0006-8993(99)01587-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Following reports that ascorbic acid (AA) blocks NMDA receptors, we examined its possible neuroprotective properties in vivo (gerbil bilateral carotid artery occlusion model: BCAO) and in vitro (ischaemia-induced dopamine (DA) release in brain slices). Five minutes of BCAO caused substantial cell loss of 90-95% and 40-50% in gerbil CA1 hippocampus and striatum, respectively, measured in haematoxylin and eosin-stained sections, 5 days post-insult. AA (500 mg kg(-1) day(-1) i.p. for 312 days, first dose 1 h before occlusion) significantly (P<0.05) reduced striatal cell loss (from 40 to 13%) while only reducing CA1 cell loss from 95 to 88%. A lower dose (250 mg kg(-1) day(-1) i.p. for 312 days) was ineffective in either region. AA (750 mg kg(-1) day(-1) i.p. for 312 days) caused significant striatal protection (cell loss reduced from 49 to 20%) if treatment was initiated 1 h before occlusion. Initiation of treatment immediately post occlusion did not cause significant protection. Neither treatment regime protected CA1 hippocampus. In separate experiments we examined the effect of AA on DA release, monitored by voltammetry, in an in vitro model of striatal ischaemia. Four DA release variables were measured: T(on)--time from initiation of ischaemia to the onset of DA release, T(pk)--the time from onset of DA release to maximum, deltaDA/deltat--the mean rate of DA release and [DA](max)-- the maximum extracellular DA concentration. Control values in drug-naive slices were: T(on)=193+/-8 s, T(pk) = 24 +/- 4 s, [DA](max) = 69 +/- 6 microM and deltaDA/deltat = 4.2 +/- 0.7 microM s(-1) (means+/-S.E.M., n=15). 212 h pretreatment with AA (0.4 to 10 mM) did not affect T(on) or [DA](max) but increased T(pk) and decreased deltaDA/deltat (P<0.05) with an EC50 of 1.66 mM. NMDA (100 microM) shortened T(on). N-ethylmaleimide (20 microM) had no effect on the response to AA but potentiated the action of NMDA on T(on). AA (2 or 10 mM) had no effect on the response to NMDA. We conclude that AA is neuroprotective against global ischaemia in the striatum and that some of this action may be due to attenuation of ischaemia-induced DA release. This action is mediated neither by blockade of the NMDA receptor nor modulation of its redox status.
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Affiliation(s)
- J A Stamford
- Neurotransmission Laboratory, Academic Department of Anaesthesia and Intensive Care, St. Bartholomew's and the Royal London School of Medicine and Dentistry, Alexandra Wing, Royal London Hospital, Whitechapel, London, E1 1BB, UK.
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31
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Chen BT, Rice ME. Calibration Factors for Cationic and Anionic Neurochemicals at Carbon-Fiber Microelectrodes are Oppositely Affected by the Presence of Ca2+and Mg2+. ELECTROANAL 1999. [DOI: 10.1002/(sici)1521-4109(199905)11:5<344::aid-elan344>3.0.co;2-k] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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32
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Kind H, Bittner AM, Cavalleri O, Kern K, Greber T. Electroless Deposition of Metal Nanoislands on Aminothiolate-Functionalized Au(111) Electrodes. J Phys Chem B 1998. [DOI: 10.1021/jp981684o] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hannes Kind
- Institut de Physique Expérimentale, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Alexander M. Bittner
- Institut de Physique Expérimentale, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Ornella Cavalleri
- Institut de Physique Expérimentale, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Klaus Kern
- Institut de Physique Expérimentale, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Thomas Greber
- Physik-Institut, Universität Zürich, CH-8057 Zürich, Switzerland
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Rebec GV, Grabner CP, Johnson M, Pierce RC, Bardo MT. Transient increases in catecholaminergic activity in medial prefrontal cortex and nucleus accumbens shell during novelty. Neuroscience 1997; 76:707-14. [PMID: 9135044 DOI: 10.1016/s0306-4522(96)00382-x] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Voltammetric recordings with electrochemically modified carbon-fiber electrodes were obtained from specific regions of the forebrain in rats given free-choice access to a novel environment. Entry into novelty increased the catechol signal in the medial prefrontal cortex and shell of the nucleus accumbens by more than 100%, but had no consistent effect in either the neostriatum or accumbal core. In both the medial prefrontal cortex and accumbal shell, moreover, the novelty-induced increase in catecholaminergic activity was detectable only during the initial entry into the novel compartment and did not reappear when animals returned to the familiar environment. These results support increasing evidence for a functional distinction between the accumbal core and shell, with the latter having been linked to brain reward mechanisms. The results also indicate that novelty activates, albeit very transiently, some of the same neurochemical systems believed to play a critical role in the reinforcing effects of certain drugs of abuse.
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Affiliation(s)
- G V Rebec
- Department of Psychology, Indiana University, Bloomington 47405, U.S.A
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34
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Blaha CD. Evaluation of stearate-graphite paste electrodes for chronic measurement of extracellular dopamine concentrations in the mammalian brain. Pharmacol Biochem Behav 1996; 55:351-64. [PMID: 8951976 DOI: 10.1016/s0091-3057(96)00104-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Chronoamperometric procedures, in combination with pharmacological treatments, were used to verify whether stearate-modified graphite paste recording electrodes (SGEs) could measure basal extracellular dopamine (DA) concentrations in the striatum of awake rats over a 3-week period of implantation. Baseline chronoamperometric signals were unaffected by systemic injections of ascorbate (AA) or the monoamine oxidase inhibitor pargyline, or by intraventricular infusions of the AA degrading enzyme AA-oxidase. In contrast, systemic injections of d-amphetamine or nomifensine increased, and gamma-butyrolactone decreased, the signal in a reproducible fashion over a similar test period. In addition, 6-hydroxydopamine lesions of the nigrostriatal DA pathway attenuated the ability of d-amphetamine to increase, and gamma-butyrolactone to decrease, the chronoamperometric signal. In separate studies, reverse microdialysis, performed with dialysis probes implanted directly adjacent to SGEs in the striatum, permitted the assessment of electrode selectivity, sensitivity, response linearity, and detection limits to DA. Perfusion of the probe with normal Ringer solution (5 microliters/min) decreased the baseline chronoamperometric signal by 10 nA. Comparable decreases in the baseline signal were observed after systemic injections of gamma-butyrolactone or medial forebrain bundle infusions of tetrodotoxin, suggesting these decreases reflected depletion of extracellular DA to levels below the electrode's detection limit. Reverse dialysis with high concentrations of AA, DOPAC, 5-HT, or 5-HIAA, failed to reverse the decrease in the chronoamperometric signal induced by dialysis. In contrast, reverse dialysis with a physiologically relevant range of DA concentrations, in rats pretreated with the DA uptake blocker nomifensine, increased the chronoamperometric signal in a linear fashion with a detection threshold of < 20 nM. Combined, these results indicate that the baseline chronoamperometric signals recorded at +0.20 V in the striatum with SGEs do not reflect changes in extracellular concentrations of AA, DA metabolites, or indoles, but rather represent neuronally mediated nanomolar changes in extracellular DA concentrations, even after extended periods of implantation in brain tissue.
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Affiliation(s)
- C D Blaha
- Department of Psychology, University of British Columbia, Vancouver, Canada
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35
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Egan MF, Chrapusta S, Karoum F, Lipska BK, Wyatt RJ. Effects of chronic neuroleptic treatment on dopamine release: insights from studies using 3-methoxytyramine. J Neural Transm (Vienna) 1996; 103:777-805. [PMID: 8872864 DOI: 10.1007/bf01273358] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Antipsychotic medications appear to exert their therapeutic effects by blocking D2 receptors. While D2 blockade occurs rapidly, reduction in psychotic symptoms is often delayed. This time discrepancy has been attributed to the relatively slow development of depolarization inactivation (DI) of dopaminergic neurons. The reduced firing rates associated with DI has been hypothesized to reduce dopamine release and thus psychotic symptoms. Studies assessing changes in dopamine release during chronic neuroleptic treatment, using microdialysis and voltammetry, have been inconsistent. This may be due to methodological differences between studies, the invasive nature of these procedures, or other confounds. To investigate the effects of DI on dopamine release, 3-MT accumulation, an index of dopamine release that does not involve disruption of brain tissue, was measured during acute and chronic neuroleptic treatment. These results are compared with those using other techniques. 3-MT levels remained elevated after chronic treatment, suggesting that DI does not markedly reduce release. Regulation of dopamine release during DI was examined using two techniques known to block dopamine neuronal impulse flow. 3-MT levels were markedly reduced by both, implying that DI does not alter the portion of dopamine release mediated by neuronal impulse flow. Overall, studies to date suggest that the delayed therapeutic effects of neuroleptics are not due to reductions in impulse dependent dopamine release. Recent studies using a neurodevelopmental animal model of schizophrenia have pointed to altered pre- and post-synaptic indices of dopamine neurotransmission. The results suggest that neuroleptics may exert their therapeutic effects, in part, by limiting the fluctuations in dopamine release, and raise new issues for future research.
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Affiliation(s)
- M F Egan
- Neuropsychiatry Branche, National Institute of Mental Health, Neuroscience Research Center at St. Elizabeth's, Washington, DC, USA
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36
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Sreenivas G, Ang SS, Fritsch I, Brown WD, Gerhardt GA, Woodward DJ. Fabrication and Characterization of Sputtered-Carbon Microelectrode Arrays. Anal Chem 1996; 68:1858-64. [DOI: 10.1021/ac9508816] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- G. Sreenivas
- Departments of Electrical Engineering and Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, Departments of Pharmacology and Psychiatry and Rocky Mountain Center for Sensor Technology, University of Colorado Health Sciences Center, Denver, Colorado 80262, and Department of Physiology and Pharmacology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27157
| | - Simon S. Ang
- Departments of Electrical Engineering and Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, Departments of Pharmacology and Psychiatry and Rocky Mountain Center for Sensor Technology, University of Colorado Health Sciences Center, Denver, Colorado 80262, and Department of Physiology and Pharmacology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27157
| | - Ingrid Fritsch
- Departments of Electrical Engineering and Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, Departments of Pharmacology and Psychiatry and Rocky Mountain Center for Sensor Technology, University of Colorado Health Sciences Center, Denver, Colorado 80262, and Department of Physiology and Pharmacology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27157
| | - William D. Brown
- Departments of Electrical Engineering and Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, Departments of Pharmacology and Psychiatry and Rocky Mountain Center for Sensor Technology, University of Colorado Health Sciences Center, Denver, Colorado 80262, and Department of Physiology and Pharmacology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27157
| | - Greg A. Gerhardt
- Departments of Electrical Engineering and Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, Departments of Pharmacology and Psychiatry and Rocky Mountain Center for Sensor Technology, University of Colorado Health Sciences Center, Denver, Colorado 80262, and Department of Physiology and Pharmacology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27157
| | - Donald J. Woodward
- Departments of Electrical Engineering and Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, Departments of Pharmacology and Psychiatry and Rocky Mountain Center for Sensor Technology, University of Colorado Health Sciences Center, Denver, Colorado 80262, and Department of Physiology and Pharmacology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27157
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37
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Lönnrot K, Metsä-Ketelä T, Molnár G, Ahonen JP, Latvala M, Peltola J, Pietilä T, Alho H. The effect of ascorbate and ubiquinone supplementation on plasma and CSF total antioxidant capacity. Free Radic Biol Med 1996; 21:211-7. [PMID: 8818636 DOI: 10.1016/0891-5849(95)02207-4] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Free radicals are thought to be involved in the onset of neuronal disturbances such as Alzheimer's disease, Parkinson's disease, and neuronal ceroid lipofuscinosis. It is also assumed that they play a role in cerebral injury caused by ischemia or trauma. Plasma and cerebrospinal fluid (CSF), Total (peroxyl) Radical-trapping Antioxidant Parameter (TRAP), and the known antioxidant components of TRAP, for instance, ascorbic acid, uric acid, protein sulfhydryl groups, tocopherol, and ubiquinol were analyzed and the remaining unidentified fragment was calculated in five healthy volunteers before and after 4 weeks of ascorbate and ubiquinone (Q-10) supplementation. In CSF, TRAP was significantly lower than in plasma. The major contributor to plasma's antioxidant capacity was uric acid (UA), whereas in CSF it was ascorbic acid (AA). In CSF, AA concentrations were four times higher than in plasma. Oral supplementation of AA (500 mg/d first 2 weeks, 1,000 mg/d following 2 weeks) and Q-10 (100 mg/d first 2 weeks, 300 mg/d following 2 weeks) induced a significant increase in plasma AA and Q-10. Surprisingly, in spite of the high lipophilicity of Q-10, its concentration did not change in CSF. The supplementation of AA increased its concentration in CSF by 28% (p < .05). However, the increase in AA did not result in an increase in CSF TRAP. This indicates that AA had lost one-third of its radical trapping capacity as compared to that in plasma. The facts that AA is the highest contributor to CSF TRAP and its effect on TRAP is concentration dependent could indicate that the peroxyl radical-trapping capacity of CSF is buffered by AA.
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Affiliation(s)
- K Lönnrot
- Department of Biomedical Sciences, University of Tampere, Finland
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38
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Affiliation(s)
- H Katsuki
- Department of Chemical Pharmacology, University of Tokyo, Japan
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39
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Lada MW, Kennedy RT. Quantitative in vivo measurements using microdialysis on-line with capillary zone electrophoresis. J Neurosci Methods 1995; 63:147-52. [PMID: 8788059 DOI: 10.1016/0165-0270(95)00104-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A system which couples microdialysis with capillary zone electrophoresis (CZE) on-line is used to monitor ascorbate and lactate in the caudate nucleus of rat brain. On-line interface of microdialysis probe and electrophoresis capillary, along with the high mass sensitivity of CZE, allows the probe to be operated at flow rates as low as 40 nl/min. Under these conditions, the relative recovery is nearly 100% and quantitative monitoring is possible. The microscale system also facilitates calibration by the low flow rate method. In spite of the low flow rate, temporal resolution in the 45-125 s range is possible for these compounds. The system is demonstrated by observing changes in ascorbate due to infusions of elevated K+ through the dialysis probe and systemic injections of amphetamine and an anesthetic (ketamine/xylazine/acepromazine mixture). Lactate is monitored in response to elevated K+ infusions.
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Affiliation(s)
- M W Lada
- Department of Chemistry, University of Florida, Gainesville 32611, USA
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40
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Mason PA, Dev BR, Freed CR. Ascorbic acid concentration in the lateral hypothalamus is related to plasma osmolality. Brain Res Bull 1995; 37:305-9. [PMID: 7627575 DOI: 10.1016/0361-9230(95)00037-f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Microdialysis was used to measure extracellular ascorbic and uric acid concentrations in the lateral hypothalamus of water-restricted rats as they drank distilled water or 1.5% NaCl. Other water-restricted rats, not implanted with microdialysis probes, were decapitated 2 h after beginning to drink these fluids. Rats were inverted and their blood was collected for measurements of plasma osmolality and percent hematocrit. Results showed that drinking distilled water produced a significant increase in the ascorbic acid concentration but not in the uric acid concentration. Drinking 1.5% NaCl produced a significant decrease in the uric acid concentration but not in the ascorbic acid concentration. Drinking distilled water decreased mean osmolality from 306.0 to 291.5 mOsm/kg, whereas drinking 1.5% NaCl maintained mean osmolality at water-restricted levels. These results indicate that the extracellular fluid concentration of ascorbic acid in the lateral hypothalamus rises in response to a fall in plasma osmolality.
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Affiliation(s)
- P A Mason
- Department of Medicine, University of Colorado Health Sciences Center, Denver 80262, USA
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41
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Pierce RC, Clemens AJ, Shapiro LA, Rebec GV. Repeated treatment with ascorbate or haloperidol, but not clozapine, elevates extracellular ascorbate in the neostriatum of freely moving rats. Psychopharmacology (Berl) 1994; 116:103-9. [PMID: 7862921 DOI: 10.1007/bf02244879] [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: 01/27/2023]
Abstract
Acute administration of neuroleptic drugs alters the extracellular level of ascorbate in the neostriatum, and increasing evidence suggests a role for this vitamin in the behavioral, and possibly therapeutic, effects of these drugs. To shed further light on this issue, extracellular ascorbate was recorded in the neostriatum and nucleus accumbens of awake, behaving rats following chronic treatment with either classical (haloperidol) or atypical (clozapine) neuroleptics or ascorbate itself. Electrochemically modified, carbon-fiber microelectrodes were lowered in place the day after the last of 21 daily injections of either haloperidol (0.5 mg/kg, SC), clozapine (20 mg/kg, IP), sodium ascorbate (500 mg/kg, IP) or vehicle. Voltammetric measurements were obtained during quiet rest and following administration of d-amphetamine (2.5 mg/kg). Repeated treatment with either haloperidol or ascorbate elevated basal extracellular ascorbate and potentiated the amphetamine-induced increase in ascorbate release in neostriatum but not nucleus accumbens. Both treatment groups also showed a significant increase in amphetamine-induced sniffing and repetitive head movements compared to vehicle-treated animals. In contrast, repeated clozapine had no effect on extracellular ascorbate in either neostriatum or nucleus accumbens, but increased the locomotor response to an amphetamine challenge. Thus, to the extent that increases in neostriatal ascorbate exert neuroleptic-like effects, such effects are likely to parallel haloperidol rather than clozapine.
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Affiliation(s)
- R C Pierce
- Department of Psychology, Indiana University, Bloomington 47405
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42
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Rebec GV, Pierce RC. A vitamin as neuromodulator: ascorbate release into the extracellular fluid of the brain regulates dopaminergic and glutamatergic transmission. Prog Neurobiol 1994; 43:537-65. [PMID: 7816935 DOI: 10.1016/0301-0082(94)90052-3] [Citation(s) in RCA: 261] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Ascorbate is an antioxidant vitamin that the brain accumulates from the blood supply and maintains at a relatively high concentration under widely varying conditions. Although neurons are known to use this vitamin in many different chemical and enzymatic reactions, only recently has sufficient evidence emerged to suggest a role for ascorbate in interneuronal communication. Ascorbate is released from glutamatergic neurons as part of the glutamate reuptake process, in which the high-affinity glutamate transporter exchanges ascorbate for glutamate. This heteroexchange process, which also may occur in glial cells, ensures a relatively high level of extracellular ascorbate in many forebrain regions. Ascorbate release is regulated, at least in part, by dopaminergic mechanisms, which appear to involve both the D1 and D2 family of dopamine receptors. Thus, amphetamine, GBR-12909, apomorphine, and the combined administration of D1 and D2 agonists all facilitate ascorbate release from glutamatergic terminals in the neostriatum, and this effect is blocked by dopamine receptor antagonists. Even though the neostriatum itself contains a high concentration of dopamine receptors, the critical site for dopamine-mediated ascorbate release in the neostriatum is the substantia nigra. Intranigral dopamine regulates the activity of nigrothalamic efferents, which in turn regulate thalamocortical fibers and eventually the glutamatergic corticoneostriatal pathway. In addition, neostriatonigral fibers project to nigrothalamic efferents, completing a complex multisynaptic loop that plays a major role in neostriatal ascorbate release. Although extracellular ascorbate appears to modulate the synaptic action of dopamine, the mechanisms underlying this effect are unclear. Evidence from receptor binding studies suggests that ascorbate alters dopamine receptors either as an allosteric inhibitor or as an inducer of iron-dependent lipid peroxidation. The applicability of these studies to dopamine receptor function, however, remains to be established in view of reports that ascorbate can protect against lipid peroxidation in vivo. Nevertheless, ample behavioral evidence supports an antidopaminergic action of ascorbate. Systemic, intraventricular, or intraneostriatal ascorbate administration, for example, attenuates the behavioral effects of amphetamine and potentiates the behavioral response to haloperidol. Some of these behavioral effects, however, may be dose-dependent in that treatment with relatively low doses of ascorbate has been reported to enhance dopamine-mediated behaviors. Ascorbate also appears to modulate glutamatergic transmission in the neostriatum. In fact, by facilitating glutamate release, ascorbate may indirectly oppose the action of dopamine, though the nature of the neostriatal dopaminergic-glutamatergic interaction is far from settled. Ascorbate also may alter the redox state of the NMDA glutamate receptor thus block NMDA-gated channel function.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- G V Rebec
- Department of Psychology, Indiana University, Bloomington 47405
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43
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Liao BY, Lio HP, Wang CY, Young MS, Ho MT, Lin MT. A simplified method for selecting a carbon-fiber electrode in pulse voltammetry. J Neurosci Methods 1993; 50:291-9. [PMID: 8152240 DOI: 10.1016/0165-0270(93)90036-q] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A method for selecting a usable carbon-fiber electrode using the equivalent resistance and capacitance is presented. This method uses an instrument with a PC-based look-up table for measuring the electrical characteristics of a carbon-fiber electrode in pulse voltammetry. Using this instrument, the equivalent resistance and capacitance of the carbon-fiber electrode in saturated sodium chloride solution can be obtained. This instrument includes a decade resistance box, a peak current detection and hold circuit, a half peak comparator and a decay duration counter. A look-up table is established by using RC circuits to emulate the electrochemical reaction of the carbon-fiber electrode in pulse voltammetry. The equivalent resistance is obtained from the decade resistance box according to Kirchhoff's law. Then the equivalent capacitance is determined from the decay duration counter reading and equivalent resistance with the look-up table via a PC interpolation program. After obtaining the equivalent resistance and capacitance of an electrode, the values are compared with the usable thresholds. This method provides an effective quality evaluation index of carbon-fiber electrode for the user in order to reduce electrode-induced experimental failure. The method is also available for other kinds of carbon-fiber electrodes as long as their look-up table and desired thresholds are established.
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Affiliation(s)
- B Y Liao
- Department of Electrical Engineering, National Cheng Kung University, Tainan, Taiwan
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44
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Xing X, Bae IT, Shao M, Liu CC. Electro-oxidation of l-ascorbic acid on platinum in acid solutions: an in-situ FTIRRAS study. J Electroanal Chem (Lausanne) 1993. [DOI: 10.1016/0022-0728(93)85021-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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45
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Abstract
Ascorbic acid is highly concentrated in the central nervous system. Measurement of the extracellular concentration of ascorbate in animals, mainly by the technique of voltammetry in vivo, has demonstrated fluctuation in release from neuropil, both spontaneously and in response to physical stimulation of the animal and to certain drugs. Although in the adrenal medulla ascorbate is co-released with catecholamines, release of ascorbate from brain cells is associated principally with the activity of glutamatergic neurones, mainly by glutamate-ascorbate heteroexchange across cell membranes of neurones or glia. This phenomenon is discussed in relation to a possible role of ascorbate as a neuromodulator or neuroprotective agent in the brain.
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Affiliation(s)
- R A Grünewald
- Institute of Neurology, National Hospital for Neurology, London, UK
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46
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Pierce RC, Miller DW, Reising DB, Rebec GV. Unilateral neostriatal kainate, but not 6-OHDA, lesions block dopamine agonist-induced ascorbate release in the neostriatum of freely moving rats. Brain Res 1992; 597:138-43. [PMID: 1477726 DOI: 10.1016/0006-8993(92)91515-g] [Citation(s) in RCA: 16] [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
Unilateral kainate lesions of the neostriatum and 6-hydroxydopamine (6-OHDA) lesions of the medial forebrain bundle were used to assess the role of neostriatal and ascending dopaminergic neurons, respectively, on dopamine-agonist induced release of neostriatal ascorbate as measured voltammetrically in freely moving rats. Electrochemically modified, carbon-fiber electrodes recorded the effects of direct (a combination of 10 mg/kg SKF-38393 and 1.0 mg/kg quinpirole) as well as indirect (2.5 mg/kg D-amphetamine or 20.0 mg/kg GBR-12909) dopamine agonists. Relative to controls, kainate, but not 6-OHDA, lesions abolished the ability of both direct and indirect dopamine agonists to induce neostriatal ascorbate release. These results suggest that unlike dopaminergic afferents, neostriatal output pathways play a critical role in the modulation of neostriatal ascorbate levels.
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Affiliation(s)
- R C Pierce
- Department of Psychology, Indiana University, Bloomington 47405
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47
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Xing X, Shao M, Hsiao M, Adzic R, Liu CC. Structural effects in electrocatalysis: electro-oxidation of l-ascorbic acid on single-crystal gold surfaces. J Electroanal Chem (Lausanne) 1992. [DOI: 10.1016/0022-0728(92)80453-b] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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48
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Pierce RC, Rebec GV. Dopamine-, NMDA- and sigma-receptor antagonists exert differential effects on basal and amphetamine-induced changes in neostriatal ascorbate and DOPAC in awake, behaving rats. Brain Res 1992; 579:59-66. [PMID: 1352478 DOI: 10.1016/0006-8993(92)90741-q] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Amphetamine and other dopamine agonists elevate the extracellular level of neostriatal ascorbate, which has been shown to modulate neuronal function. To assess the receptor mechanisms underlying neostriatal ascorbate release, drug-induced changes in both basal and amphetamine-induced ascorbate release were monitored voltammetrically in the neostriatum of freely moving rats. A variety of dopamine receptor antagonists decreased basal ascorbate and reversed the increase induced by 2.5 mg/kg D-amphetamine. Thus, compared to vehicle treatment, administration of classical (haloperidol) and atypical (clozapine) neuroleptics or selective D1 (SCH-23390) and D2 (sulpiride) antagonists completely reversed the amphetamine-induced rise in ascorbate and also lowered basal levels by 20-40%. These same effects occurred following injection of dizocilpine (MK-801), a non-competitive NMDA antagonist, whereas BMY-14802, a sigma ligand, reversed the amphetamine-induced rise without altering basal levels. Simultaneous measurements of extracellular DOPAC, a major dopamine metabolite, revealed that haloperidol, clozapine, sulpiride and BMY-14802 elevated basal levels and reversed the amphetamine-induced decline. Dizocilpine also increased basal DOPAC but failed to alter the DOPAC response to amphetamine, whereas both basal and amphetamine-induced changes in DOPAC were unaffected by SCH-23390. A combination of subthreshold doses of SCH-23390 and sulpiride, however, reversed both the amphetamine-induced release of ascorbate and the corresponding decline in DOPAC. Collectively, these results suggest that whereas dopamine, sigma, and NMDA receptors modulate neostriatal ascorbate release, they exert an opposing influence on extracellular DOPAC. All drugs attenuated at least some components of the amphetamine behavioral response, suggesting a role for multiple mechanisms in the behavioral effects of this drug.
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Affiliation(s)
- R C Pierce
- Department of Psychology, Indiana University, Bloomington 47405
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49
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Kissinger PT. The development of liquid chromatography/electrochemistry from a historical perspective. ELECTROANAL 1992. [DOI: 10.1002/elan.1140040403] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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50
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Electrochemical oxidation ofL-ascorbic acid at the graphite electrode and its monitoring by a thick-film graphite sensor assembly. ELECTROANAL 1992. [DOI: 10.1002/elan.1140040209] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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