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González Brito R, Montenegro P, Méndez A, Shabgahi RE, Pasquarelli A, Borges R. Analytical Determination of Serotonin Exocytosis in Human Platelets with BDD-on-Quartz MEA Devices. BIOSENSORS 2024; 14:75. [PMID: 38391994 PMCID: PMC10886747 DOI: 10.3390/bios14020075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/26/2024] [Accepted: 01/29/2024] [Indexed: 02/24/2024]
Abstract
Amperometry is arguably the most widely used technique for studying the exocytosis of biological amines. However, the scarcity of human tissues, particularly in the context of neurological diseases, poses a challenge for exocytosis research. Human platelets, which accumulate 90% of blood serotonin, release it through exocytosis. Nevertheless, single-cell amperometry with encapsulated carbon fibers is impractical due to the small size of platelets and the limited number of secretory granules on each platelet. The recent technological improvements in amperometric multi-electrode array (MEA) devices allow simultaneous recordings from several high-performance electrodes. In this paper, we present a comparison of three MEA boron-doped diamond (BDD) devices for studying serotonin exocytosis in human platelets: (i) the BDD-on-glass MEA, (ii) the BDD-on-silicon MEA, and (iii) the BDD on amorphous quartz MEA (BDD-on-quartz MEA). Transparent electrodes offer several advantages for observing living cells, and in the case of platelets, they control activation/aggregation. BDD-on-quartz offers the advantage over previous materials of combining excellent electrochemical properties with transparency for microscopic observation. These devices are opening exciting perspectives for clinical applications.
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Affiliation(s)
- Rosalía González Brito
- Pharmacology Unit, Medical School, Universidad de La Laguna, 38200 La Laguna, Spain; (R.G.B.); (P.M.); (A.M.)
| | - Pablo Montenegro
- Pharmacology Unit, Medical School, Universidad de La Laguna, 38200 La Laguna, Spain; (R.G.B.); (P.M.); (A.M.)
| | - Alicia Méndez
- Pharmacology Unit, Medical School, Universidad de La Laguna, 38200 La Laguna, Spain; (R.G.B.); (P.M.); (A.M.)
| | - Ramtin E. Shabgahi
- Institute of Electron Devices and Circuits, Ulm University, 89069 Ulm, Germany; (R.E.S.); (A.P.)
| | - Alberto Pasquarelli
- Institute of Electron Devices and Circuits, Ulm University, 89069 Ulm, Germany; (R.E.S.); (A.P.)
| | - Ricardo Borges
- Pharmacology Unit, Medical School, Universidad de La Laguna, 38200 La Laguna, Spain; (R.G.B.); (P.M.); (A.M.)
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2
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Borges R, Gu C, Machado JD, Ewing AG. The dynamic nature of exocytosis from large secretory vesicles. A view from electrochemistry and imaging. Cell Calcium 2023; 110:102699. [PMID: 36708611 DOI: 10.1016/j.ceca.2023.102699] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/16/2023] [Accepted: 01/19/2023] [Indexed: 01/22/2023]
Abstract
In this brief review, we discuss the factors that modulate the quantum size and the kinetics of exocytosis. We also discuss the determinants which motivate the type of exocytosis from the so-called kiss-and-run to full fusion and along the intermediate mode of partial release. Kiss-and-run release comprises the transient opening of a nanometer (approx. 2 nm diameter) fusion pore between vesicle and plasma membrane allowing a small amount of release. Partial release comprises a larger more extended opening of the pore to allow a larger fraction of released vesicle content and is what is observed as normal full release in most electrochemical measurements. Partial release appears to be dominant in dense core vesicles and perhaps synaptic vesicles. The concept of partial release leads to the fraction released as a plastic component of exocytosis. Partial vesicular distension and the kinetics of exocytosis can be modulated by second messengers, physiological modulators, and drugs. This concept adds a novel point of regulation for the exocytotic process.
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Affiliation(s)
- Ricardo Borges
- Pharmacology Unit, Medical School, Universidad de la Laguna, Tenerife. Spain
| | - Chaoyi Gu
- Department of Chemistry and Molecular Biology, University of Gothenburg, Sweden
| | - José-David Machado
- Pharmacology Unit, Medical School, Universidad de la Laguna, Tenerife. Spain
| | - Andrew G Ewing
- Department of Chemistry and Molecular Biology, University of Gothenburg, Sweden.
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3
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Yakovleva O, Albova P, Sitdikova G. The Role of Nitric Oxide in Regulation of Exocytosis and Endocytosis of Synaptic Vesicles in Motor Nerve Endings of Mice in Alloxan Model of Diabetes Mellitus. BIONANOSCIENCE 2022. [DOI: 10.1007/s12668-022-00976-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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4
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Sensitive detection of electrophysiology and dopamine vesicular exocytosis of hESC-Derived dopaminergic neurons using multifunctional microelectrode array. Biosens Bioelectron 2022; 209:114263. [DOI: 10.1016/j.bios.2022.114263] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Revised: 02/24/2022] [Accepted: 04/06/2022] [Indexed: 12/30/2022]
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5
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Glucagon-like peptide-1 receptor controls exocytosis in chromaffin cells by increasing full-fusion events. Cell Rep 2021; 36:109609. [PMID: 34433018 DOI: 10.1016/j.celrep.2021.109609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 07/02/2021] [Accepted: 08/04/2021] [Indexed: 11/21/2022] Open
Abstract
Agonists for glucagon-like-peptide-1 receptor (GLP-1R) are currently used for the treatment of type 2 diabetes and obesity. Their benefits have been centered on pancreas and hypothalamus, but their roles in other organ systems are not well understood. We studied the action of GLP-1R on secretions of adrenal medulla. Exendin-4, a synthetic analog of GLP-1, increases the synthesis and the release of catecholamines (CAs) by increasing cyclic AMP (cAMP) production, without apparent participation of cAMP-regulated guanine nucleotide exchange factor (Epac). Exendin-4, when incubated for 24 h, increases CA synthesis by promoting the activation of tyrosine hydroxylase. Short incubation (20 min) increases the quantum size of exocytotic events by switching exocytosis from partial to full fusion. Our results give a strong support to the role of GLP-1 in the fine control of exocytosis.
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6
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Chronic resveratrol consumption prevents hypertension development altering electrophysiological currents and Ca 2+ signaling in chromaffin cells from SHR rats. Cell Signal 2020; 76:109811. [PMID: 33075487 DOI: 10.1016/j.cellsig.2020.109811] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 10/12/2020] [Accepted: 10/14/2020] [Indexed: 12/31/2022]
Abstract
Resveratrol (RESV) is one of the most abundant polyphenol-stilbene compounds found in red wine with well-established cardioprotective and antihypertensive effects. Hyperactivity of the sympathoadrenal axis seems to be one of the major contributing factors in the pathogenesis of human essential hypertension. Alterations in outward voltage-dependent potassium currents (IK) and inward voltage-dependent sodium (INa), calcium (ICa) and nicotinic (IACh) currents, CCs excitability, Ca2+ homeostasis, and catecholamine exocytosis were previously related to the hypertensive state. This raised the issue of whether in vivo long-term RESV treatment can directly act as a modulator of Ca2+ influx or a regulator of ion channel permeability in CCs. We monitored outward and inward currents, and cytosolic Ca2+ concentrations ([Ca2+]c) using different pharmacological approaches in CCs from normotensive (WKY) and hypertensive (SHR) animals chronically exposed to trans-RESV (50 mg/L/v.o, 28 days). The long-term RESV treatment prevented the increase of the systolic blood pressure (SBP) in SHR, without reversion of cardiac hypertrophy. We also found an increase of the outward IK, reduction in inward INa,ICa, and IACh, and the mitigation of [Ca2+]c overload in CCs from SHR at the end of RESV treatment. Our data revealed that electrophysiological alterations of the CCs and in its Ca2+ homeostasis are potential new targets related to the antihypertensive effects of long-term RESV treatment.
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Tsutsuki H, Kasamatsu S, Kunieda K, Ida T, Sawa T, Sasakawa N, Akaike T, Ihara H. 8-Nitro-cGMP modulates exocytosis in adrenal chromaffin cells. Biochem Biophys Res Commun 2020; 526:225-230. [PMID: 32201073 DOI: 10.1016/j.bbrc.2020.03.045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 03/08/2020] [Indexed: 12/21/2022]
Abstract
Nitric oxide (NO)-mediated production of cyclic guanosine 3',5'-monophosphate (cGMP) is a crucial signaling pathway that controls a wide array of neuronal functions, including exocytotic neurotransmitter release. A novel nitrated derivative of cGMP, 8-nitro-cGMP, not only activates cGMP-dependent protein kinase (PKG), but also has membrane permeability and redox activity to produce superoxide and S-guanylated protein. To date, no studies have addressed the effects of 8-nitro-cGMP on exocytotic kinetics. Here, we aimed to assess the 8-nitro-cGMP-mediated modulation of the depolarization-evoked catecholamine release from bovine chromaffin cells. 8-Nitro-cGMP was produced in bovine chromaffin cells dependent on NO donor. Amperometric analysis revealed that 8-nitro-cGMP modulated the kinetic parameters of secretory spikes from chromaffin cells, particularly decreased the speed of individual spikes, resulting in a reduced amperometric spike height, slope β, and absolute value of slope γ. The modulatory effects were independent of the PKG signal and superoxide production. This is the first study to demonstrate that 8-nitro-cGMP modulates exocytosis and provide insights into a novel regulatory mechanism of exocytosis.
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Affiliation(s)
- Hiroyasu Tsutsuki
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, 860-8556, Japan
| | - Shingo Kasamatsu
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Osaka, 599-8531, Japan
| | - Kohei Kunieda
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Osaka, 599-8531, Japan
| | - Tomoaki Ida
- Departments of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, 980-8575, Japan
| | - Tomohiro Sawa
- Department of Microbiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, 860-8556, Japan
| | - Nobuyuki Sasakawa
- Department of Information and Communication Sciences, Faculty of Science and Technology, Sophia University, Tokyo, 102-8554, Japan
| | - Takaaki Akaike
- Departments of Environmental Medicine and Molecular Toxicology, Tohoku University Graduate School of Medicine, Sendai, 980-8575, Japan
| | - Hideshi Ihara
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Osaka, 599-8531, Japan.
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8
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Galkina SI, Fedorova NV, Golenkina EA, Stadnichuk VI, Sud’ina GF. Cytonemes Versus Neutrophil Extracellular Traps in the Fight of Neutrophils with Microbes. Int J Mol Sci 2020; 21:ijms21020586. [PMID: 31963289 PMCID: PMC7014225 DOI: 10.3390/ijms21020586] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/09/2020] [Accepted: 01/10/2020] [Indexed: 12/11/2022] Open
Abstract
Neutrophils can phagocytose microorganisms and destroy them intracellularly using special bactericides located in intracellular granules. Recent evidence suggests that neutrophils can catch and kill pathogens extracellularly using the same bactericidal agents. For this, live neutrophils create a cytoneme network, and dead neutrophils provide chromatin and proteins to form neutrophil extracellular traps (NETs). Cytonemes are filamentous tubulovesicular secretory protrusions of living neutrophils with intact nuclei. Granular bactericides are localized in membrane vesicles and tubules of which cytonemes are composed. NETs are strands of decondensed DNA associated with histones released by died neutrophils. In NETs, bactericidal neutrophilic agents are adsorbed onto DNA strands and are not covered with a membrane. Cytonemes and NETs occupy different places in protecting the body against infections. Cytonemes can develop within a few minutes at the site of infection through the action of nitric oxide or actin-depolymerizing alkaloids of invading microbes. The formation of NET in vitro occurs due to chromatin decondensation resulting from prolonged activation of neutrophils with PMA (phorbol 12-myristate 13-acetate) or other stimuli, or in vivo due to citrullination of histones with peptidylarginine deiminase 4. In addition to antibacterial activity, cytonemes are involved in cell adhesion and communications. NETs play a role in autoimmunity and thrombosis.
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Affiliation(s)
- Svetlana I. Galkina
- Lomonosov Moscow State University, A. N. Belozersky Institute of Physico-Chemical Biology, 119991 Moscow, Russia; (N.V.F.); (E.A.G.)
- Correspondence: (S.I.G.); (G.F.S.); Tel.: +7-495-939-5408 (S.I.G.)
| | - Natalia V. Fedorova
- Lomonosov Moscow State University, A. N. Belozersky Institute of Physico-Chemical Biology, 119991 Moscow, Russia; (N.V.F.); (E.A.G.)
| | - Ekaterina A. Golenkina
- Lomonosov Moscow State University, A. N. Belozersky Institute of Physico-Chemical Biology, 119991 Moscow, Russia; (N.V.F.); (E.A.G.)
| | | | - Galina F. Sud’ina
- Lomonosov Moscow State University, A. N. Belozersky Institute of Physico-Chemical Biology, 119991 Moscow, Russia; (N.V.F.); (E.A.G.)
- Correspondence: (S.I.G.); (G.F.S.); Tel.: +7-495-939-5408 (S.I.G.)
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9
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de Diego AMG, García AG. Altered exocytosis in chromaffin cells from mouse models of neurodegenerative diseases. Acta Physiol (Oxf) 2018; 224:e13090. [PMID: 29742321 DOI: 10.1111/apha.13090] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 04/19/2018] [Accepted: 04/25/2018] [Indexed: 12/26/2022]
Abstract
Chromaffin cells from the adrenal gland (CCs) have extensively been used to explore the molecular structure and function of the exocytotic machinery, neurotransmitter release and synaptic transmission. The CC is integrated in the sympathoadrenal axis that helps the body maintain homoeostasis during both routine life and in acute stress conditions. This function is exquisitely controlled by the cerebral cortex and the hypothalamus. We propose the hypothesis that damage undergone by the brain during neurodegenerative diseases is also affecting the neurosecretory function of adrenal medullary CCs. In this context, we review here the following themes: (i) How the discharge of catecholamines is centrally and peripherally regulated at the sympathoadrenal axis; (ii) which are the intricacies of the amperometric techniques used to study the quantal release of single-vesicle exocytotic events; (iii) which are the alterations of the exocytotic fusion pore so far reported, in CCs of mouse models of neurodegenerative diseases; (iv) how some proteins linked to neurodegenerative pathologies affect the kinetics of exocytotic events; (v) finally, we try to integrate available data into a hypothesis to explain how the centrally originated neurodegenerative diseases may alter the kinetics of single-vesicle exocytotic events in peripheral adrenal medullary CCs.
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Affiliation(s)
- A. M. García de Diego
- Instituto Teófilo Hernando; Universidad Autónoma de Madrid; Madrid Spain
- Instituto de Investigación Sanitaria; Hospital Universitario de la Princesa; Universidad Autónoma de Madrid; Madrid Spain
- DNS Neuroscience; Parque Científico de Madrid; Madrid Spain
| | - A. García García
- Instituto Teófilo Hernando; Universidad Autónoma de Madrid; Madrid Spain
- Instituto de Investigación Sanitaria; Hospital Universitario de la Princesa; Universidad Autónoma de Madrid; Madrid Spain
- DNS Neuroscience; Parque Científico de Madrid; Madrid Spain
- Departamento de Farmacología y Terapéutica; Facultad de Medicina; Universidad Autónoma de Madrid; Madrid Spain
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10
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Baraibar AM, de Pascual R, Camacho M, Domínguez N, David Machado J, Gandía L, Borges R. Distinct patterns of exocytosis elicited by Ca 2+, Sr 2+ and Ba 2+ in bovine chromaffin cells. Pflugers Arch 2018; 470:1459-1471. [PMID: 29926228 DOI: 10.1007/s00424-018-2166-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 05/24/2018] [Accepted: 06/07/2018] [Indexed: 10/28/2022]
Abstract
Three divalent cations can elicit secretory responses in most neuroendocrine cells, including chromaffin cells. The extent to which secretion is elicited by the cations in intact depolarized cells was Ba2+ > Sr2+ ≥ Ca2+, contrasting with that elicited by these cations in permeabilized cells (Ca2+ > Sr2+ > Ba2+). Current-clamp recordings show that extracellular Sr2+ and Ba2+ cause membrane depolarization and action potentials, which are not blocked by Cd2+ but that can be mimicked by tetra-ethyl-ammonium. When applied intracellularly, only Ba2+ provokes action potentials. Voltage-clamp monitoring of Ca2+-activated K+ channels (KCa) shows that Ba2+ reduces outward currents, which were enhanced by Sr2+. Extracellular Ba2+ increases cytosolic Ca2+ concentrations in Fura-2-loaded intact cells, and it induces long-lasting catecholamine release. Conversely, amperometric recordings of permeabilized cells show that Ca2+ promotes the longest lasting secretion, as Ba2+ only provokes secretion while it is present and Sr2+ induces intermediate-lasting secretion. Intracellular Ba2+ dialysis provokes exocytosis at concentrations 100-fold higher than those of Ca2+, whereas Sr2+ exhibits an intermediate sensitivity. These results are compatible with the following sequence of events: Ba2+ blocks KCa channels from both the outside and inside of the cell, causing membrane depolarization that, in turn, opens voltage-sensitive Ca2+ channels and favors the entry of Ca2+ and Ba2+. Although Ca2+ is less permeable through its own channels, it is more efficient in triggering exocytosis. Strontium possesses both an intermediate permeability and an intermediate ability to induce secretion.
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Affiliation(s)
- Andrés M Baraibar
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Arzobispo Morcillo 4, 28029, Madrid, Spain
| | - Ricardo de Pascual
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Arzobispo Morcillo 4, 28029, Madrid, Spain
| | - Marcial Camacho
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, 38200, La Laguna, Tenerife, Spain.,Institute of Neurophysiology, Charité-Universitätsmedizin Berlin, 10117, Berlin, Germany
| | - Natalia Domínguez
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, 38200, La Laguna, Tenerife, Spain.,INTEGRARE, Généthon, Inserm, Univ Evry, Université Paris-Saclay, 91002, Evry, France
| | - J David Machado
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, 38200, La Laguna, Tenerife, Spain
| | - Luis Gandía
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, Arzobispo Morcillo 4, 28029, Madrid, Spain
| | - Ricardo Borges
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, 38200, La Laguna, Tenerife, Spain. .,Instituto Universitario de BioOrgánica Antonio González, Universidad de La Laguna, 38200, La Laguna, Tenerife, Spain.
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11
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Hydrogen sulphide facilitates exocytosis by regulating the handling of intracellular calcium by chromaffin cells. Pflugers Arch 2018; 470:1255-1270. [DOI: 10.1007/s00424-018-2147-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 04/10/2018] [Accepted: 04/17/2018] [Indexed: 01/09/2023]
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12
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Old and emerging concepts on adrenal chromaffin cell stimulus-secretion coupling. Pflugers Arch 2017; 470:1-6. [PMID: 29110079 DOI: 10.1007/s00424-017-2082-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Accepted: 10/19/2017] [Indexed: 10/18/2022]
Abstract
The chromaffin cells (CCs) of the adrenal medulla play a key role in the control of circulating catecholamines to adapt our body function to stressful conditions. A huge research effort over the last 35 years has converted these cells into the Escherichia coli of neurobiology. CCs have been the testing bench for the development of patch-clamp and amperometric recording techniques and helped clarify most of the known molecular mechanisms that regulate cell excitability, Ca2+ signals associated with secretion, and the molecular apparatus that regulates vesicle fusion. This special issue provides a state-of-the-art on the many well-known and unsolved questions related to the molecular processes at the basis of CC function. The issue is also the occasion to highlight the seminal work of Antonio G. García (Emeritus Professor at UAM, Madrid) who greatly contributed to the advancement of our present knowledge on CC physiology and pharmacology. All the contributors of the present issue are distinguished scientists who are either staff members, external collaborators, or friends of Prof. García.
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13
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How intravesicular composition affects exocytosis. Pflugers Arch 2017; 470:135-141. [PMID: 28779472 DOI: 10.1007/s00424-017-2035-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 07/11/2017] [Accepted: 07/12/2017] [Indexed: 12/26/2022]
Abstract
Large dense core vesicles and chromaffin granules accumulate solutes at large concentrations (for instance, catecholamines, 0.5-1 M; ATP, 120-300 mM; or Ca2+, 40 mM (12)). Solutes seem to aggregate to a condensed protein matrix, which is mainly composed of chromogranins, to elude osmotic lysis. This association is also responsible for the delayed release of catecholamines during exocytosis. Here, we compile experimental evidence, obtained since the inception of single-cell amperometry, demonstrating how the alteration of intravesicular composition promotes changes in the quantum characteristics of exocytosis. As chromaffin cells are large and their vesicles contain a high concentration of electrochemically detectable species, most experimental data comes from this cell model.
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14
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Duvoor C, Dendi VS, Marco A, Shekhawat NS, Chada A, Ravilla R, Musham CK, Mirza W, Chaudhury A. Commentary: ATP: The crucial component of secretory vesicles: Accelerated ATP/insulin exocytosis and prediabetes. Front Physiol 2017; 8:53. [PMID: 28210227 PMCID: PMC5288386 DOI: 10.3389/fphys.2017.00053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 01/19/2017] [Indexed: 02/03/2023] Open
Affiliation(s)
- Chitharanjan Duvoor
- Department of Endocrinology and Internal Medicine, University of Arkansas for Medical SciencesLittle Rock, AR, USA; GIM FoundationLittle Rock, AR, USA
| | - Vijaya S Dendi
- GIM FoundationLittle Rock, AR, USA; Department of Internal Medicine and Hospital Medicine, Christus Trinity Mother Frances HospitalTyler, TX, USA
| | - Asween Marco
- GIM FoundationLittle Rock, AR, USA; Department of Policy, University of Arkansas for Little RockLittle Rock, AR, USA
| | - Nawal S Shekhawat
- GIM FoundationLittle Rock, AR, USA; Tutwiler ClinicTutwiler, MS, USA
| | - Aditya Chada
- GIM FoundationLittle Rock, AR, USA; Department of Pulmonary and Critical Care Medicine, University of Arkansas for Medical SciencesLittle Rock, AR, USA
| | - Rahul Ravilla
- GIM FoundationLittle Rock, AR, USA; Winthrop P. Rockefeller Cancer Institute, University of Arkansas for Medical SciencesLittle Rock, AR, USA
| | - Chaitanya K Musham
- GIM FoundationLittle Rock, AR, USA; St. Vincent Infirmary (Catholic Health Initiative)Little Rock, AR, USA
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15
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Estévez-Herrera J, Domínguez N, Pardo MR, González-Santana A, Westhead EW, Borges R, Machado JD. ATP: The crucial component of secretory vesicles. Proc Natl Acad Sci U S A 2016; 113:E4098-106. [PMID: 27342860 PMCID: PMC4948319 DOI: 10.1073/pnas.1600690113] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The colligative properties of ATP and catecholamines demonstrated in vitro are thought to be responsible for the extraordinary accumulation of solutes inside chromaffin cell secretory vesicles, although this has yet to be demonstrated in living cells. Because functional cells cannot be deprived of ATP, we have knocked down the expression of the vesicular nucleotide carrier, the VNUT, to show that a reduction in vesicular ATP is accompanied by a drastic fall in the quantal release of catecholamines. This phenomenon is particularly evident in newly synthesized vesicles, which we show are the first to be released. Surprisingly, we find that inhibiting VNUT expression also reduces the frequency of exocytosis, whereas the overexpression of VNUT drastically increases the quantal size of exocytotic events. To our knowledge, our data provide the first demonstration that ATP, in addition to serving as an energy source and purinergic transmitter, is an essential element in the concentration of catecholamines in secretory vesicles. In this way, cells can use ATP to accumulate neurotransmitters and other secreted substances at high concentrations, supporting quantal transmission.
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Affiliation(s)
- Judith Estévez-Herrera
- Unidad de Farmacología, Facultad de Medicina, Universidad de la Laguna, Tenerife 38320, Spain
| | - Natalia Domínguez
- Unidad de Farmacología, Facultad de Medicina, Universidad de la Laguna, Tenerife 38320, Spain
| | - Marta R Pardo
- Unidad de Farmacología, Facultad de Medicina, Universidad de la Laguna, Tenerife 38320, Spain; Instituto Universitario de Bio-Orgánica 'Antonio González', Universidad de la Laguna, Tenerife 38320, Spain
| | - Ayoze González-Santana
- Unidad de Farmacología, Facultad de Medicina, Universidad de la Laguna, Tenerife 38320, Spain
| | - Edward W Westhead
- Unidad de Farmacología, Facultad de Medicina, Universidad de la Laguna, Tenerife 38320, Spain
| | - Ricardo Borges
- Unidad de Farmacología, Facultad de Medicina, Universidad de la Laguna, Tenerife 38320, Spain; Instituto Universitario de Bio-Orgánica 'Antonio González', Universidad de la Laguna, Tenerife 38320, Spain
| | - José David Machado
- Unidad de Farmacología, Facultad de Medicina, Universidad de la Laguna, Tenerife 38320, Spain
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Galkina SI, Fedorova NV, Serebryakova MV, Arifulin EA, Stadnichuk VI, Gaponova TV, Baratova LA, Sud'ina GF. Inhibition of the GTPase dynamin or actin depolymerisation initiates outward plasma membrane tubulation/vesiculation (cytoneme formation) in neutrophils. Biol Cell 2015; 107:144-58. [DOI: 10.1111/boc.201400063] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 01/29/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Svetlana I. Galkina
- A. N. Belozersky Institute of Physico-Chemical Biology; Lomonosov Moscow State University; Moscow 119991 Russia
| | - Natalia V. Fedorova
- A. N. Belozersky Institute of Physico-Chemical Biology; Lomonosov Moscow State University; Moscow 119991 Russia
| | - Marina V. Serebryakova
- A. N. Belozersky Institute of Physico-Chemical Biology; Lomonosov Moscow State University; Moscow 119991 Russia
| | - Evgenii A. Arifulin
- A. N. Belozersky Institute of Physico-Chemical Biology; Lomonosov Moscow State University; Moscow 119991 Russia
| | | | - Tatjana V. Gaponova
- FGBU Hematology Research Center; Russian Federation Ministry of Public Health; Moscow 125167 Russia
| | - Ludmila A. Baratova
- A. N. Belozersky Institute of Physico-Chemical Biology; Lomonosov Moscow State University; Moscow 119991 Russia
| | - Galina F. Sud'ina
- A. N. Belozersky Institute of Physico-Chemical Biology; Lomonosov Moscow State University; Moscow 119991 Russia
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17
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Calvo-Gallardo E, de Pascual R, Fernández-Morales JC, Arranz-Tagarro JA, Maroto M, Nanclares C, Gandía L, de Diego AMG, Padín JF, García AG. Depressed excitability and ion currents linked to slow exocytotic fusion pore in chromaffin cells of the SOD1(G93A) mouse model of amyotrophic lateral sclerosis. Am J Physiol Cell Physiol 2014; 308:C1-19. [PMID: 25377090 DOI: 10.1152/ajpcell.00272.2014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Altered synaptic transmission with excess glutamate release has been implicated in the loss of motoneurons occurring in amyotrophic lateral sclerosis (ALS). Hyperexcitability or hypoexcitability of motoneurons from mice carrying the ALS mutation SOD1(G93A) (mSOD1) has also been reported. Here we have investigated the excitability, the ion currents, and the kinetics of the exocytotic fusion pore in chromaffin cells from postnatal day 90 to postnatal day 130 mSOD1 mice, when motor deficits are already established. With respect to wild-type (WT), mSOD1 chromaffin cells had a decrease in the following parameters: 95% in spontaneous action potentials, 70% in nicotinic current for acetylcholine (ACh), 35% in Na(+) current, 40% in Ca(2+)-dependent K(+) current, and 53% in voltage-dependent K(+) current. Ca(2+) current was increased by 37%, but the ACh-evoked elevation of cytosolic Ca(2+) was unchanged. Single exocytotic spike events triggered by ACh had the following differences (mSOD1 vs. WT): 36% lower rise rate, 60% higher decay time, 51% higher half-width, 13% lower amplitude, and 61% higher quantal size. The expression of the α3-subtype of nicotinic receptors and proteins of the exocytotic machinery was unchanged in the brain and adrenal medulla of mSOD1, with respect to WT mice. A slower fusion pore opening, expansion, and closure are likely linked to the pronounced reduction in cell excitability and in the ion currents driving action potentials in mSOD1, compared with WT chromaffin cells.
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Affiliation(s)
| | - Ricardo de Pascual
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, Madrid, Spain; Departamento de Farmacología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | | | | | - Marcos Maroto
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, Madrid, Spain
| | - Carmen Nanclares
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, Madrid, Spain
| | - Luis Gandía
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, Madrid, Spain; Departamento de Farmacología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | | | - Juan-Fernando Padín
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, Madrid, Spain; Departamento de Farmacología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - Antonio G García
- Instituto Teófilo Hernando, Universidad Autónoma de Madrid, Madrid, Spain; Departamento de Farmacología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain; Servicio de Farmacología Clínica, Hospital Universitario de La Princesa, Madrid, Spain; and Instituto de Investigación Sanitaria, Hospital Universitario de La Princesa, Madrid, Spain
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18
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Dominguez N, Estevez-Herrera J, Borges R, Machado JD. The interaction between chromogranin A and catecholamines governs exocytosis. FASEB J 2014; 28:4657-67. [PMID: 25077558 DOI: 10.1096/fj.14-249607] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Chromogranins (Cgs) are acidic proteins that have been described in the large, dense core vesicles (LDCVs) of adrenal chromaffin cells and that have been shown to promote LDCV formation, even in nonsecretory cells. Catecholamines (CAs) are adsorbed by Cgs in vitro, and the absence of Cgs modifies the storage and exocytosis of CAs in chromaffin cells. In this study, we set out to assess the role of CgA in the accumulation and exocytosis of CAs in cells when the levels of CgA and CA are manipulated. We overexpressed CgA in nonsecretory HEK293 cells and in secretory PC12 cells, to study the formation, movement, and exocytosis of newly formed granules by evanescent wave microscopy. We analyzed the association of Cgs/CA by HPLC and amperometry and their role in the accumulation and exocytosis of amines, both under resting conditions and after l-DOPA overloading. To our knowledge, this is the first demonstration that CgA expression in a nonsecretory cell line facilitates the storage and exocytosis of CA. In addition, CgA overexpression causes a doubling of the accumulation of CA, although it slows down exocytosis in PC12 cells. We propose a model to explain how the CgA/CA complex governs the accumulation and exocytosis of secreted amines.
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Affiliation(s)
- Natalia Dominguez
- Unidad de Farmacologia, Facultad de Medicina, Universidad de La Laguna, Tenerife, Spain
| | | | - Ricardo Borges
- Unidad de Farmacologia, Facultad de Medicina, Universidad de La Laguna, Tenerife, Spain
| | - Jose D Machado
- Unidad de Farmacologia, Facultad de Medicina, Universidad de La Laguna, Tenerife, Spain
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19
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Izquierdo-Serra M, Trauner D, Llobet A, Gorostiza P. Optical control of calcium-regulated exocytosis. Biochim Biophys Acta Gen Subj 2013. [PMID: 23178861 DOI: 10.1016/j.bbagen.2012.11.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Neurons signal to each other and to non-neuronal cells as those in muscle or glands, by means of the secretion of neurotransmitters at chemical synapses. In order to dissect the molecular mechanisms of neurotransmission, new methods for directly and reversibly triggering neurosecretion at the presynaptic terminal are necessary. Here we exploit the calcium permeability of the light-gated channel LiGluR in order to reversibly manipulate cytosolic calcium concentration, thus controlling calcium-regulated exocytosis. METHODS Bovine chromaffin cells expressing LiGluR were stimulated with light. Exocytic events were detected by amperometry or by whole-cell patch-clamp to quantify membrane capacitance and calcium influx. RESULTS Amperometry reveals that optical stimulation consistently triggers exocytosis in chromaffin cells. Secretion of catecholamines can be adjusted between zero and several Hz by changing the wavelength of illumination. Differences in secretion efficacy are found between the activation of LiGluR and native voltage-gated calcium channels (VGCCs). Our results show that the distance between sites of calcium influx and vesicles ready to be released is longer when calcium influx is triggered by LiGluR instead of native VGCCs. CONCLUSION LiGluR activation directly and reversibly increases the intracellular calcium concentration. Light-gated calcium influx allows for the first time to control calcium-regulated exocytosis without the need of applying depolarizing solutions or voltage clamping in chromaffin cells. GENERAL SIGNIFICANCE LiGluR is a useful tool to study the secretory mechanisms and their spatiotemporal patterns in neurotransmission, and opens a window to study other calcium-dependent processes such as muscular contraction or cell migration.
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Affiliation(s)
- Mercè Izquierdo-Serra
- Institute for Bioengineering of Catalonia (IBEC), 15-21 Baldiri Reixac, 08028 Barcelona, Spain
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20
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Yakovleva OV, Shafigullin MU, Sitdikova GF. The role of nitric oxide in the regulation of neurotransmitter release and processes of exo- and endocytosis of synaptic vesicles in mouse motor nerve endings. NEUROCHEM J+ 2013. [DOI: 10.1134/s1819712413020104] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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21
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Galkina SI, Fedorova NV, Stadnichuk VI, Sud'ina GF. Membrane tubulovesicular extensions (cytonemes): secretory and adhesive cellular organelles. Cell Adh Migr 2013; 7:174-86. [PMID: 23287580 DOI: 10.4161/cam.23130] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In this review, we summarized data on the formation and structure of the long and highly adhesive membrane tubulovesicular extensions (TVEs, membrane tethers or cytonemes) observed in human neutrophils and other mammalian cells, protozoan parasites and bacteria. We determined that TVEs are membrane protrusions characterized by a uniform diameter (130-250 nm for eukaryotic cells and 60-90 nm for bacteria) along the entire length, an outstanding length and high rate of development and a high degree of flexibility and capacity for shedding from the cells. This review represents TVEs as protrusions of the cellular secretory process, serving as intercellular adhesive organelles in eukaryotic cells and bacteria. An analysis of the physical and chemical approaches to induce TVEs formation revealed that disrupting the actin cytoskeleton and inhibiting glucose metabolism or vacuolar-type ATPase induces TVE formation in eukaryotic cells. Nitric oxide is represented as a physiological regulator of TVE formation.
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Affiliation(s)
- Svetlana I Galkina
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia.
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22
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Abstract
BACKGROUND Gabapentin is most commonly prescribed for chronic pain, but acute perioperative effects, including preemptive analgesia and hemodynamic stabilization, have been reported. Adrenal chromaffin cells are a widely used model to investigate neurosecretion, and adrenal catecholamines play important physiologic roles and contribute to the acute stress response. However, the effects of gabapentin on adrenal catecholamine release have never been tested. METHODS Primary cultures of bovine adrenal chromaffin cells were treated with gabapentin or vehicle for 18-24 h. The authors quantified catecholamine secretion from dishes of cells using high-performance liquid chromatography and resolved exocytosis of individual secretory vesicles from single cells using carbon fiber amperometry. Voltage-gated calcium channel currents were recorded using patch clamp electrophysiology and intracellular [Ca2+] using fluorescent imaging. RESULTS Gabapentin produced statistically significant reductions in catecholamine secretion evoked by cholinergic agonists (24 ± 3%, n = 12) or KCl (16 ± 4%, n = 8) (mean ± SEM) but did not inhibit Ca2+ entry or calcium channel currents. Amperometry (n = 51 cells) revealed that gabapentin inhibited the number of vesicles released upon stimulation, with no change in quantal size or kinetics of these unitary events. CONCLUSIONS The authors show Ca2+ entry was not inhibited by gabapentin but was less effective at triggering vesicle fusion. The work also demonstrates that chromaffin cells are a useful model for additional investigation of the cellular mechanism(s) by which gabapentin controls neurosecretion. In addition, it identifies altered adrenal catecholamine release as a potential contributor to some of the beneficial perioperative effects of gabapentin.
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Padín JF, de Diego AM, Fernández-Morales JC, Merino C, Maroto M, Calvo-Gallardo E, Arranz JA, Yáñez M, García AG. Resveratrol augments nitric oxide generation and causes store calcium release in chromaffin cells. Eur J Pharmacol 2012; 685:99-107. [DOI: 10.1016/j.ejphar.2012.03.040] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Revised: 03/16/2012] [Accepted: 03/23/2012] [Indexed: 12/29/2022]
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24
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Díaz-Vera J, Camacho M, Machado JD, Domínguez N, Montesinos MS, Hernández-Fernaud JR, Luján R, Borges R. Chromogranins A and B are key proteins in amine accumulation, but the catecholamine secretory pathway is conserved without them. FASEB J 2011; 26:430-8. [PMID: 21990378 DOI: 10.1096/fj.11-181941] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Chromogranins are the main soluble proteins in the large dense core secretory vesicles (LDCVs) found in aminergic neurons and chromaffin cells. We recently demonstrated that chromogranins A and B each regulate the concentration of adrenaline in chromaffin granules and its exocytosis. Here we have further studied the role played by these proteins by generating mice lacking both chromogranins. Surprisingly, these animals are both viable and fertile. Although chromogranins are thought to be essential for their biogenesis, LDCVs were evident in these mice. These vesicles do have a somewhat atypical appearance and larger size. Despite their increased size, single-cell amperometry recordings from chromaffin cells showed that the amine content in these vesicles is reduced by half. These data demonstrate that although chromogranins regulate the amine concentration in LDCVs, they are not completely essential, and other proteins unrelated to neurosecretion, such as fibrinogen, might compensate for their loss to ensure that vesicles are generated and the secretory pathway conserved.
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Affiliation(s)
- Jésica Díaz-Vera
- Unidad de Farmacología, Universidad de La Laguna, La Laguna, Tenerife, Spain
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25
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Milla J, Montesinos MS, Machado JD, Borges R, Alonso E, Moreno-Ortega AJ, Cano-Abad MF, García AG, Ruiz-Nuño A. Ouabain enhances exocytosis through the regulation of calcium handling by the endoplasmic reticulum of chromaffin cells. Cell Calcium 2011; 50:332-42. [PMID: 21741086 DOI: 10.1016/j.ceca.2011.06.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 05/23/2011] [Accepted: 06/09/2011] [Indexed: 11/18/2022]
Abstract
The augmentation of neurotransmitter and hormone release produced by ouabain inhibition of plasmalemmal Na+/K+-ATPase (NKA) is well established. However, the mechanism underlying this action is still controversial. Here we have shown that in bovine adrenal chromaffin cells ouabain diminished the mobility of chromaffin vesicles, an indication of greater number of docked vesicles at subplasmalemmal exocytotic sites. On the other hand, ouabain augmented the number of vesicles undergoing exocytosis in response to a K+ pulse, rather than the quantal size of single vesicles. Furthermore, ouabain produced a tiny and slow Ca2+ release from the endoplasmic reticulum (ER) and gradually augmented the transient elevations of the cytosolic Ca2+ concentrations ([Ca2+]c) triggered by K+ pulses. These effects were paralleled by gradual increments of the transient catecholamine release responses triggered by sequential K+ pulses applied to chromaffin cell populations treated with ouabain. Both, the increases of K+-elicited [Ca2+]c and secretion in ouabain-treated cells were blocked by thapsigargin (THAPSI), 2-aminoethoxydiphenyl borate (2-APB) and caffeine. These results are compatible with the view that ouabain may enhance the ER Ca2+ load and facilitate the Ca2+-induced-Ca2+ release (CICR) component of the [Ca2+]c signal generated during K+ depolarisation. This could explain the potentiating effects of ouabain on exocytosis.
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Affiliation(s)
- Juan Milla
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de Madrid, and Servicio de Farmacología Clínica, Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa, Madrid, Spain
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26
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Borges R, Pereda D, Beltrán B, Prunell M, Rodríguez M, Machado JD. Intravesicular factors controlling exocytosis in chromaffin cells. Cell Mol Neurobiol 2010; 30:1359-64. [PMID: 21046452 DOI: 10.1007/s10571-010-9589-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Accepted: 09/02/2010] [Indexed: 11/29/2022]
Abstract
Chromaffin granules are similar organelles to the large dense core vesicles (LDCV) present in many secretory cell types including neurons. LDCV accumulate solutes at high concentrations (catecholamines, 0.5-1 M; ATP, 120-300 mM; or Ca(2+), 40 mM (Bulenda and Gratzl Biochemistry 24:7760-7765, 1985). Solutes seem to aggregate to a condensed matrix to elude osmotic lysis. The affinity of solutes for LDCV matrix is responsible for the delayed release of catecholamines during exocytosis. The aggregation of solutes occurs due to a specific H(+) pump denominated V-ATPase that maintains an inner acidic media (pH ≈5.5). This pH gradient against cytosol is also responsible for the vesicular accumulation of amines and Ca(2+). When this gradient is reduced by modulation of the V-ATPase activity, catecholamines and Ca(2+) are moved toward the cytosol. In addition, some drugs largely accumulate inside LDCV and not only impair the accumulation of natural solutes, but also act as false neurotransmitters when they are co-released with catecholamines. There is much experimental evidence to conclude that the physiological modulation of vesicle pH and the manipulation of intravesicular media with drugs affect the LDCV cargo and change the kinetics of exocytosis. Here, we will present some experimental data demonstrating the participation of drugs in the kinetics of exocytosis through changes in the composition of vesicular media. We also offer a model to explain the regulation of exocytosis by the intravesicular media that conciliate the experimentally obtained data.
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Affiliation(s)
- Ricardo Borges
- Unit of Pharmacology, Medical School, La Laguna University, 38071 La Laguna, Tenerife, Spain.
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27
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Fernández-Morales JC, Yáñez M, Orallo F, Cortés L, González JC, Hernández-Guijo JM, García AG, de Diego AMG. Blockade by nanomolar resveratrol of quantal catecholamine release in chromaffin cells. Mol Pharmacol 2010; 78:734-44. [PMID: 20631052 DOI: 10.1124/mol.110.066423] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The cardiovascular protecting effects of resveratrol, an antioxidant polyphenol present in grapes and wine, have been attributed to its vasorelaxing effects and to its anti-inflammatory, antioxidant, and antiplatelet actions. Inhibition of adrenal catecholamine release has also been recently implicated in its cardioprotecting effects. Here, we have studied the effects of nanomolar concentrations of resveratrol on quantal single-vesicle catecholamine release in isolated bovine adrenal chromaffin cells. We have found that 30 to 300 nM concentrations of resveratrol blocked the acetylcholine (ACh) and high K(+)-evoked quantal catecholamine release, amperometrically measured with a carbon fiber microelectrode. At these concentrations, resveratrol did not affect the whole-cell inward currents through nicotinic receptors or voltage-dependent sodium and calcium channels, neither the ACh- or K(+)-elicited transients of cytosolic Ca(2+). Blockade by nanomolar resveratrol of secretion in ionomycin- or digitonin-treated cells suggests an intracellular site of action beyond Ca(2+)-dependent exocytotic steps. The fact that nanomolar resveratrol augmented cGMP is consistent with the view that resveratrol could be blocking the quantal secretion of catecholamine through a nitric oxide-linked mechanism. Because this effect occurs at nanomolar concentrations, our data are relevant in the context of the low circulating levels of resveratrol found in moderate consumers of red wines, which could afford cardioprotection by mitigating the catecholamine surge occurring during stress.
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Borges R, Díaz-Vera J, Domínguez N, Arnau MR, Machado JD. Chromogranins as regulators of exocytosis. J Neurochem 2010; 114:335-43. [PMID: 20456013 DOI: 10.1111/j.1471-4159.2010.06786.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Chromogranins (Cgs) constitute the main protein component in the vesicular matrix of large dense core vesicles (LDCV). These acidic proteins have been implicated in several physiological processes such as vesicle sorting, the generation of bioactive peptides and the accumulation of soluble species inside LDCV. This latter feature of Cgs accounts for the ability of vesicles to concentrate catecholamines and Ca(2+). Indeed, the low affinity and high capacity of Cgs to bind solutes at the low pH of the LDCV lumen seems to be behind the delay in the neurotransmitter exit towards the extracellular milieu after vesicle fusion. The availability of new mouse strains lacking Cgs in combination with the arrival of several techniques for the direct monitoring of exocytosis (like amperometry, patch-amperometry and intracellular electrochemistry), have helped advance our understanding of how these granins concentrate catecholamines and Ca(2+) in LDCV, and how they influence the kinetics of exocytosis. In this review, we will discuss the roles of Cgs A and B in maintaining the intravesicular environment of secretory vesicles and in exocytosis, bringing together the most recent findings from adrenal chromaffin cells.
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Affiliation(s)
- Ricardo Borges
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, Tenerife, Spain.
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29
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Montesinos MS, Camacho M, Machado JD, Viveros OH, Beltrán B, Borges R. The quantal secretion of catecholamines is impaired by the accumulation of beta-adrenoceptor antagonists into chromaffin cell vesicles. Br J Pharmacol 2010; 159:1548-56. [PMID: 20233226 DOI: 10.1111/j.1476-5381.2010.00650.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND AND PURPOSE The delayed onset of certain effects of antagonists of beta-adrenoceptors (beta-blockers), such as lowering arterial blood pressure (several days), cannot be explained solely by their effects on beta-adrenoceptors, an action that occurs within minutes. Although several mechanisms have been proposed, none of them explain this temporal delay. This work aimed at providing a new explanation based on the interference of these drugs with the functional accumulation of catecholamines within neurosecretory vesicles. EXPERIMENTAL APPROACH We used the simultaneous on-line monitoring of catecholamine and labetalol release from bovine isolated chromaffin cells and from rat perfused adrenal glands, as well as single cell amperometry, intracellular electrochemistry, patch amperometry and HPLC. KEY RESULTS Using amperometry, three beta-blockers, labetalol, atenolol and propranolol, reduced the quantal size of secretory events in chromaffin cells, accompanied by a slowing down of exocytosis. By patch amperometry, we found that treatment with beta-blockers also increases the chromaffin vesicle volume, thereby creating a functional dilution of catecholamines. Experiments with intracellular electrochemistry show that vesicles cannot uptake new catecholamines. There was progressive accumulation of labetalol in secretory vesicles of bovine adrenal chromaffin cells, and this beta-blocker was co-released with catecholamines from rat and bovine chromaffin tissues. CONCLUSIONS AND IMPLICATIONS We propose that beta-blockers are progressively concentrated into sympathetic secretory vesicles, and interfere with the storage of catecholamines and are co-released with the natural transmitters, resulting in a decrease in the sympathetic tone. This could explain the delayed onset of the hypotensive effects of beta-blockers.
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Affiliation(s)
- Mónica S Montesinos
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, Tenerife, Spain
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Chromogranin B gene ablation reduces the catecholamine cargo and decelerates exocytosis in chromaffin secretory vesicles. J Neurosci 2010; 30:950-7. [PMID: 20089903 DOI: 10.1523/jneurosci.2894-09.2010] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Chromogranins/secretogranins (Cgs) are the major soluble proteins of large dense-core secretory vesicles (LDCVs). We have recently reported that the absence of chromogranin A (CgA) caused important changes in the accumulation and in the exocytosis of catecholamines (CAs) using a CgA-knock-out (CgA-KO) mouse. Here, we have analyzed a CgB-KO mouse strain that can be maintained in homozygosis. These mice have 36% less adrenomedullary epinephrine when compared to Chgb(+/+) [wild type (WT)], whereas the norepinephrine content was similar. The total evoked release of CA was 33% lower than WT mice. This decrease was not due to a lower frequency of exocytotic events but to less secretion per quantum (approximately 30%) measured by amperometry; amperometric spikes exhibited a slower ascending but a normal decaying phase. Cell incubation with L-DOPA increased the vesicle CA content of WT but not of the CgB-KO cells. Intracellular electrochemistry, using patch amperometry, showed that L-DOPA overload produced a significantly larger increase in cytosolic CAs in cells from the KO animals than chromaffin cells from the WT. These data indicate that the mechanisms for vesicular accumulation of CAs in the CgB-KO cells were saturated, while there was ample capacity for further accumulation in WT cells. Protein analysis of LDCVs showed the overexpression of CgA as well as other proteins apparently unrelated to the secretory process. We conclude that CgB, like CgA, is a highly efficient system directly involved in monoamine accumulation and in the kinetics of exocytosis from LDCVs.
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31
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Galkina SI, Romanova JM, Stadnichuk VI, Molotkovsky JG, Sud'ina GF, Klein T. Nitric oxide-induced membrane tubulovesicular extensions (cytonemes) of human neutrophils catch and holdSalmonella entericaserovar Typhimurium at a distance from the cell surface. ACTA ACUST UNITED AC 2009; 56:162-71. [DOI: 10.1111/j.1574-695x.2009.00560.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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S-nitrosylation of syntaxin 1 at Cys(145) is a regulatory switch controlling Munc18-1 binding. Biochem J 2008; 413:479-91. [PMID: 18452404 DOI: 10.1042/bj20080069] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Exocytosis is regulated by NO in many cell types, including neurons. In the present study we show that syntaxin 1a is a substrate for S-nitrosylation and that NO disrupts the binding of Munc18-1 to the closed conformation of syntaxin 1a in vitro. In contrast, NO does not inhibit SNARE {SNAP [soluble NSF (N-ethylmaleimide-sensitive fusion protein) attachment protein] receptor} complex formation or binding of Munc18-1 to the SNARE complex. Cys(145) of syntaxin 1a is the target of NO, as a non-nitrosylatable C145S mutant is resistant to NO and novel nitrosomimetic Cys(145) mutants mimic the effect of NO on Munc18-1 binding in vitro. Furthermore, expression of nitrosomimetic syntaxin 1a in living cells affects Munc18-1 localization and alters exocytosis release kinetics and quantal size. Molecular dynamic simulations suggest that NO regulates the syntaxin-Munc18 interaction by local rearrangement of the syntaxin linker and H3c regions. Thus S-nitrosylation of Cys(145) may be a molecular switch to disrupt Munc18-1 binding to the closed conformation of syntaxin 1a, thereby facilitating its engagement with the membrane fusion machinery.
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Amatore C, Arbault S, Guille M, Lemaître F. Electrochemical Monitoring of Single Cell Secretion: Vesicular Exocytosis and Oxidative Stress. Chem Rev 2008; 108:2585-621. [DOI: 10.1021/cr068062g] [Citation(s) in RCA: 316] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Semple JW, Speck ER, Fabron A, Kim RAM, Freedman J. A novel immunosuppressive pathway involving peroxynitrite-mediated [corrected] nitration of platelet antigens within antigen-presenting cells. Transfusion 2008; 48:1917-24. [PMID: 18564400 DOI: 10.1111/j.1537-2995.2008.01793.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Studies have demonstrated that immunity against platelet (PLT) transfusions is dependent on recipient antigen-presenting cells (APCs) and their ability to produce nitric oxide (NO). To further analyze this, we focused on NO's major metabolite peroxynitrite (ONOO(-)) and its ability to affect PLT immunity. STUDY DESIGN AND METHODS To address how NO and its major metabolite may mediate PLT immunity, GP91(PHOX) knockout (KO) mice that lack the ability to produce the ONOO(-) were transfused weekly with allogeneic BALB/c PLTs, and donor antibody development was analyzed. RESULTS Compared with controls, GP91(PHOX) KO mice developed significantly (p < 0.0001) higher-titered immunoglobulin G (IgG) donor antibodies by two transfusions, and this immune response could be inhibited by treating the recipient mice with aminoguanidine, a relatively selective inhibitor of inducible nitric oxide synthase. In vitro nitration of PLTs did not alter PLT antibody binding but significantly inhibited the transfused PLT's ability to stimulate IgG immunity in either wild-type or KO mice. The lack of nitrated PLT immunity correlated with an inability of APCs to mediate phagocytosis of nitrated PLTs. The lack of nitrated PLT immunity could only be restored when normal PLTs were mixed with the nitrated PLTs and transfused. CONCLUSION The results identify a dual role for NO metabolism within APCs that significantly modulates PLT immunity; nitration of PLT antigens leads to lack of immunity due to an inability of APCs to move PLT antigens intracellularly whereas there exists an NO-dependent pathway that stimulates anti-PLT immunity.
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Affiliation(s)
- John W Semple
- Keenan Research Centre, Li Ka Shing Knowledge Institute, St Michael's Hospital, Toronto, Ontario, Canada.
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Camacho M, Machado JD, Alvarez J, Borges R. Intravesicular calcium release mediates the motion and exocytosis of secretory organelles: a study with adrenal chromaffin cells. J Biol Chem 2008; 283:22383-9. [PMID: 18562320 DOI: 10.1074/jbc.m800552200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Secretory vesicles of sympathetic neurons and chromaffin granules maintain a pH gradient toward the cytosol (pH 5.5 versus 7.2) promoted by the V-ATPase activity. This gradient of pH is also responsible for the accumulation of amines and Ca2+ because their transporters use H+ as the counter ion. We have recently shown that alkalinization of secretory vesicles slowed down exocytosis, whereas acidification caused the opposite effect. In this paper, we measure the alkalinization of vesicular pH, caused by the V-ATPase inhibitor bafilomycin A1, by total internal reflection fluorescence microscopy in cells overexpressing the enhanced green fluorescent protein-labeled synaptobrevin (VAMP2-EGFP) protein. The disruption of the vesicular gradient of pH caused the leak of Ca2+, measured with fura-2. Fluorimetric measurements, using the dye Oregon green BAPTA-2, showed that bafilomycin directly released Ca2+ from freshly isolated vesicles. The Ca2+ released from vesicles to the cytosol dramatically increased the granule motion of chromaffin- or PC12-derived granules and triggered exocytosis (measured by amperometry). We conclude that the gradient of pH of secretory vesicles might be involved in the homeostatic regulation of cytosolic Ca2+ and in two of the major functions of secretory cells, vesicle motion and exocytosis.
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Affiliation(s)
- Marcial Camacho
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna Tenerife, E-38071 La Laguna, Spain
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The crucial role of chromogranins in storage and exocytosis revealed using chromaffin cells from chromogranin A null mouse. J Neurosci 2008; 28:3350-8. [PMID: 18367602 DOI: 10.1523/jneurosci.5292-07.2008] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Chromogranins (Cgs) are the major soluble proteins of dense-core secretory vesicles. Chromaffin cells from Chga null mice [chromogranin A knock-out (CgA-KO)] exhibited approximately 30% reduction in the content and in the release of catecholamines compared with wild type. This was because of a lower secretion per single exocytotic event, rather than to a lower frequency of exocytotic events. Cell incubation with L-DOPA produced an increase in the vesicular amine content of wild-type, but not CgA-KO vesicles. In contrast, intracellular electrochemistry showed that L-DOPA produced a significantly larger increase in cytosolic amines in CgA-KO cells than in the wild type. These data indicate that the mechanisms for vesicular accumulation in CgA-KO cells were fully saturated. Patch-amperometry recordings showed a delayed initiation of the amperometric signal after vesicle fusion, whereas no changes were observed in vesicle size or fusion pore kinetics despite the smaller amine content. We conclude that intravesicular proteins are highly efficient systems directly implicated in transmitter accumulation and in the control of neurosecretion.
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Borges R, Camacho M, Gillis KD. Measuring secretion in chromaffin cells using electrophysiological and electrochemical methods. Acta Physiol (Oxf) 2008; 192:173-84. [PMID: 18021323 DOI: 10.1111/j.1748-1716.2007.01814.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Our present understanding of exocytosis of catecholamines has benefited tremendously from the arrival of single-cell electrochemical methods (amperometry and voltammetry), electrophysiological techniques (whole-cell and patch capacitance) and from the combination of both techniques (patch amperometry). In this brief review, we will outline the strengths and limitations of amperometric and electrophysiological methods and highlight the major contribution obtained with the use of these techniques in chromaffin cells.
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Affiliation(s)
- R Borges
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, Tenerife, Spain.
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38
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Ida T, Hara M, Nakamura Y, Kozaki S, Tsunoda S, Ihara H. Cytokine-induced enhancement of calcium-dependent glutamate release from astrocytes mediated by nitric oxide. Neurosci Lett 2007; 432:232-6. [PMID: 18255223 DOI: 10.1016/j.neulet.2007.12.047] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2007] [Revised: 11/17/2007] [Accepted: 12/13/2007] [Indexed: 01/09/2023]
Abstract
Cytokines are produced in the central nervous system (CNS) and exhibit various effects on neurons, microglia, and astrocytes. Astrocytes can release chemical transmitters, including glutamate, in a calcium-dependent manner, which may mediate communication between neurons and astrocytes. To date, no studies have been conducted on the effects of cytokines on calcium-dependent glutamate release from astrocytes. Here, we studied the effects of cytokines on calcium-dependent glutamate release. Cytokines enhanced glutamate release and induced the expression of inducible nitric oxide synthase (iNOS) and the production of nitric oxide (NO). The inhibition of iNOS eliminated the cytokine-induced enhancement of glutamate release, and treatment with a NO donor, even in the absence of cytokines, increased glutamate release. Thus, cytokines enhance glutamate release, and this enhancement is mediated by NO.
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Affiliation(s)
- Tomoaki Ida
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, Japan
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Tsutsuki H, Kohda T, Hara M, Kozaki S, Ihara H. Nitric oxide inhibits depolarization-evoked glutamate release from rat cerebellar granule cells. Nitric Oxide 2007; 16:217-27. [PMID: 17126044 DOI: 10.1016/j.niox.2006.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Revised: 10/01/2006] [Accepted: 10/06/2006] [Indexed: 10/24/2022]
Abstract
Nitric oxide (NO) modulates the release of various neurotransmitters, some of these are considered to be involved in neuronal plasticity that includes long-term depression in the cerebellum. To date, there have been no reports on the modulation of the exocytotic release of neurotransmitters in the cerebellar granule cells (CGCs) by NO. The aim of this study was to investigate the effects of NO on the exocytotic release of glutamate from rat CGCs. Treatment with NO-related reagents revealed that NO inhibited high-K(+)-evoked glutamate release. Clostridium botulinum type B neurotoxin (BoNT/B) attenuated the enhancement of glutamate release caused by NO synthase (NOS) inhibition; this indicates that NO acts on the high-K(+)-evoked exocytotic pathway. cGMP-related reagents did not affect the high-K(+)-evoked glutamate release. NO-related reagents did not affect Ca(2+) ionophore-induced glutamate release, suggesting that NO inhibits Ca(2+) entry through voltage-dependent Ca(2+) channels (VDCC). Monitoring of intracellular Ca(2+) revealed that NO inhibited high-K(+)-evoked Ca(2+) entry. L-type VDCC blockers inhibited glutamate release and NO did not have an additive effect on the inhibition produced by the L-type VDCC blocker. The inhibition of the high-K(+)-evoked glutamate release by NO was abolished by a reducing reagent; this suggested that NO regulates the high-K(+)-evoked glutamate release from CGCs by redox modulation.
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Affiliation(s)
- Hiroyasu Tsutsuki
- Department of Biological Science, Graduate School of Science, Osaka Prefecture University, Gakuen-cho, Sakai, Osaka, Japan
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Ardiles AO, Maripillán J, Lagos VL, Toro R, Mora IG, Villarroel L, Alés E, Borges R, Cárdenas AM. A rapid exocytosis mode in chromaffin cells with a neuronal phenotype. J Neurochem 2006; 99:29-41. [PMID: 16889641 DOI: 10.1111/j.1471-4159.2006.04080.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We have used astrocyte-conditioned medium (ACM) to promote the transdifferentiation of bovine chromaffin cells and study modifications in the exocytotic process when these cells acquire a neuronal phenotype. In the ACM-promoted neuronal phenotype, secretory vesicles and intracellular Ca2+ rise were preferentially distributed in the neurite terminals. Using amperometry, we observed that the exocytotic events also occurred mainly in the neurite terminals, wherein the individual exocytotic events had smaller quantal size than in undifferentiated cells. Additionally, duration of pre-spike current was significantly shorter, suggesting that ACM also modifies the fusion pore stability. After long exposure (7-9 days) to ACM, the kinetics of catecholamine release from individual vesicles was markedly accelerated. The morphometric analysis of vesicle diameters suggests that the rapid exocytotic events observed in neurites of ACM-treated cells correspond to the exocytosis of large dense-core vesicles (LDCV). On the other hand, experiments performed in EGTA-loaded cells suggest that ACM treatment promotes a better coupling between voltage-gated calcium channels (VGCC) and LDCV. Thus, our findings reveal that ACM promotes a neuronal phenotype in chromaffin cells, wherein the exocytotic kinetics is accelerated. Such rapid exocytosis mode could be caused at least in part by a better coupling between secretory vesicles and VGCC.
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Affiliation(s)
- Alvaro O Ardiles
- Centro de Neurociencia de Valparaíso, Universidad de Valparaíso, Chile
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41
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Saad AH, Shimamoto C, Nakahari T, Fujiwara S, Katsu KI, Marunaka Y. cGMP modulation of ACh-stimulated exocytosis in guinea pig antral mucous cells. Am J Physiol Gastrointest Liver Physiol 2006; 290:G1138-48. [PMID: 16423923 DOI: 10.1152/ajpgi.00357.2005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In guinea pig antral mucous cells, ACh stimulates the Ca(2+)-regulated exocytosis, which has a characteristics feature: an initial transient phase followed by a sustained phase. The effects of cGMP on ACh-stimulated exocytosis were studied in guinea pig antral mucous cells using video microscopy. cGMP enhanced the frequency of ACh-stimulated exocytotic events, whereas cGMP alone did not induce any exocytotic events under the ACh-unstimulated condition. cGMP did not stimulate either Ca(2+) mobilization or cAMP accumulation. The Ca(2+) dose-response studies demonstrated that cGMP shifted the dose-response curve upward with no shift to the lower concentration. This indicates that cGMP increased maximal responsiveness of the Ca(2+)-regulated exocytosis, but not the Ca(2+) sensitivity. Moreover, under a condition of ATP depletion by dinitrophenol (DNP) or anoxia (N(2) bubbling), ACh evoked only a sustained phase in exocytotic events with no initial transient phase. However, ACh evoked an initial transient phase followed by a sustained phase with addition of cGMP before ATP depletion, whereas only a sustained phase was evoked in a case of cGMP addition after ATP depletion. Thus cGMP-induced enhancement in ACh-stimulated exocytotic events requires ATP, suggesting that cGMP modulates ATP-dependent priming of Ca(2+)-regulated exocytosis in antral mucous cells. In conclusion, cGMP increases the number of primed granules via acceleration of the ATP-dependent priming, which enhances the Ca(2+)-regulated exocytosis stimulated by ACh.
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Affiliation(s)
- Adel H Saad
- Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Japan
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42
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Camacho M, Machado JD, Montesinos MS, Criado M, Borges R. Intragranular pH rapidly modulates exocytosis in adrenal chromaffin cells. J Neurochem 2005; 96:324-34. [PMID: 16336635 DOI: 10.1111/j.1471-4159.2005.03526.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Several drugs produce rapid changes in the kinetics of exocytosis of catecholamines, as measured at the single event level with amperometry. This study is intended to unveil whether the mechanism(s) responsible for these effects involve changes in the intravesicular pH. Cell incubation with bafilomycin A1, a blocker of the vesicular proton pump, caused both a deceleration in the kinetics of exocytosis and a reduction in the catecholamine content of vesicle. These effects were also observed upon reduction of proton gradient by nigericin or NH4Cl. pH measurements using fluorescent probes (acridine orange, quinacrine or enhanced green fluorescent protein-synaptobrevin) showed a strong correlation between vesicular pH and the kinetics of exocytosis. Hence, all maneuvers tested that decelerated exocytosis also alkalinized secretory vesicles and vice versa. On the other hand, calcium entry caused a transient acidification of granules. We therefore propose that the regulation of vesicular pH is, at least partially, a necessary step in the modulation of the kinetics of exocytosis and quantal size operated by some cell signals.
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Affiliation(s)
- Marcial Camacho
- Unidad de Farmacología, Facultad de Medicina, Universidad de La Laguna, Tenerife, Spain
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43
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Fernández-Peruchena C, Navas S, Montes MA, Alvarez de Toledo G. Fusion pore regulation of transmitter release. ACTA ACUST UNITED AC 2005; 49:406-15. [PMID: 16111567 DOI: 10.1016/j.brainresrev.2004.12.037] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2004] [Revised: 12/13/2004] [Accepted: 12/29/2004] [Indexed: 11/28/2022]
Abstract
During the last decade a wealth of new information about the properties of the exocytotic fusion pore is changing our current view of exocytosis. The exocytotic fusion pore, a necessary stage before the full merging of the vesicle membrane with the plasma membrane, is becoming a key cellular structure that might critically control the amount of neurotransmitter released into the synaptic cleft and that can be subjected to control by second messengers and phosphorylated proteins. Fusion pores form, expand to fully merge membranes, or can close leaving an intact and identical synaptic vesicle in place for a new round of exocytosis. Transient formation of fusion pores is the mechanistic representation of the "kiss-and-run" hypothesis of transmitter release and offers new alternatives for synaptic vesicle recycling besides to the classical mechanism mediated by clathrin coat endocytosis. For vesicle recycling transient fusion pores ensures a fast mechanism for maintaining an active pool of synaptic vesicles. The size reached by transient fusion pores and the time spent on the open state can determine the release of subquantal synaptic transmission, which could be a mechanism of synaptic potentiation. In this review we will described the electrophysiological and fluorescence methods that contribute to further explore the biophysical properties of the exocytotic fusion pore and the relevant experiments obtained by these methods.
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Affiliation(s)
- Carlos Fernández-Peruchena
- Departamento de Fisiología Médica y Biofísica, Facultad de Medicina, Universidad de Sevilla, Avda. Sánchez Pizjuán 4, 41009 Sevilla, Spain
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Xu J, Tang KS, Lu VB, Weerasinghe CP, Tse A, Tse FW. Maintenance of quantal size and immediately releasable granules in rat chromaffin cells by glucocorticoid. Am J Physiol Cell Physiol 2005; 289:C1122-33. [PMID: 15930142 DOI: 10.1152/ajpcell.00514.2004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Glucocorticoid is reported to regulate catecholamine synthesis and storage. However, it is not clear whether the actual amount of catecholamine released from individual granules (quantal size, Q) in mature chromaffin cells is affected by glucocorticoid. Using carbon fiber amperometry, we found that dexamethasone did not affect mean cellular Q or the proportional release from different populations of granules in rat chromaffin cells cultured for 1 day in a serum-free defined medium. After two extra days of culture in the defined medium, there was a rundown in mean cellular Q, and it was associated with a shift in the proportional release from the different granule populations. This phenomenon could not be rescued by serum supplementation but could be prevented by dexamethasone via an action that was independent of changes in voltage-gated Ca(2+) channel (VGCC) density. Using simultaneous measurements of membrane capacitance and cytosolic Ca(2+) concentration, we found that for cells cultured in defined medium dexamethasone enhanced the exocytotic response triggered by a brief depolarization (50 ms) without affecting the VGCC density or the fast exocytotic response triggered via flash photolysis of caged Ca(2+). Thus glucocorticoid may regulate the number of immediately releasable granules that are in close proximity to a subset of VGCC. Because chromaffin cells in vivo are exposed to high concentrations of glucocorticoid, our findings suggest that the paracrine actions of glucocorticoid maintain the mean catecholamine content in chromaffin cell granules as well as the colocalization of releasable granules with VGCCs.
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Affiliation(s)
- Jianhua Xu
- Department of Pharmacology, 9-70 Medical Sciences Bldg., University of Alberta, Edmonton, AB T6G 2H7, Canada
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Vicente S, Figueroa S, Pérez-Rodríguez R, González MP, Oset-Gasque MJ. Nitric oxide donors induce calcium-mobilisation from internal stores but do not stimulate catecholamine secretion by bovine chromaffin cells in resting conditions. Cell Calcium 2005; 37:163-72. [PMID: 15589996 DOI: 10.1016/j.ceca.2004.09.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2003] [Revised: 06/08/2004] [Accepted: 09/21/2004] [Indexed: 11/17/2022]
Abstract
The potential role of nitric oxide (NO) donors and peroxynitrites on both basal catecholamine (CA) secretion and modulation of calcium levels has been investigated in primary cultures of bovine chromaffin cells. NO donors did not modulate catecholamine secretion, while peroxynitrites induced a time dose-dependent increase in basal CA secretion. Two facts may explain the lack of these compounds on basal CA secretion. NO donors induce, on the one hand, an increase in intracellular calcium levels by depletion of internal IP3-stores from endoplasmic reticulum. On the other hand, a small calcium influx through N-type voltage-dependent calcium channels (VDCC), which seem not to be coupled to exocytosis of adrenaline and noradrenaline in chromaffin cells. Both effects, calcium-mobilisation from internal stores and calcium entry through N-type VDCC are mediated by cGMP synthesis. In contrast, peroxynitrites induce an increase in basal CA secretion by both a decrease of intracellular catecholamine content and a toxic effect on cellular membrane. All these results, taken together, could explain contradictory results in the literature on the role of NO on basal catecholamine secretion and on modulation of intracellular calcium in chromaffin cells.
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Affiliation(s)
- S Vicente
- Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, Complutense University of Madrid, E-28040 Madrid, Spain
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Mohn CE, Fernandez-Solari J, De Laurentiis A, Prestifilippo JP, de la Cal C, Funk R, Bornstein SR, McCann SM, Rettori V. The rapid release of corticosterone from the adrenal induced by ACTH is mediated by nitric oxide acting by prostaglandin E2. Proc Natl Acad Sci U S A 2005; 102:6213-8. [PMID: 15837925 PMCID: PMC1087960 DOI: 10.1073/pnas.0502136102] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The adrenal cortex is a major stress organ in mammals that reacts rapidly to a multitude of external and internal stressors. Adrenocorticotropin (ACTH) is the main stimulator of the adrenal cortex, activating corticosteroid synthesis and secretion. We evaluated the mechanism of action of ACTH on adrenals of male rats, preserving the architecture of the gland in vitro. We demonstrated that both sodium nitroprusside (NP), a nitric oxide (NO) donor, and ACTH stimulate corticosterone release. NO mediated the acute response to ACTH because Nomega-nitro-l-arginine methyl ester, a NO synthase inhibitor, and hemoglobin, a NO scavenger, blocked the stimulation of corticosterone release induced by ACTH. NP stimulated prostaglandin E release, which in turn stimulated corticosterone release from the adrenal. Additionally, indomethacin, which inhibits cyclooxygenase, and thereby, prostaglandin release, prevented corticosterone release from the adrenal induced by both NP and ACTH, demonstrating that prostaglandins mediate acute corticosterone release. Corticosterone content in adrenals after incubation with ACTH or NP was lower than in control glands, indicating that any de novo synthesis of corticosterone during this period was not sufficient to keep up with the release of the stored hormone. The release induced by ACTH or NP depleted the corticosterone content in the adrenal by approximately 40% compared with the content of glands incubated in buffer. The mechanism of rapid release is as follows: NO produced by NO synthase activation by ACTH activates cyclooxygenase, which generates PGE(2), which in turn releases corticosterone stored in microvesicles and other organelles.
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Affiliation(s)
- Claudia E Mohn
- Centro de Estudios Farmacológicos y Botánicos, Consejo Nacional de Investigaciones Científicas y Técnicas, Serrano 669, 1414 Buenos Aires, Argentina
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47
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Galkina SI, Molotkovsky JG, Ullrich V, Sud'ina GF. Scanning electron microscopy study of neutrophil membrane tubulovesicular extensions (cytonemes) and their role in anchoring, aggregation and phagocytosis. The effect of nitric oxide. Exp Cell Res 2005; 304:620-9. [PMID: 15748905 DOI: 10.1016/j.yexcr.2004.12.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2004] [Revised: 12/08/2004] [Accepted: 12/09/2004] [Indexed: 11/24/2022]
Abstract
We have shown that human neutrophils develop dynamic thin and very long tubulovesicular extensions (cytonemes) upon adhesion to fibronectin, if cell spreading was blocked by Na(+)-free medium or by 4-bromophenacyl bromide, N-ethylmaleimide, 7-chloro-4-nitrobenz-2-oxa-1,3-diazole and cytochalasin D (S. I. Galkina, G. F. Sud'ina and V. Ullrich, (2001). Exp. Cell Res. 266, 222-228). In the present work we found that similar in size and behavior tubulovesicular extensions were formed on the neutrophil cell bodies upon adhesion to fibronectin-coated substrata in the presence of the nitric oxide donor diethylamine NONOate. In the presence of the nitric oxide synthase inhibitor N-omega-nitro-L-arginine methyl ester, neutrophils were well spread and had no microextensions. Using scanning electron microscopy, we demonstrated that tubulovesicular extensions of neutrophils executed long-range adhesion and binding objects for phagocytosis, such as serum-opsonized zymosan particles and erythrocytes. Tubulovesicular extensions anchored neutrophils to substrata in a beta1 and beta2 integrin-independent, but L-selectin-dependent manner. BODIPY-sphingomyelin impaired development of tubulovesicular extension, and heparitinase 1 played a role in their destruction. Membrane tubulovesicular extensions are supposed to represent protrusions of an intracellular exocytotic traffic and serve as cellular sensory and adhesive organelles. Nitric oxide seems to play a role in regulation of tubulovesicular extensions formation, thus affecting neutrophil adhesive interactions and phagocytosis.
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Affiliation(s)
- Svetlana I Galkina
- A. N. Belozersky Institute of Physico-Chemical Biology of the M. V. Lomonosov Moscow State University, 119992, Moscow, Leninskie gory, Building A, Moscow, Russia.
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Mahapatra NR, Mahata M, Hazra PP, McDonough PM, O'Connor DT, Mahata SK. A dynamic pool of calcium in catecholamine storage vesicles. Exploration in living cells by a novel vesicle-targeted chromogranin A-aequorin chimeric photoprotein. J Biol Chem 2004; 279:51107-21. [PMID: 15358782 DOI: 10.1074/jbc.m408742200] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Chromaffin vesicles contain very high concentration of Ca2+ (approximately 20-40 mM total), compared with approximately 100 nM in the cytosol. Aequorin, a jellyfish photoprotein with Ca(2+)-dependent luminescence, measures [Ca2+] in specific subcellular compartments wherein proteins with organelle-specific trafficking domains are fused in-frame to aequorin. Because of the presence of vesicular trafficking domain within CgA we engineered sorting of an expressed human CgA-Aequorin fusion protein (hCgA-Aeq) into the vesicle compartment as confirmed by sucrose density gradients and confocal immunofluorescent co-localization studies. hCgA-Aeq and cytoplasmic aequorin (Cyto-Aeq) luminescence displayed linear functions of [Ca2+] in vitro, over >5 log10 orders of magnitude (r > 0.99), and down to at least 10(-7) M sensitivity. Calibrating the pH dependence of hCgA-Aeq luminescence allowed estimation of [Ca2+]ves at granule interior pH (approximately 5.5). In the cytoplasm, Cyto-Aeq accurately determined [Ca2+]cyto under both basal ([Ca2+]cyto = 130 +/- 35 nM) and exocytosis-stimulated conditions, confirmed by an independent reference technique (Indo-1 fluorescence). The hCgA-Aeq chimera determined vesicular free [Ca2+]ves = 1.4 +/- 0.3 microM under basal conditions indicating that >99% of granule total Ca2+ is in a "bound" state. The basal free [Ca2+]ves/[Ca2+]cyto ratio was thus approximately 10.8-fold, indicating active, dynamic Ca2+ uptake from cytosol into the granules. Stimulation of exocytotic secretion revealed prompt, dynamic increases in both [Ca2+](ves) and [Ca2+]cyto, and an exponential relation between the two (y = 0.99 x e(1.53x), r = 0.99), reflecting a persistent [Ca2+]ves/[Ca2+]cyto gradient, even during sharp increments of both values. Studies with inhibitors of Ca2+ translocation (Ca(2+)-ATPase), Na+/Ca(+)-exchange, Na+/H(+)-exchange, and vesicle acidification (H(+)-translocating ATPase), documented a role for these four ion transporter classes in accumulation of Ca2+ inside the vesicles.
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Affiliation(s)
- Nitish R Mahapatra
- Department of Medicine, University of California, San Diego, La Jolla 92093-0838, USA
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Axmacher N, Stemmler M, Engel D, Draguhn A, Ritz R. Transmitter Metabolism as a Mechanism of Synaptic Plasticity: A Modeling Study. J Neurophysiol 2004; 91:25-39. [PMID: 13679396 DOI: 10.1152/jn.00797.2003] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The nervous system adapts to experience by changes in synaptic strength. The mechanisms of synaptic plasticity include changes in the probability of transmitter release and in postsynaptic responsiveness. Experimental and neuropharmacological evidence points toward a third variable in synaptic efficacy: changes in presynaptic transmitter concentration. Several groups, including our own, have reported changes in the amplitude and frequency of postsynaptic (miniature) events indicating that alterations in transmitter content cause alterations in vesicular transmitter content and vesicle dynamics. It is, however, not a priori clear how transmitter metabolism will affect vesicular transmitter content and how this in turn will affect pre- and postsynaptic functions. We therefore have constructed a model of the presynaptic terminal incorporating vesicular transmitter loading and the presynaptic vesicle cycle. We hypothesize that the experimentally observed synaptic plasticity after changes in transmitter metabolism puts predictable restrictions on vesicle loading, cytoplasmic–vesicular transmitter concentration gradient, and on vesicular cycling or release. The results of our model depend on the specific mechanism linking presynaptic transmitter concentration to vesicular dynamics, that is, alteration of vesicle maturation or alteration of release. It also makes a difference whether differentially filled vesicles are detected and differentially processed within the terminal or whether vesicle filling acts back onto the terminal by presynaptic autoreceptors. Therefore, the model allows one to decide, at a given synapse, how transmitter metabolism is linked to presynaptic function and efficacy.
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Affiliation(s)
- Nikolai Axmacher
- Johannes-Müller-Institut für Physiologie, Humboldt-Universität Berlin, 10117 Berlin, Germany
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Wazlawik E, Morato GS. Influence of drugs acting on nitric oxide-dependent pathways on ethanol tolerance in rats. Psychopharmacology (Berl) 2003; 170:343-50. [PMID: 12955299 DOI: 10.1007/s00213-003-1555-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2002] [Accepted: 05/28/2003] [Indexed: 10/26/2022]
Abstract
RATIONALE Our previous studies have shown that the inhibition of nitric oxide (NO) synthesis with drugs administered either by systemic or ICV routes blocks the development of tolerance to some of the effects of ethanol. OBJECTIVES The aim of this study was to further investigate the role of NO-dependent pathways in tolerance to the incoordinating effect of ethanol through ICV administration of drugs that activate or interfere with NO-dependent pathways. METHODS Male Wistar rats were pretreated with IP ethanol (2.7 g/ kg) or saline before receiving ICV injections of the soluble guanylyl cyclase (sGC) inhibitors methylene blue (30 nmol), 6(phenylamino)-5,8-quinolinedione (LY83583, 10 nmol), 1H-(1,2,4)-oxodiazolo (4,3-a)quinoxalin-1-one (ODQ, 1 nmol), and 4H-8-bromo-1,2,4-oxadiazolo (3,4-d)benz(b)(1,4)oxazin-1-one (NS2028, 10 nmol), or the respective control solutions. The animals were tested on the tilt plane apparatus. Tolerance was assessed 24 h after the first ethanol injection, by administering ethanol to all animals and re-testing them on the tilt plane. The effects of the cyclic guanylate 3',5'-monophosphate (cGMP) analogue, 8-bromo-cGMP (40 nmol or 80 nmol) and of the NO donors S-nitroso-N-acetylpenicillamine (SNAP, 40 or 80 nmol) and sodium nitroprusside (SNP, 40 or 80 nmol) were also studied. RESULTS All sGC inhibitors significantly blocked rapid tolerance, whereas SNP (40 nmol) and 8-bromo-cGMP (80 nmol) increased the magnitude of ethanol tolerance (ANOVA+Tukey's test). CONCLUSIONS The present results suggest that activation or inhibition of NO-dependent pathways increases or blocks rapid tolerance, respectively. These results give additional support to the hypothesis that brain NO plays a role in the development of tolerance to ethanol, but it remains to be confirmed if the same basic cellular mechanisms are also applicable to tolerance to other behavioural and/or physiological effects of this drug.
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Affiliation(s)
- Elisabeth Wazlawik
- Departamento de Farmacologia, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Rua Ferreira Lima 82, 88015-420 Florianopolis, Santa Catarina, Brazil
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