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Wong PY, Fong Z, Hollywood MA, Thornbury KD, Sergeant GP. Regulation of nerve-evoked contractions of the murine vas deferens. Purinergic Signal 2024:10.1007/s11302-024-09993-y. [PMID: 38374492 DOI: 10.1007/s11302-024-09993-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 02/12/2024] [Indexed: 02/21/2024] Open
Abstract
Stimulation of sympathetic nerves in the vas deferens yields biphasic contractions consisting of a rapid transient component resulting from activation of P2X1 receptors by ATP and a secondary sustained component mediated by activation of α1-adrenoceptors by noradrenaline. Noradrenaline can also potentiate the ATP-dependent contractions of the vas deferens, but the mechanisms underlying this effect are unclear. The purpose of the present study was to investigate the mechanisms underlying potentiation of transient contractions of the vas deferens induced by activation of α1-adrenoceptors. Contractions of the mouse vas deferens were induced by electric field stimulation (EFS). Delivery of brief (1s duration) pulses (4 Hz) yielded transient contractions that were inhibited tetrodotoxin (100 nM) and guanethidine (10 µM). α,β-meATP (10 µM), a P2X1R desensitising agent, reduced the amplitude of these responses by 65% and prazosin (100 nM), an α1-adrenoceptor antagonist, decreased mean contraction amplitude by 69%. Stimulation of α1-adrenoceptors with phenylephrine (3 µM) enhanced EFS and ATP-induced contractions and these effects were mimicked by the phorbol ester PDBu (1 µM), which activates PKC. The PKC inhibitor GF109203X (1 µM) prevented the stimulatory effects of PDBu on ATP-induced contractions of the vas deferens but only reduced the stimulatory effects of phenylephrine by 40%. PDBu increased the amplitude of ATP-induced currents recorded from freshly isolated vas deferens myocytes and HEK-293 cells expressing human P2X1Rs by 93%. This study indicates that: (1) potentiation of ATP-evoked contractions of the mouse vas deferens by α1-adrenoceptor activation were not fully blocked by the PKC inhibitor GF109203X and (2) that the stimulatory effect of PKC on ATP-induced contractions of the vas deferens is associated with enhanced P2X1R currents in vas deferens myocytes.
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Affiliation(s)
- Pei Yee Wong
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dublin Road, Dundalk, Co. Louth, Ireland
| | - Zhihui Fong
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, CA, 95616, USA
| | - Mark A Hollywood
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dublin Road, Dundalk, Co. Louth, Ireland
| | - Keith D Thornbury
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dublin Road, Dundalk, Co. Louth, Ireland
| | - Gerard P Sergeant
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dublin Road, Dundalk, Co. Louth, Ireland.
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2
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Babou Kammoe RB, Sévigny J. Extracellular nucleotides in smooth muscle contraction. Biochem Pharmacol 2024; 220:116005. [PMID: 38142836 DOI: 10.1016/j.bcp.2023.116005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 12/26/2023]
Abstract
Extracellular nucleotides and nucleosides are crucial signalling molecules, eliciting diverse biological responses in almost all organs and tissues. These molecules exert their effects by activating specific nucleotide receptors, which are finely regulated by ectonucleotidases that break down their ligands. In this comprehensive review, we aim to elucidate the relevance of extracellular nucleotides as signalling molecules in the context of smooth muscle contraction, considering the modulatory influence of ectonucleotidases on this intricate process. Specifically, we provide a detailed examination of the involvement of extracellular nucleotides in the contraction of non-vascular smooth muscles, including those found in the urinary bladder, the airways, the reproductive system, and the gastrointestinal tract. Furthermore, we present a broader overview of the role of extracellular nucleotides in vascular smooth muscle contraction.
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Affiliation(s)
- Romuald Brice Babou Kammoe
- Centre de Recherche du CHU de Québec - Université Laval, Québec City, QC G1V 4G2, Canada; Département de microbiologie-infectiologie et d'immunologie, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada
| | - Jean Sévigny
- Centre de Recherche du CHU de Québec - Université Laval, Québec City, QC G1V 4G2, Canada; Département de microbiologie-infectiologie et d'immunologie, Faculté de Médecine, Université Laval, Québec City, QC G1V 0A6, Canada.
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3
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Britto-Júnior J, Nacário Silva SG, Lima AT, Fuguhara V, Andrade LB, Mendes GD, Peterson LW, Chiavegatto S, Antunes E, De Nucci G. The pivotal role of neuronal nitric oxide synthase in the release of 6-nitrodopamine from mouse isolated vas deferens. Nitric Oxide 2024; 143:1-8. [PMID: 38096948 DOI: 10.1016/j.niox.2023.12.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 12/08/2023] [Accepted: 12/10/2023] [Indexed: 12/19/2023]
Abstract
6-Nitrodopamine (6-ND) is released from rat and human vas deferens and is considered a major mediator of both tissues contractility. The contractions induced by 6-ND are selectively blocked by both tricyclic antidepressants and α1-adrenoceptor antagonists. Endothelial nitric oxide synthase (eNOS) is the major isoform responsible for 6-ND release in mouse isolated heart, however the origin of 6-ND in the vas deferens is unknown. Here it was investigated by LC-MS/MS the basal release of 6-ND from isolated vas deferens obtained from control, eNOS-/-, nNOS-/-, and iNOS-/- mice. In addition, it was evaluated in vitro vas deferens contractility following electric field stimulation (EFS). Basal release of 6-ND was significantly reduced in nNOS-/- mice compared to control mice, but not decreased when the vas deferens were obtained from either eNOS-/- or iNOS-/- mice. Pre-incubation of the vas deferens with tetrodotoxin (1 μM) significantly reduced the basal release of 6-ND from control, eNOS-/-, and iNOS-/- mice but had no effect on the basal release of 6-ND from nNOS-/- mice. EFS-induced frequency-dependent contractions of the vas deferens, which were significantly reduced when the tissues obtained from control, eNOS-/- and iNOS-/- mice, were pre-incubated with l-NAME, but unaltered when the vas deferens was obtained from nNOS-/- mice. In addition, the EFS-induced contractions were significantly smaller when the vas deferens were obtained from nNOS-/- mice. The results clearly demonstrate that nNOS is the main NO isoform responsible for 6-ND release in mouse vas deferens and reinforces the concept of 6-ND as a major modulator of vas deferens contractility.
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Affiliation(s)
- José Britto-Júnior
- Faculty of Medical Sciences, Department of Pharmacology, University of Campinas (UNICAMP), Campinas, Brazil.
| | | | - Antonio Tiago Lima
- Faculty of Medical Sciences, Department of Pharmacology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Vivian Fuguhara
- Faculty of Medical Sciences, Department of Pharmacology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Larissa Bueno Andrade
- Faculty of Medical Sciences, Department of Pharmacology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Gustavo Duarte Mendes
- Department of Pharmacology, Faculty of Medicine, São Leopoldo Mandic, Campinas, SP, Brazil; Department of Pharmacology, Faculty of Medicine, Metropolitan University of Santos, Santos, SP, Brazil
| | | | - Silvana Chiavegatto
- Department of Pharmacology, Institute of Biomedical Sciences (ICB), University of Sao Paulo (USP), São Paulo, Brazil; Department of Psychiatry, Institute of Psychiatry (IPq), University of Sao Paulo Medical School (FMUSP), São Paulo, Brazil
| | - Edson Antunes
- Faculty of Medical Sciences, Department of Pharmacology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Gilberto De Nucci
- Faculty of Medical Sciences, Department of Pharmacology, University of Campinas (UNICAMP), Campinas, Brazil; Department of Pharmacology, Faculty of Medicine, São Leopoldo Mandic, Campinas, SP, Brazil; Department of Pharmacology, Faculty of Medicine, Metropolitan University of Santos, Santos, SP, Brazil; Department of Pharmacology, Institute of Biomedical Sciences (ICB), University of Sao Paulo (USP), São Paulo, Brazil
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4
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Pampal A, Ozturk Fincan GS, Özen IO, Isli F, Yildirim S, Ercan S, Sarioglu Y. The effects of different vasovasostomy techniques on motility of vas deferens (vas motility following vasovasostomy). World J Urol 2023; 41:3795-3800. [PMID: 37880539 DOI: 10.1007/s00345-023-04668-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 09/27/2023] [Indexed: 10/27/2023] Open
Abstract
PURPOSE Vasovasostomy is used to correct vas deferens (VD) transections encountered during surgery or to reverse sterilization vasectomies. Achieving vasal patency is the primary goal and the success is assessed on various factors including VD patency, flow rates, and pregnancy rates. While preserving vas motility is not a major concern in surgical practice, it is worth noting that VD has peristaltic activity which plays crucial role during ejaculation. Any disruption in its motility could potentially lead to negative outcomes in the future. We conducted an experimental study to assess vas motility changes following vasovasostomy. METHODS The study was approved by Gazi University, Animals Ethic Committee. Twenty-four rats were allocated to four groups. Left-sided VD was harvested in control group (Gr1). The rest of the animals were subjected to transection of VD. Gr2 and 3 underwent microscopic and macroscopic anastomosis, respectively, while Gr4 underwent vasal approximation. After 12 weeks, all left-sided VD were resected, electrical field stimulation (EFS) and exogenous drugs were applied to induce contractions. Statistical analyses were performed and p value < 0.05 was regarded as statistically significant. RESULTS The first and second phases of EFS-induced contractile responses(CR) increased for Gr3 and decreased for Gr4 at submaximal and maximal frequencies. An increase only at maximal frequency for second phase EFS-induced CR was encountered for Gr2. α-β-methylene-ATP-induced CR decreased for Gr3 and 4. Noradrenaline-induced CR increased for Gr2, and 3 and decreased for Gr4. CONCLUSION The results suggest that vasovasostomy performed using a surgical technique that minimizes disruption or damage to VD may have a favorable impact on motility.
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Affiliation(s)
- Arzu Pampal
- Department of Pediatric Surgery, Ankara Training and Research Hospital, Hacettepe Mah. Ulucanlar Cad. No:89, Altındağ, 06230, Ankara, Turkey.
| | | | - Ibrahim Onur Özen
- Department of Pediatric Surgery, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Fatma Isli
- Department of Rational Drug Use, Turkish Medicines and Medical Devices Agency, Ministry of Health, Ankara, Turkey
| | - Seniz Yildirim
- Ankara Numune Health Application and Research Centre, University of Health Sciences, Ankara, Turkey
| | | | - Yusuf Sarioglu
- Departmentof Medical Pharmacology, Faculty of Medicine, Istinye University, Istanbul, Turkey
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Piquer B, Olmos D, Flores A, Barra R, Bahamondes G, Diaz-Araya G, Lara HE. Exposure of the Gestating Mother to Sympathetic Stress Modifies the Cardiovascular Function of the Progeny in Male Rats. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:4285. [PMID: 36901294 PMCID: PMC10002243 DOI: 10.3390/ijerph20054285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/21/2023] [Accepted: 02/25/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Sympathetic stress stimulates norepinephrine (NE) release from sympathetic nerves. During pregnancy, it modifies the fetal environment, increases NE to the fetus through the placental NE transporter, and affects adult physiological functions. Gestating rats were exposed to stress, and then the heart function and sensitivity to in vivo adrenergic stimulation were studied in male progeny. METHODS Pregnant Sprague-Dawley rats were exposed to cold stress (4 °C/3 h/day); rats' male progeny were euthanized at 20 and 60 days old, and their hearts were used to determine the β-adrenergic receptor (βAR) (radioligand binding) and NE concentration. The in vivo arterial pressure response to isoproterenol (ISO, 1 mg/kg weight/day/10 days) was monitored in real time (microchip in the descending aorta). RESULTS Stressed male progeny presented no differences in ventricular weight, the cardiac NE was lower, and high corticosterone plasma levels were recorded at 20 and 60 days old. The relative abundance of β1 adrenergic receptors decreased by 36% and 45%, respectively (p < 0.01), determined by Western blot analysis without changes in β2 adrenergic receptors. A decrease in the ratio between β1/β2 receptors was found. Displacement of 3H-dihydroalprenolol (DHA) from a membrane fraction with propranolol (β antagonist), atenolol (β1 antagonist), or zinterol (β2 agonist) shows decreased affinity but no changes in the β-adrenergic receptor number. In vivo exposure to ISO to induce a β-adrenergic overload provoked death in 50% of stressed males by day 3 of ISO treatment. CONCLUSION These data suggest permanent changes to the heart's adrenergic response after rat progeny were stressed in the uterus.
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Affiliation(s)
- Beatriz Piquer
- Centre for Neurobiochemical Studies in Neuroendocrine Diseases, Laboratory of Neurobiochemistry, Department of Biochemistry and Molecular Biology, Universidad de Chile, Santiago 8380492, Chile
| | - Diandra Olmos
- Centre for Neurobiochemical Studies in Neuroendocrine Diseases, Laboratory of Neurobiochemistry, Department of Biochemistry and Molecular Biology, Universidad de Chile, Santiago 8380492, Chile
| | - Andrea Flores
- Centre for Neurobiochemical Studies in Neuroendocrine Diseases, Laboratory of Neurobiochemistry, Department of Biochemistry and Molecular Biology, Universidad de Chile, Santiago 8380492, Chile
| | - Rafael Barra
- Centre for Neurobiochemical Studies in Neuroendocrine Diseases, Laboratory of Neurobiochemistry, Department of Biochemistry and Molecular Biology, Universidad de Chile, Santiago 8380492, Chile
- Centro de Investigación Biomédica y Aplicada (CIBAP), Escuela de Medicina, Facultad de Ciencias Médicas, Universidad de Santiago de Chile, Santiago 9170020, Chile
| | - Gabriela Bahamondes
- Centre for Neurobiochemical Studies in Neuroendocrine Diseases, Laboratory of Neurobiochemistry, Department of Biochemistry and Molecular Biology, Universidad de Chile, Santiago 8380492, Chile
| | - Guillermo Diaz-Araya
- Department of Chemical Pharmacology and Toxicology, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Santiago 8380492, Chile
| | - Hernan E. Lara
- Centre for Neurobiochemical Studies in Neuroendocrine Diseases, Laboratory of Neurobiochemistry, Department of Biochemistry and Molecular Biology, Universidad de Chile, Santiago 8380492, Chile
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6
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Lima AT, Amorim AC, Britto-Júnior J, Campitelli RR, Fregonesi A, Mónica FZ, Antunes E, De Nucci G. β 1- and β 1/β 2-adrenergic receptor antagonists block 6-nitrodopamine-induced contractions of the rat isolated epididymal vas deferens. Naunyn Schmiedebergs Arch Pharmacol 2022; 395:1257-1268. [PMID: 35798982 DOI: 10.1007/s00210-022-02268-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 06/29/2022] [Indexed: 11/25/2022]
Abstract
6-Nitrodopamine (6-ND) is an endogenous modulator of the contractility in the rat isolated epididymal vas deferens (RIEVD) and considered to be the main peripheral mediator of the emission process. Use of selective and unselective β-adrenergic receptor antagonists has been associated with ejaculatory failure. Here, the effects of selective β1- and β1/β2-adrenergic receptor antagonists on RIEVD contractions induced by 6-ND, dopamine, noradrenaline, adrenaline, and electric-field stimulation (EFS) were investigated. The selective β1-adrenergic receptor antagonists atenolol (0.1 and 1 µM), betaxolol (1 µM), and metoprolol (1 µM) and the unselective β1/β2-adrenergic receptor antagonists propranolol (1 and 10 µM) and pindolol (10 µM) caused significant rightward shifts of the concentration-response curve to 6-ND (pA2 6.41, 6.91, 6.75, 6.47, and 5.74; for atenolol, betaxolol, metoprolol, propranolol, and pindolol), but had no effect on dopamine-, noradrenaline-, and adrenaline-induced contractions. The effects of selective β1- and β1/β2-adrenergic receptor antagonists at a higher concentration (atenolol 1 µM, betaxolol 1 µM, metoprolol 1 µM, propranolol 10 µM, and pindolol 10 µM) also reduced the EFS-induced RIEVD contractions in control, but not in RIEVD obtained from L-NAME-treated animals. The selective β1-adrenoceptor agonist RO-363, the selective β2-adrenoceptor agonist salbutamol, and the selective β3-adrenoceptor agonist mirabegron, up to 300 µM, had no effect on the RIEVD tone. The results demonstrate that β1- and β1-/β2-adrenoceptor receptor antagonists act as 6-ND receptor antagonists in RIEVD, further confirming the main role of 6-ND in the RIEVD contractility.
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Affiliation(s)
- Antonio Tiago Lima
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Rua Tessália Vieira de Camargo, 126 - Cidade Universitária, Campinas, SP, 13083-887, Brazil
| | - Amanda Consulin Amorim
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Rua Tessália Vieira de Camargo, 126 - Cidade Universitária, Campinas, SP, 13083-887, Brazil
| | - José Britto-Júnior
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Rua Tessália Vieira de Camargo, 126 - Cidade Universitária, Campinas, SP, 13083-887, Brazil.
| | - Raquel Rios Campitelli
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Rua Tessália Vieira de Camargo, 126 - Cidade Universitária, Campinas, SP, 13083-887, Brazil
| | - Adriano Fregonesi
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Rua Tessália Vieira de Camargo, 126 - Cidade Universitária, Campinas, SP, 13083-887, Brazil
| | - Fabíola Z Mónica
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Rua Tessália Vieira de Camargo, 126 - Cidade Universitária, Campinas, SP, 13083-887, Brazil
| | - Edson Antunes
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Rua Tessália Vieira de Camargo, 126 - Cidade Universitária, Campinas, SP, 13083-887, Brazil
| | - Gilberto De Nucci
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Rua Tessália Vieira de Camargo, 126 - Cidade Universitária, Campinas, SP, 13083-887, Brazil
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, SP, Brazil
- Faculty of Medical Sciences, Universidade Do Brasil, Fernandópolis, São Paulo, Brazil
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7
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Mazeh AC, Angus JA, Wright CE. Pharmacological characterisation of the CB 1 receptor antagonist activity of cannabidiol in the rat vas deferens bioassay. Eur J Pharmacol 2021; 909:174433. [PMID: 34416240 DOI: 10.1016/j.ejphar.2021.174433] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/08/2021] [Accepted: 08/16/2021] [Indexed: 11/28/2022]
Abstract
Cannabidiol is increasingly considered for treatment of a wide range of medical conditions. Binding studies suggest that cannabidiol binds to CB1 receptors. In the rat isolated vas deferens bioassay, a single electrical pulse causes a biphasic contraction from nerve-released ATP and noradrenaline. WIN 55,212-2 acts on prejunctional CB1 receptors to inhibit release of these transmitters. In this bioassay, we tested whether cannabidiol and SR141716 were acting as competitive antagonists of this receptor. Monophasic contractions mediated by ATP or noradrenaline in the presence of prazosin or NF449 (P2X1 inhibitor), respectively, were measured to a single electrical pulse delivered every 30 min. Following treatment with cannabidiol (10-100 μM) or SR141716 (0.003-10 μM), cumulative concentrations of WIN 55,212-2 (0.001-30 μM) were applied followed by a single electrical pulse. The WIN 55,212-2 concentration-contraction curve EC50 values were applied to global regression analysis to determine the pKB. The antagonist potency of cannabidiol at the CB1 receptor in the rat vas deferens bioassay matched the reported receptor binding affinity. Cannabidiol was a competitive antagonist of WIN 55,212-2 with pKB values of 5.90 when ATP was the effector transmitter and 5.29 when it was noradrenaline. Similarly, SR141716 was a competitive antagonist with pKB values of 8.39 for ATP and 7.67 for noradrenaline as the active transmitter. Cannabidiol's low micromolar CB1 antagonist pKB values suggest that at clinical blood levels (1-3 μM) it may act as a CB1 antagonist at prejunctional neuronal sites with more potency when ATP is the effector than for noradrenaline.
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Affiliation(s)
- Amna C Mazeh
- Cardiovascular Therapeutics Unit, Department of Biochemistry and Pharmacology, University of Melbourne, Victoria, 3010, Australia.
| | - James A Angus
- Cardiovascular Therapeutics Unit, Department of Biochemistry and Pharmacology, University of Melbourne, Victoria, 3010, Australia.
| | - Christine E Wright
- Cardiovascular Therapeutics Unit, Department of Biochemistry and Pharmacology, University of Melbourne, Victoria, 3010, Australia.
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Loesch A. On P2X receptors in the brain: microvessels. Dedicated to the memory of the late Professor Geoffrey Burnstock (1929-2020). Cell Tissue Res 2021; 384:577-588. [PMID: 33755804 DOI: 10.1007/s00441-021-03411-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 01/01/2021] [Indexed: 12/13/2022]
Abstract
This tribute article presents selected immunocytochemical and transmission electron microscope data on the location of ATP-gated P2X receptor in the rat brain, as studied in the 1990s in Prof G. Burnstock's laboratory at University College London. There are examples of immuno-ultrastructural findings and introductory information about pre- and post-synaptic location of P2X receptors in the rat cerebellum and endocrine hypothalamus to support the concept of purinergic transmission in the central nervous system. Then findings of diverse immunoreactivity for P2X1, P2X2, P2X4, and P2X6 receptors associated with brain microvessels are shown, including vascular endothelium and pericytes as well as perivascular astrocytes and neuronal components. These findings imply the involvement of P2X receptors and hence purinergic signalling in the neurovascular unit, at least in microvessels in the rat cerebellum and hypothalamic paraventricular and supraoptic nuclei examined here. Various aspects of P2X receptors in brain microvessels are discussed.
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Affiliation(s)
- Andrzej Loesch
- Centre for Rheumatology and Connective Tissue Diseases, Division of Medicine, University College London Medical School, Royal Free Campus, London, UK.
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9
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Collaço RDC, Hyslop S, Rocha T, Dorce VAC, Rowan EG, Antunes E. Neurotoxicity of Tityus bahiensis (brown scorpion) venom in sympathetic vas deferens preparations and neuronal cells. Arch Toxicol 2020; 94:3315-3327. [PMID: 32548756 PMCID: PMC7415753 DOI: 10.1007/s00204-020-02799-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 05/28/2020] [Indexed: 01/04/2023]
Abstract
Systemic scorpion envenomation is characterized by massive neurotransmitter release from peripheral nerves mediated primarily by scorpion venoms neurotoxins. Tityus bahiensis is one of the medically most important species in Brazil, but its venom pharmacology, especially regarding to peripheral nervous system, is poorly understood. Here, we evaluated the T. bahiensis venom activity on autonomic (sympathetic) neurotransmission by using a variety of approaches, including vas deferens twitch-tension recordings, electrophysiological measurements (resting membrane potentials, spontaneous excitatory junctional potentials and whole-cell patch-clamp), calcium imaging and histomorphological analysis. Low concentrations of venom (≤ 3 μg/mL) facilitated the electrically stimulated vas deferens contractions without affecting postsynaptic receptors or damaging the smooth muscle cells. Transient TTX-sensitive sustained contractions and resting membrane depolarization were mediated mainly by massive spontaneous ATP release. High venom concentrations (≥ 10 μg/mL) blocked the muscle contractions and induced membrane depolarization. In neuronal cells (ND7-23wt), the venom increased the peak sodium current, modified the current-voltage relationship by left-shifting the Nav-channel activation curve, thereby facilitating the opening of these channels. The venom also caused a time-dependent increase in neuronal calcium influx. These results indicate that the sympathetic hyperstimulation observed in systemic envenomation is presynaptically driven, probably through the interaction of α- and β-toxins with neuronal sodium channels.
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Affiliation(s)
- Rita de Cássia Collaço
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, SP, Brazil.
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK.
| | - Stephen Hyslop
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, SP, Brazil
| | - Thalita Rocha
- São Francisco University (USF), Bragança Paulista, SP, Brazil
| | - Valquiria A C Dorce
- Laboratory of Pharmacology, Division for Scientific Development, Butantan Institute, São Paulo, SP, Brazil
| | - Edward G Rowan
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK
| | - Edson Antunes
- Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, SP, Brazil
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10
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Verkhratsky A, Zimmermann H, Abbracchio MP, Illes P, DiVirgilio F. In Memoriam Geoffrey Burnstock: Creator of Purinergic Signaling. FUNCTION 2020. [PMCID: PMC8788863 DOI: 10.1093/function/zqaa006] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Geoff Burnstock (1929–2020) discovered purinergic signaling in a fastidious research that started in early 1960 and culminated in a concept of purinergic nerves in 1972. Subsequently, Geoff developed the concept of purinergic transmission and demonstrated ATP storage, release, and degradation in the context of cotransmission, which was another fundamental concept developed by him. Purinergic transmission contributes to the most fundamental physiological functions such as sensory transduction, regulation of heart rate, smooth muscle contraction, bile secretion, endocrine regulation, immune responses, as well as to various pathophysiological conditions, including inflammation, cancer, neuropathic pain, diabetes, and kidney failure.
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Affiliation(s)
- Alexei Verkhratsky
- Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, M13 9PT, UK
- Achucarro Centre for Neuroscience, IKERBASQUE, 48011 Bilbao, Spain
| | - Herbert Zimmermann
- Institute of Cell Biology and Neuroscience, Molecular and Cellular Neurobiology, Goethe-University, Frankfurt am Main, Germany
| | - Maria P Abbracchio
- Department of Pharmacological Sciences, Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, University of Milan, Milan, Italy
| | - Peter Illes
- Rudolf Boehm Institute for Pharmacology and Toxicology, University of Leipzig, Germany
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11
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Mazeh AC, Angus JA, Wright CE. The effects of varying Mg 2+ ion concentrations on contractions to the cotransmitters ATP and noradrenaline in the rat vas deferens. Auton Neurosci 2019; 222:102588. [PMID: 31669796 DOI: 10.1016/j.autneu.2019.102588] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 08/30/2019] [Accepted: 09/13/2019] [Indexed: 10/25/2022]
Abstract
The vas deferens responds to a single electrical pulse with a biphasic contraction caused by cotransmitters ATP and noradrenaline. Removing Mg2+ (normally 1.2 mM) from the physiological salt solution (PSS) enhances the contraction. This study aimed to determine the effect of Mg2+ concentration on nerve cotransmitter-mediated contractions. Rat vasa deferentia were sequentially bathed in increasing (0, 1.2, 3 mM) or decreasing (3, 1.2, 0 mM) Mg2+ concentrations. At each concentration a single field pulse was applied, and the biphasic contraction recorded. Contractions to exogenous noradrenaline 10 μM and ATP 100 μM were also determined. The biphasic nerve-mediated contraction was elicited by ATP and noradrenaline as NF449 (10 μM) and prazosin (100 nM) completely prevented the respective peaks. Taking the contractions in normal PSS (Mg2+ 1.2 mM) as 100%, lowering Mg2+ to 0 mM enhanced the ATP peak to 170 ± 7% and raising Mg2+ to 3 mM decreased it to 39 ± 3%; the noradrenaline peak was not affected by lowering Mg2+ to 0 mM (97 ± 3%) but was decreased to 63 ± 4% in high Mg2+ (3 mM). Contractions to exogenous ATP, but not noradrenaline, were increased in Mg2+ 0 mM and both were inhibited with Mg2+ 3 mM. Changing Mg2+ concentration affects the contractions elicited by the cotransmitters ATP and noradrenaline. The greatest effects were to potentiate the contraction to ATP in Mg2+ 0 mM and to inhibit the contraction to both ATP and noradrenaline in high Mg2+. Future publications should clearly justify any decision to vary the magnesium concentration from normal (1.2 mM) values.
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Affiliation(s)
- Amna C Mazeh
- Cardiovascular Therapeutics Unit, Department of Pharmacology and Therapeutics, University of Melbourne, Victoria 3010, Australia.
| | - James A Angus
- Cardiovascular Therapeutics Unit, Department of Pharmacology and Therapeutics, University of Melbourne, Victoria 3010, Australia.
| | - Christine E Wright
- Cardiovascular Therapeutics Unit, Department of Pharmacology and Therapeutics, University of Melbourne, Victoria 3010, Australia.
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12
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Yurdakok-Dikmen B, Stelletta C, Tekin K, Kuzukiran O, Daskin A, Filazi A. Effects of phthalates on bovine primary testicular culture and spermatozoa. Cytotechnology 2019; 71:935-947. [PMID: 31451997 DOI: 10.1007/s10616-019-00336-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/12/2019] [Indexed: 10/26/2022] Open
Abstract
Among environmental endocrine-active chemicals, phthalates, commonly known as plasticizers, disrupt the development of the male reproductive tract. In this study, the effects of phthalates (DIBP, BBP, DINP, DBP, DEP, DEHP and DMP) were evaluated on cultures of bovine primary male reproductive cells (n = 3) and spermatozoa (n = 4). Epididymal (caput and corpus epididymis), testicular (parenchymal and mediastinal/tubular) and vas deferens cells (VDC) were prepared from samples collected from slaughterhouse. Second part of caput epididymis which have fewer amount of principal cells, were found to be less affected compared to the first part except DEHP; while corpus epididymis was found to be more affected with IC50 values below 0.976 ng/mL (except for DEP at 4.97 ng/mL). In testicular parenchymal cells, IC50 ranged from 0.15 to 4.11 ng/mL and for mediastinum from 0.01 to 7.31 ng/mL; where cytotoxic effects were more evident in mediastinal section. Least cytotoxic and even proliferational effects (DEHP, DMP and DEP) were observed in VDC, the muscular tube carrying sperm from epididymis to the ejaculatory duct. Least spermiotoxic phthalate was DBP (3.928 ng/mL); while DINP (0.550 ng/mL) induced highest cytotoxic effect on bovine spermatozoa. Differences in the cellular structure and/or the androgen receptor distribution effect the toxicity of phthalates. Our preliminary findings on bovine spermatozoa indicate possible morphological and motility alterations; which challenges further investigation of the transition of phthalates on semen straws used in cryopreservation. Increase of exposure to environmental contaminants raise the issue of the requirement of a new perspective on reproductive health, species and tissue specific differences should further be emphasized.
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Affiliation(s)
- Begum Yurdakok-Dikmen
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Ankara University, Sehit Omer Halis Demir Street, 06110, Diskapi, Ankara, Turkey
| | - Calogero Stelletta
- Clinics in Reproduction, Animal Andrology, University of Padova, Padova, Italy.,Department of Animal Reproduction and Artificial Insemination, Faculty of Veterinary Medicine, Ankara University, 06110, Diskapi, Ankara, Turkey
| | - Koray Tekin
- Department of Animal Reproduction and Artificial Insemination, Faculty of Veterinary Medicine, Ankara University, 06110, Diskapi, Ankara, Turkey
| | - Ozgur Kuzukiran
- Veterinary Department, Eldivan Vocational School of Health Services, Cankiri Karatekin University, 18100, Cankiri, Turkey
| | - Ali Daskin
- Department of Animal Reproduction and Artificial Insemination, Faculty of Veterinary Medicine, Ankara University, 06110, Diskapi, Ankara, Turkey
| | - Ayhan Filazi
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Ankara University, Sehit Omer Halis Demir Street, 06110, Diskapi, Ankara, Turkey.
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13
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Svensson E, Apergis-Schoute J, Burnstock G, Nusbaum MP, Parker D, Schiöth HB. General Principles of Neuronal Co-transmission: Insights From Multiple Model Systems. Front Neural Circuits 2019; 12:117. [PMID: 30728768 PMCID: PMC6352749 DOI: 10.3389/fncir.2018.00117] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 12/14/2018] [Indexed: 12/22/2022] Open
Abstract
It is now accepted that neurons contain and release multiple transmitter substances. However, we still have only limited insight into the regulation and functional effects of this co-transmission. Given that there are 200 or more neurotransmitters, the chemical complexity of the nervous system is daunting. This is made more-so by the fact that their interacting effects can generate diverse non-linear and novel consequences. The relatively poor history of pharmacological approaches likely reflects the fact that manipulating a transmitter system will not necessarily mimic its roles within the normal chemical environment of the nervous system (e.g., when it acts in parallel with co-transmitters). In this article, co-transmission is discussed in a range of systems [from invertebrate and lower vertebrate models, up to the mammalian peripheral and central nervous system (CNS)] to highlight approaches used, degree of understanding, and open questions and future directions. Finally, we offer some outlines of what we consider to be the general principles of co-transmission, as well as what we think are the most pressing general aspects that need to be addressed to move forward in our understanding of co-transmission.
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Affiliation(s)
- Erik Svensson
- BMC, Department of Neuroscience, Functional Pharmacology, Uppsala University, Uppsala, Sweden
| | - John Apergis-Schoute
- Department of Neurosciences, Psychology and Behaviour, University of Leicester, Leicester, United Kingdom
| | - Geoffrey Burnstock
- Department of Pharmacology and Therapeutics, University of Melbourne, Melbourne, VIC, Australia
| | - Michael P Nusbaum
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - David Parker
- Department of Physiology, Development and Neuroscience, Faculty of Biology, University of Cambridge, Cambridge, United Kingdom
| | - Helgi B Schiöth
- BMC, Department of Neuroscience, Functional Pharmacology, Uppsala University, Uppsala, Sweden.,Institute for Translational Medicine and Biotechnology, Sechenov First Moscow State Medical University, Moscow, Russia
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Baker D, Pryce G, Visintin C, Sisay S, Bondarenko AI, Vanessa Ho WS, Jackson SJ, Williams TE, Al-Izki S, Sevastou I, Okuyama M, Graier WF, Stevenson LA, Tanner C, Ross R, Pertwee RG, Henstridge CM, Irving AJ, Schulman J, Powell K, Baker MD, Giovannoni G, Selwood DL. Big conductance calcium-activated potassium channel openers control spasticity without sedation. Br J Pharmacol 2017; 174:2662-2681. [PMID: 28677901 PMCID: PMC5522996 DOI: 10.1111/bph.13889] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 04/27/2017] [Accepted: 05/17/2017] [Indexed: 12/19/2022] Open
Abstract
Background and Purpose Our initial aim was to generate cannabinoid agents that control spasticity, occurring as a consequence of multiple sclerosis (MS), whilst avoiding the sedative side effects associated with cannabis. VSN16R was synthesized as an anandamide (endocannabinoid) analogue in an anti‐metabolite approach to identify drugs that target spasticity. Experimental Approach Following the initial chemistry, a variety of biochemical, pharmacological and electrophysiological approaches, using isolated cells, tissue‐based assays and in vivo animal models, were used to demonstrate the activity, efficacy, pharmacokinetics and mechanism of action of VSN16R. Toxicological and safety studies were performed in animals and humans. Key Results VSN16R had nanomolar activity in tissue‐based, functional assays and dose‐dependently inhibited spasticity in a mouse experimental encephalomyelitis model of MS. This effect occurred with over 1000‐fold therapeutic window, without affecting normal muscle tone. Efficacy was achieved at plasma levels that are feasible and safe in humans. VSN16R did not bind to known CB1/CB2/GPPR55 cannabinoid‐related receptors in receptor‐based assays but acted on a vascular cannabinoid target. This was identified as the major neuronal form of the big conductance, calcium‐activated potassium (BKCa) channel. Drug‐induced opening of neuronal BKCa channels induced membrane hyperpolarization, limiting excessive neural‐excitability and controlling spasticity. Conclusions and Implications We identified the neuronal form of the BKCa channel as the target for VSN16R and demonstrated that its activation alleviates neuronal excitability and spasticity in an experimental model of MS, revealing a novel mechanism to control spasticity. VSN16R is a potential, safe and selective ligand for controlling neural hyper‐excitability in spasticity.
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Affiliation(s)
- David Baker
- Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK.,Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, UK
| | - Gareth Pryce
- Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK.,Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, UK
| | - Cristina Visintin
- Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, UK.,Department of Medicinal Chemistry, UCL Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Sofia Sisay
- Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Alexander I Bondarenko
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria.,A.A. Bogomoletz Institute of Physiology, Kiev, Ukraine
| | - W S Vanessa Ho
- Vascular Biology Research Centre. St. George's, University of London, London, UK
| | - Samuel J Jackson
- Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Thomas E Williams
- Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Sarah Al-Izki
- Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Ioanna Sevastou
- Department of Medicinal Chemistry, UCL Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Masahiro Okuyama
- Department of Medicinal Chemistry, UCL Wolfson Institute for Biomedical Research, University College London, London, UK
| | - Wolfgang F Graier
- Institute of Molecular Biology and Biochemistry, Medical University of Graz, Graz, Austria
| | - Lesley A Stevenson
- Vascular Biology Research Centre. St. George's, University of London, London, UK
| | - Carolyn Tanner
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Ruth Ross
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Roger G Pertwee
- Department of Biomedical Sciences, Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
| | - Christopher M Henstridge
- Neurosciences Institute, Division of Pathology and Neuroscience, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
| | - Andrew J Irving
- Neurosciences Institute, Division of Pathology and Neuroscience, Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
| | - Jesse Schulman
- Canbex Therapeutics Ltd, London BioScience Innovation Centre, London, UK
| | - Keith Powell
- Canbex Therapeutics Ltd, London BioScience Innovation Centre, London, UK
| | - Mark D Baker
- Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Gavin Giovannoni
- Neuroimmunology Unit, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK.,Department of Neuroinflammation, UCL Institute of Neurology, University College London, London, UK
| | - David L Selwood
- Department of Medicinal Chemistry, UCL Wolfson Institute for Biomedical Research, University College London, London, UK
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15
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Burnstock G, Loesch A. Sympathetic innervation of the kidney in health and disease: Emphasis on the role of purinergic cotransmission. Auton Neurosci 2017; 204:4-16. [DOI: 10.1016/j.autneu.2016.05.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 05/27/2016] [Accepted: 05/29/2016] [Indexed: 11/29/2022]
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16
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Effects of in vitro, acute and chronic treatment with fluoxetine on the sympathetic neurotransmission of rat vas deferens. Auton Neurosci 2017; 203:17-24. [DOI: 10.1016/j.autneu.2016.10.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 09/26/2016] [Accepted: 10/24/2016] [Indexed: 11/24/2022]
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17
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Bomfim GHS, García García A, Jurkiewicz A, Jurkiewicz NH. Relationship between central behavioral effects and peripheral sympathetic neurotransmission functionality during acute cocaine withdrawal syndrome in adult rats. THE AMERICAN JOURNAL OF DRUG AND ALCOHOL ABUSE 2015; 42:63-76. [PMID: 26579734 DOI: 10.3109/00952990.2015.1094082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Acute cocaine withdrawal syndrome (ACWS) is characterized as a set of organic alterations triggered by abrupt discontinuation of chronic cocaine consumption, usually occurring at 24-40 hours after withdrawal. However, little is known about the relationship between central and peripheral sympathetic neurotransmission during ACWS. OBJECTIVE AND METHODS We investigated the mechanisms involved in central and peripheral sympathetic neurotransmission and how ACWS affects the sympathetic functionality. Cocaine was administered twice daily for 5 days in Wistar rats (at least 5 in each group): on the first and second day, 15 mg/kg/i.p.; third day, 20 mg/kg/i.p.; and finally in the last two days, 30 mg/kg/i.p. Subsequently, at 1, 24, 48 and 120 h after cocaine administration the following experiments were done: (i) at the central level, behavioral tests of open-field and elevated plus maze; and (ii) at the peripheral level, tests of catecholamine release, function of α2-adrenergic receptors (α2-ARs), imidazoline receptors (I(1,2)-Rs), L-type voltage-gated (Ca(v1.2)) Ca(2+) channels and α1-ARs. RESULTS During ACWS, rats showed hypolocomotion and exacerbation of anxiogenic-effects 24 h after cocaine withdrawal. Likewise, a decrease in the catecholamine release and activity of α2-ARs/I(1,2)-Rs at 24-48 h after cocaine withdrawal was observed. A decrease in Ca(v1.2) channels and α1-ARs function at 48 h after cocaine withdrawal was observed. CONCLUSIONS The relationship of central and peripheral sympathetic neurotransmission during ACWS possibly due to a failure in activation and/or inactivation of presynaptic α2-ARs/I(1,2)-Rs, may offer a potential target for attenuating ACWS.
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Affiliation(s)
| | - Antonio García García
- b Instituto Teófilo Hernando del Medicamento , Universidad Autónoma de Madrid , Madrid , Spain
| | - Aron Jurkiewicz
- a Department of Pharmacology , Escola Paulista de Medicina, Universidade Federal de São Paulo , Brazil
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18
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Wallace A, Gabriel D, McHale NG, Hollywood MA, Thornbury KD, Sergeant GP. Regulation of nerve-evoked contractions of rabbit vas deferens by acetylcholine. Physiol Rep 2015; 3:3/9/e12520. [PMID: 26359240 PMCID: PMC4600378 DOI: 10.14814/phy2.12520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Stimulation of intramural nerves in the vas deferens of many species yields a classical biphasic contraction comprised of an initial fast component, mediated by P2X receptors and a second slower component, mediated by α1-adrenoceptors. It is also recognized that sympathetic nerve-mediated contractions of the vas deferens can be modulated by acetylcholine (Ach), however there is considerable disagreement in the literature regarding the precise contribution of cholinergic nerves to contraction of the vas deferens. In this study we examined the effect of cholinergic modulators on electric field stimulation (EFS)-evoked contractions of rabbit vas deferens and on cytosolic Ca(2+) levels in isolated vas deferens smooth muscle cells (VDSMC). The sustained component of EFS-evoked contractions was inhibited by atropine and by the selective M3R antagonist, 1,1-dimethyl-4-diphenylacetoxypiperidinium iodide (4-DAMP). EFS-evoked contractions were potentiated by Ach, carbachol (Cch), and neostigmine. The sustained phase of the EFS-evoked contraction was inhibited by prazosin, an α1-adrenoceptor antagonist and guanethidine, an inhibitor of noradrenaline release, even in the continued presence of Ach, Cch or neostigmine. The soluble guanylate cyclase (sGC) inhibitor, 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one enhanced the amplitude of EFS-evoked contractions and reduced the inhibitory effects of 4-DAMP. Isolated VDSMC displayed spontaneous Ca(2+) oscillations, but did not respond to Cch. However, the α1-adrenoceptor agonist, phenylephrine, evoked a Ca(2+) transient and contracted the cells. These data suggest that EFS-evoked contractions of the rabbit vas deferens are potentiated by activation of M3 receptors and reduced by activation of a sGC-dependent inhibitory pathway.
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Affiliation(s)
- Audrey Wallace
- The Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Co. Louth, Ireland
| | - Deborah Gabriel
- The Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Co. Louth, Ireland
| | - Noel G McHale
- The Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Co. Louth, Ireland
| | - Mark A Hollywood
- The Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Co. Louth, Ireland
| | - Keith D Thornbury
- The Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Co. Louth, Ireland
| | - Gerard P Sergeant
- The Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Co. Louth, Ireland
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19
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Burnstock G, Dale N. Purinergic signalling during development and ageing. Purinergic Signal 2015; 11:277-305. [PMID: 25989750 PMCID: PMC4529855 DOI: 10.1007/s11302-015-9452-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 04/23/2015] [Indexed: 01/28/2023] Open
Abstract
Extracellular purines and pyrimidines play major roles during embryogenesis, organogenesis, postnatal development and ageing in vertebrates, including humans. Pluripotent stem cells can differentiate into three primary germ layers of the embryo but may also be involved in plasticity and repair of the adult brain. These cells express the molecular components necessary for purinergic signalling, and their developmental fates can be manipulated via this signalling pathway. Functional P1, P2Y and P2X receptor subtypes and ectonucleotidases are involved in the development of different organ systems, including heart, blood vessels, skeletal muscle, urinary bladder, central and peripheral neurons, retina, inner ear, gut, lung and vas deferens. The importance of purinergic signalling in the ageing process is suggested by changes in expression of A1 and A2 receptors in old rat brains and reduction of P2X receptor expression in ageing mouse brain. By contrast, in the periphery, increases in expression of P2X3 and P2X4 receptors are seen in bladder and pancreas.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London, NW3 2PF, UK,
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20
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Cardoso AM, Schetinger MRC, Correia-de-Sá P, Sévigny J. Impact of ectonucleotidases in autonomic nervous functions. Auton Neurosci 2015; 191:25-38. [PMID: 26008223 DOI: 10.1016/j.autneu.2015.04.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Revised: 04/28/2015] [Accepted: 04/29/2015] [Indexed: 01/05/2023]
Abstract
Adenine and uracil nucleotides play key functions in the autonomic nervous system (ANS). For instance, ATP acts as a neurotransmitter, co-transmitter and neuromodulator in the ANS. The purinergic system encompasses (1) receptors that respond to extracellular purines, which are designated as P1 and P2 purinoceptors, (2) purine release and uptake, and (3) a cascade of enzymes that regulate the concentration of purines near the cell surface. Ectonucleotidases and adenosine deaminase (ADA) are enzymes responsible for the hydrolysis of ATP (and other nucleotides such as ADP, UTP, UDP, AMP) and adenosine, respectively. Accordingly, these enzymes are expected to play an important role in the control of neuro-effector transmission in tissues innervated by both the sympathetic and parasympathetic divisions of the ANS. Indeed, ectonucleotidases have the ability to either terminate P2 receptor responses initiated by nucleoside triphosphates (ATP and UTP), and/or to favor the activation of ADP (e.g. P2Y1,12,13) and UDP (e.g. P2Y6) and/or adenosine (P1) specific receptors. In addition, ectonucleotidases can also importantly protect some P2 receptors from desensitization (e.g. P2X1, P2Y1). In this review, we present the (putative) roles of ectonucleotidases and ADA in the ANS with a focus on their regulatory activity at neuro-effector junctions in the following tissues: heart, vas deferens, urinary bladder, salivary glands, blood vessels and the intestine. We also present their implication in nociceptive transmission.
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Affiliation(s)
- Andréia Machado Cardoso
- Post-Graduation Program in Toxicological Biochemistry, Department of Biochemistry and Molecular Biology of the Center of Natural and Exact Sciences of the Federal University of Santa Maria, Santa Maria Rio Grande do Sul, Brazil; Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec City, Québec G1V 0A6, Canada; Centre de Recherche du CHU de Québec - Université Laval, Québec G1V 4G2, Canada.
| | - Maria Rosa Chitolina Schetinger
- Post-Graduation Program in Toxicological Biochemistry, Department of Biochemistry and Molecular Biology of the Center of Natural and Exact Sciences of the Federal University of Santa Maria, Santa Maria Rio Grande do Sul, Brazil
| | - Paulo Correia-de-Sá
- Laboratório de Farmacologia e Neurobiologia, MedInUP, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto (UP), 4050-313 Porto, Portugal
| | - Jean Sévigny
- Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec City, Québec G1V 0A6, Canada; Centre de Recherche du CHU de Québec - Université Laval, Québec G1V 4G2, Canada.
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21
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Mutafova-Yambolieva VN, Durnin L. The purinergic neurotransmitter revisited: a single substance or multiple players? Pharmacol Ther 2014; 144:162-91. [PMID: 24887688 PMCID: PMC4185222 DOI: 10.1016/j.pharmthera.2014.05.012] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Accepted: 05/23/2014] [Indexed: 12/20/2022]
Abstract
The past half century has witnessed tremendous advances in our understanding of extracellular purinergic signaling pathways. Purinergic neurotransmission, in particular, has emerged as a key contributor in the efficient control mechanisms in the nervous system. The identity of the purine neurotransmitter, however, remains controversial. Identifying it is difficult because purines are present in all cell types, have a large variety of cell sources, and are released via numerous pathways. Moreover, studies on purinergic neurotransmission have relied heavily on indirect measurements of integrated postjunctional responses that do not provide direct information for neurotransmitter identity. This paper discusses experimental support for adenosine 5'-triphosphate (ATP) as a neurotransmitter and recent evidence for possible contribution of other purines, in addition to or instead of ATP, in chemical neurotransmission in the peripheral, enteric and central nervous systems. Sites of release and action of purines in model systems such as vas deferens, blood vessels, urinary bladder and chromaffin cells are discussed. This is preceded by a brief discussion of studies demonstrating storage of purines in synaptic vesicles. We examine recent evidence for cell type targets (e.g., smooth muscle cells, interstitial cells, neurons and glia) for purine neurotransmitters in different systems. This is followed by brief discussion of mechanisms of terminating the action of purine neurotransmitters, including extracellular nucleotide hydrolysis and possible salvage and reuptake in the cell. The significance of direct neurotransmitter release measurements is highlighted. Possibilities for involvement of multiple purines (e.g., ATP, ADP, NAD(+), ADP-ribose, adenosine, and diadenosine polyphosphates) in neurotransmission are considered throughout.
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Affiliation(s)
| | - Leonie Durnin
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557, United States
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22
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Influence of acute treatment with sibutramine on the sympathetic neurotransmission of the young rat vas deferens. Eur J Pharmacol 2014; 738:118-24. [PMID: 24886880 DOI: 10.1016/j.ejphar.2014.05.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 05/07/2014] [Accepted: 05/19/2014] [Indexed: 11/21/2022]
Abstract
The effects of acute treatment with sibutramine on the peripheral sympathetic neurotransmission in vas deferens of young rats were still not evaluated. Therefore, we carried out this study in order to verify the effects of acute sibutramine treatment on the neuronal- and exogenous agonist-induced contractions of the young rat vas deferens. Young 45-day-old male Wistar rats were pretreated with sibutramine 6 mg/kg and after 4h the vas deferens was used for experiment. The acute treatment with sibutramine was able to increase the potency (pD2) of noradrenaline and phenylephrine. Moreover, the efficacy (Emax) of noradrenaline was increased while the efficacy of serotonin and nicotine were decreased. The maximum effect induced by a single concentration of tyramine was diminished in the vas deferens from treated group. Moreover, the leftward shift of the noradrenaline curves promoted by uptake blockers (cocaine and corticosterone) and β-adrenoceptor antagonist (propranolol) was reduced in the vas deferens of treated group. The initial phasic and secondary tonic components of the neuronal-evoked contractions of vas deferens from treated group at the frequencies of 2 Hz were decreased. Moreover, only the initial phasic component at 5 Hz was diminished by the acute treatment with sibutramine. In conclusion, we showed that the acute treatment with sibutramine in young rats was able to affect the peripheral sympathetic nervous system by inhibition of noradrenaline uptake and reduction of the neuronal content of this neurotransmitter, leading to an enhancement of vas deferens sensitivity to noradrenaline.
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Kauffenstein G, Pelletier J, Lavoie EG, Kukulski F, Martín-Satué M, Dufresne SS, Frenette J, Ribas Fürstenau C, Sereda MJ, Toutain B, Henrion D, Sullivan R, Vial C, Sévigny J. Nucleoside triphosphate diphosphohydrolase-1 ectonucleotidase is required for normal vas deferens contraction and male fertility through maintaining P2X1 receptor function. J Biol Chem 2014; 289:28629-39. [PMID: 25160621 DOI: 10.1074/jbc.m114.604082] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In this work, we report that Entpd1(-/-) mice, deficient for the ectonucleotidase nucleoside triphosphate diphosphohydrolase-1 (NTPDase1), produce smaller litters (27% reduction) compared with wild-type C57BL6 animals. This deficit is linked to reduced in vivo oocyte fertilization by Entpd1(-/-) males (61 ± 11% versus 88 ± 7% for Entpd1(+/+)). Normal epididymal sperm count, spermatozoa morphology, capacitation, and motility and reduced ejaculated sperm number (2.4 ± 0.5 versus 3.7 ± 0.4 million for Entpd1(+/+)) pointed to vas deferens dysfunction. NTPDase1 was localized by immunofluorescence in the tunica muscularis of the vas deferens. Its absence resulted in a major ATP hydrolysis deficiency, as observed in situ by histochemistry and in primary smooth muscle cell cultures. In vitro, Entpd1(-/-) vas deferens displayed an exacerbated contraction to ATP, a diminished response to its non-hydrolysable analog αβMeATP, and a reduced contraction to electrical field stimulation, suggesting altered P2X1 receptor function with a propensity to desensitize. This functional alteration was accompanied by a 3-fold decrease in P2X1 protein expression in Entpd1(-/-) vas deferens with no variation in mRNA levels. Accordingly, exogenous nucleotidase activity was required to fully preserve P2X1 receptor activation by ATP in vitro. Our study demonstrates that NTPDase1 is required to maintain normal P2X1 receptor functionality in the vas deferens and that its absence leads to impaired peristalsis, reduced spermatozoa concentration in the semen, and, eventually, reduced fertility. This suggests that alteration of NTPDase1 activity affects ejaculation efficacy and male fertility. This work may contribute to unveil a cause of infertility and open new therapeutic potentials.
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Affiliation(s)
- Gilles Kauffenstein
- From the Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec G1V 0A6, Canada, the Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec G1V 4G2, Canada, the Unité mixte de recherche CNRS 6214 INSERM U1083, Université d'Angers, 49045 Angers, France,
| | - Julie Pelletier
- the Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec G1V 4G2, Canada
| | - Elise G Lavoie
- From the Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec G1V 0A6, Canada, the Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec G1V 4G2, Canada
| | - Filip Kukulski
- From the Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec G1V 0A6, Canada, the Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec G1V 4G2, Canada
| | - Mireia Martín-Satué
- From the Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec G1V 0A6, Canada, the Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec G1V 4G2, Canada, the Departament de Patologia i Terapèutica Experimental, Facultat de Medicina, Universitat de Barcelona, 08907 Barcelona, Spain
| | - Sébastien S Dufresne
- the Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec G1V 4G2, Canada, the Département de Réadaptation, Faculté de Médecine, Université Laval, Québec G1V 0A6, Canada
| | - Jérôme Frenette
- the Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec G1V 4G2, Canada, the Département de Réadaptation, Faculté de Médecine, Université Laval, Québec G1V 0A6, Canada
| | - Cristina Ribas Fürstenau
- From the Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec G1V 0A6, Canada, the Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec G1V 4G2, Canada
| | - Michal J Sereda
- the Department of Cell Physiology and Pharmacology, University of Leicester, Leicester LE1 9HN, United Kingdom, and
| | - Bertrand Toutain
- the Unité mixte de recherche CNRS 6214 INSERM U1083, Université d'Angers, 49045 Angers, France
| | - Daniel Henrion
- the Unité mixte de recherche CNRS 6214 INSERM U1083, Université d'Angers, 49045 Angers, France
| | - Robert Sullivan
- the Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec G1V 4G2, Canada, the Department of Obstetrics, Gynecology, and Reproduction, Faculté de Médecine, Université Laval, Québec G1V 0A6, Canada
| | - Catherine Vial
- the Department of Cell Physiology and Pharmacology, University of Leicester, Leicester LE1 9HN, United Kingdom, and
| | - Jean Sévigny
- From the Département de Microbiologie-Infectiologie et d'Immunologie, Faculté de Médecine, Université Laval, Québec G1V 0A6, Canada, the Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec G1V 4G2, Canada,
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Ferreira Verde L, Silva Lopes G, Miki Ihara SS, Hyppolito Jurkiewicz N, Jurkiewicz A. Acute treatment with alcohol affects calcium signaling and contraction associated with apoptosis in vas deferens of periadolescent rats. Eur J Pharmacol 2014; 735:211-8. [DOI: 10.1016/j.ejphar.2014.04.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 04/04/2014] [Accepted: 04/07/2014] [Indexed: 12/19/2022]
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Navarrete LC, Barrera NP, Huidobro-Toro JP. Vas deferens neuro-effector junction: from kymographic tracings to structural biology principles. Auton Neurosci 2014; 185:8-28. [PMID: 24956963 DOI: 10.1016/j.autneu.2014.05.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 05/14/2014] [Accepted: 05/20/2014] [Indexed: 11/29/2022]
Abstract
The vas deferens is a simple bioassay widely used to study the physiology of sympathetic neurotransmission and the pharmacodynamics of adrenergic drugs. The role of ATP as a sympathetic co-transmitter has gained increasing attention and furthered our understanding of its role in sympathetic reflexes. In addition, new information has emerged on the mechanisms underlying the storage and release of ATP. Both noradrenaline and ATP concur to elicit the tissue smooth muscle contractions following sympathetic reflexes or electrical field stimulation of the sympathetic nerve terminals. ATP and adenosine (its metabolic byproduct) are powerful presynaptic regulators of co-transmitter actions. In addition, neuropeptide Y, the third member of the sympathetic triad, is an endogenous modulator. The peptide plus ATP and/or adenosine play a significant role as sympathetic modulators of transmitter's release. This review focuses on the physiological principles that govern sympathetic co-transmitter activity, with special interest in defining the motor role of ATP. In addition, we intended to review the recent structural biology findings related to the topology of the P2X1R based on the crystallized P2X4 receptor from Danio rerio, or the crystallized adenosine A2A receptor as a member of the G protein coupled family of receptors as prototype neuro modulators. This review also covers structural elements of ectonucleotidases, since some members are found in the vas deferens neuro-effector junction. The allosteric principles that apply to purinoceptors are also reviewed highlighting concepts derived from receptor theory at the light of the current available structural elements. Finally, we discuss clinical applications of these concepts.
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Affiliation(s)
- L Camilo Navarrete
- Laboratorio de Estructura de Proteínas de Membrana y Señalización, Núcleo Milenio de Biología Estructural, NuBEs, Facultad de Ciencias Biológicas, P. Universidad Católica de Chile, Chile
| | - Nelson P Barrera
- Laboratorio de Estructura de Proteínas de Membrana y Señalización, Núcleo Milenio de Biología Estructural, NuBEs, Facultad de Ciencias Biológicas, P. Universidad Católica de Chile, Chile
| | - J Pablo Huidobro-Toro
- Laboratorio de Nucleótidos, Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Chile.
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26
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McManus JM, Lu H, Cullins MJ, Chiel HJ. Differential activation of an identified motor neuron and neuromodulation provide Aplysia's retractor muscle an additional function. J Neurophysiol 2014; 112:778-91. [PMID: 24805081 DOI: 10.1152/jn.00148.2014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
To survive, animals must use the same peripheral structures to perform a variety of tasks. How does a nervous system employ one muscle to perform multiple functions? We addressed this question through work on the I3 jaw muscle of the marine mollusk Aplysia californica's feeding system. This muscle mediates retraction of Aplysia's food grasper in multiple feeding responses and is innervated by a pool of identified neurons that activate different muscle regions. One I3 motor neuron, B38, is active in the protraction phase, rather than the retraction phase, suggesting the muscle has an additional function. We used intracellular, extracellular, and muscle force recordings in several in vitro preparations as well as recordings of nerve and muscle activity from intact, behaving animals to characterize B38's activation of the muscle and its activity in different behavior types. We show that B38 specifically activates the anterior region of I3 and is specifically recruited during one behavior, swallowing. The function of this protraction-phase jaw muscle contraction is to hold food; thus the I3 muscle has an additional function beyond mediating retraction. We additionally show that B38's typical activity during in vivo swallowing is insufficient to generate force in an unmodulated muscle and that intrinsic and extrinsic modulation shift the force-frequency relationship to allow contraction. Using methods that traverse levels from individual neuron to muscle to intact animal, we show how regional muscle activation, differential motor neuron recruitment, and neuromodulation are key components in Aplysia's generation of multifunctionality.
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Affiliation(s)
- Jeffrey M McManus
- Department of Biology, Case Western Reserve University, Cleveland, Ohio
| | - Hui Lu
- Department of Biology, Case Western Reserve University, Cleveland, Ohio
| | - Miranda J Cullins
- Department of Biology, Case Western Reserve University, Cleveland, Ohio
| | - Hillel J Chiel
- Department of Biology, Case Western Reserve University, Cleveland, Ohio; Department of Neurosciences, Case Western Reserve University, Cleveland, Ohio; and Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio
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27
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Burnstock G. Purinergic signalling in the reproductive system in health and disease. Purinergic Signal 2014; 10:157-87. [PMID: 24271059 PMCID: PMC3944041 DOI: 10.1007/s11302-013-9399-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 10/24/2013] [Indexed: 12/16/2022] Open
Abstract
There are multiple roles for purinergic signalling in both male and female reproductive organs. ATP, released as a cotransmitter with noradrenaline from sympathetic nerves, contracts smooth muscle via P2X1 receptors in vas deferens, seminal vesicles, prostate and uterus, as well as in blood vessels. Male infertility occurs in P2X1 receptor knockout mice. Both short- and long-term trophic purinergic signalling occurs in reproductive organs. Purinergic signalling is involved in hormone secretion, penile erection, sperm motility and capacitation, and mucous production. Changes in purinoceptor expression occur in pathophysiological conditions, including pre-eclampsia, cancer and pain.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London, NW3 2PF, UK,
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28
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Vyas BA, Desai NY, Patel PK, Joshi SV, Shah DR. Effect of Boerhaavia diffusa in experimental prostatic hyperplasia in rats. Indian J Pharmacol 2014; 45:264-9. [PMID: 23833370 PMCID: PMC3696298 DOI: 10.4103/0253-7613.111946] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Revised: 12/14/2012] [Accepted: 02/26/2013] [Indexed: 11/09/2022] Open
Abstract
Objective: Present investigation was undertaken to study the effectiveness of hydroalcoholic extract of roots of Boerhaavia diffusa in experimental benign prostatic hyperplasia (BPH) in rats using various animal models. Materials and Methods: BPH in rats was induced by subcutaneous injection of testosterone (5 mg/kg) daily for 28 days. Rats were divided in to five groups (six rats each). A negative control group received arachis oil (1 ml/kg s.c.) and four groups were injected testosterone. These four groups were further divided into reference group (finasteride 1 mg/kg), model group (testosterone), study group A (B. diffusa 100 mg/kg), and study group B (B. diffusa 250 mg/kg). On the 29th day, rats were sacrificed and body weight, prostate weight, bladder weight, and serum testosterone level were measured and histological studies were carried out. Further in vitro analysis of B. diffusa extract on contractility of isolated rat vas deferens and prostate gland, produced by exogenously administered agonists were carried out. All results were expressed as mean ± SEM. 0 Data were analyzed by one-way analysis of variance followed by Tukey's test. Results: B. diffusa (100 mg/kg) treatment for 28 days resulted in significant inhibition of prostate growth (P < 0.05). Drug extract did not have significant change on serum testosterone level. Histopathological analysis of prostate gland supported above results. Results of in vitro experiment suggest that extracts had attenuated the contractile responses of isolated vas deferens and prostate gland to exogenously applied agonists. Conclusion: The results suggested that treatment with B. diffusa may improve symptoms of disease and inhibit the increased prostate size. In vitro study implies that herbal extracts has the machinery to produce beneficial effect on prostatic smooth muscle, which would relieve the urinary symptoms of disease. B. diffusa could be a potential source of new treatment of prostatic hyperplasia.
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Affiliation(s)
- Bhavin A Vyas
- Department of Pharmacology, Maliba Pharmacy College, Bardoli, Mahuva Road, Surat, Gujarat, India
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29
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Vladimirova IA, Lankin YN, Philyppov IB, Sushiy LF, Shuba YM. Frequency dependence of excitation–contraction of multicellular smooth muscle preparations: the relevance to bipolar electrosurgery. J Surg Res 2014; 186:119-25. [DOI: 10.1016/j.jss.2013.08.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 07/22/2013] [Accepted: 08/12/2013] [Indexed: 11/27/2022]
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30
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Abstract
Ejaculatory dysfunction may occur after many different disorders ranging from traumatic spinal cord injury to diabetes mellitus. With an understanding of the many facets and nuances of the ejaculatory apparatus, both anatomic and neurologic, the well-versed clinician can proceed along a safe, efficient, and appropriate treatment algorithm to help affected men and their partners achieve parenthood.
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Affiliation(s)
- Elizabeth Phillips
- Division of Urology, Boston University School of Medicine, Shapiro Center, Suite 3B, 715 Albany Street, Boston, MA 02118, USA
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31
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Koslov DS, Andersson KE. Physiological and pharmacological aspects of the vas deferens-an update. Front Pharmacol 2013; 4:101. [PMID: 23986701 PMCID: PMC3749770 DOI: 10.3389/fphar.2013.00101] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 07/29/2013] [Indexed: 12/22/2022] Open
Abstract
The vas deferens, a muscular conduit conveying spermatozoa from the epididymis to the urethra, has been used as a model tissue for smooth muscle pharmacological and physiological advancements. Many drugs, notably α-adrenergic antagonists, have effects on contractility and thus normal ejaculation, incurring significant side effects for patients that may interfere with compliance. A more thorough understanding of the innervation and neurotransmitter pharmacology of the vas has indicated that this is a highly complex structure and a model for co-transmission at the synapse. Recent models have shown clinical scenarios that alter the vas contraction. This review covers structure, receptors, neurotransmitters, smooth muscle physiology, and clinical implications of the vas deferens.
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Affiliation(s)
- David S Koslov
- Wake Forest Baptist Medical Center, Medical Center Boulevard Winston-Salem, NC, USA
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32
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Goyal RK, Chaudhury A. Structure activity relationship of synaptic and junctional neurotransmission. Auton Neurosci 2013; 176:11-31. [PMID: 23535140 PMCID: PMC3677731 DOI: 10.1016/j.autneu.2013.02.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2009] [Revised: 12/28/2012] [Accepted: 02/18/2013] [Indexed: 12/18/2022]
Abstract
Chemical neurotransmission may include transmission to local or remote sites. Locally, contact between 'bare' portions of the bulbous nerve terminal termed a varicosity and the effector cell may be in the form of either synapse or non-synaptic contact. Traditionally, all local transmissions between nerves and effector cells are considered synaptic in nature. This is particularly true for communication between neurons. However, communication between nerves and other effectors such as smooth muscles has been described as nonsynaptic or junctional in nature. Nonsynaptic neurotransmission is now also increasingly recognized in the CNS. This review focuses on the relationship between structure and function that orchestrate synaptic and junctional neurotransmissions. A synapse is a specialized focal contact between the presynaptic active zone capable of ultrafast release of soluble transmitters and the postsynaptic density that cluster ionotropic receptors. The presynaptic and the postsynaptic areas are separated by the 'closed' synaptic cavity. The physiological hallmark of the synapse is ultrafast postsynaptic potentials lasting milliseconds. In contrast, junctions are juxtapositions of nerve terminals and the effector cells without clear synaptic specializations and the junctional space is 'open' to the extracellular space. Based on the nature of the transmitters, postjunctional receptors and their separation from the release sites, the junctions can be divided into 'close' and 'wide' junctions. Functionally, the 'close' and the 'wide' junctions can be distinguished by postjunctional potentials lasting ~1s and tens of seconds, respectively. Both synaptic and junctional communications are common between neurons; however, junctional transmission is the rule at many neuro-non-neural effectors.
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Affiliation(s)
- Raj K Goyal
- Center for Swallowing and Motility Disorders, GI Division, VA Boston Healthcare System and Harvard Medical School, Boston, USA.
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Berg T, Jensen J. Tyramine Reveals Failing α2-Adrenoceptor Control of Catecholamine Release and Total Peripheral Vascular Resistance in Hypertensive Rats. Front Neurol 2013; 4:19. [PMID: 23450822 PMCID: PMC3584258 DOI: 10.3389/fneur.2013.00019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 02/11/2013] [Indexed: 11/13/2022] Open
Abstract
α2-Adrenoceptor-activation lowers central sympathetic output, peripheral, vesicular norepinephrine release, epinephrine secretion, and modulates vascular tension. We previously demonstrated that α2-adrenoceptor-mediated inhibition of basal norepinephrine release was not reflected in plasma unless re-uptake through the norepinephrine transporter (NET) was blocked. Tyramine activates reverse norepinephrine transport through NET. Here we tested the hypothesis that tyramine, by engaging NET in release, also blocks re-uptake, and therefore allows manipulation of pre-junctional α2-adrenoceptors to directly regulate norepinephrine overflow to plasma. We compared in anesthetized spontaneously hypertensive rats (SHRs) and normotensive controls (WKYs), the effect of α2-adrenoreceptor antagonist (L-659,066) and/or agonist (clonidine) on norepinephrine overflow and increase in total peripheral vascular resistance (TPR) evoked by tyramine-infusion (1.26 μmol/min/kg, 15 min) and epinephrine secretion activated by the surgical stress. TPR was computed as blood pressure divided by cardiac output, recorded as ascending aortic flow. Plasma catecholamine concentrations after tyramine were higher in SHRs than WKYs. Pre-treatment with L-659,066 increased the catecholamine concentrations in WKYs, but only if combined with clonidine in SHRs. Clonidine alone reduced tyramine-induced norepinephrine overflow in SHRs, and epinephrine in both strains. Tyramine-induced increase in TPR was not different after clonidine, eliminated after L-659,066 and L-659,066 + clonidine in WKYs, but only after L-659,066 + clonidine in SHRs. We conclude that tyramine-infusion does allow presynaptic regulation of vesicular release to be accurately assessed by measuring differences in plasma norepinephrine concentration. Our results indicate that presynaptic α2-adrenoceptor regulation of norepinephrine release from nerve vesicles and epinephrine secretion is dysfunctional in SHRs, but can be restored by clonidine.
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Affiliation(s)
- Torill Berg
- Department of Physiology, Institute of Basic Medical Sciences, University of Oslo Oslo, Norway
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Burnstock G. Discovery of purinergic signalling, the initial resistance and current explosion of interest. Br J Pharmacol 2012; 167:238-55. [PMID: 22537142 PMCID: PMC3481036 DOI: 10.1111/j.1476-5381.2012.02008.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 04/03/2012] [Accepted: 04/12/2012] [Indexed: 01/23/2023] Open
Abstract
There has been a remarkable growth of papers published about purinergic signalling via ATP since 1972. I am most grateful to the wonderful PhD students and postdoctoral fellows who have worked with me over the years to pursue the purinergic hypothesis despite early opposition and to the many outstanding scientists around the world who are currently extending the story. Recently, therapeutic approaches to pathological disorders include the development of selective P1 and P2 receptor subtype agonists and antagonists, as well as of inhibitors of extracellular ATP breakdown and of ATP transport enhancers and inhibitors. Medicinal chemists are starting to develop small molecule purinergic drugs that are orally bioavailable and stable in vivo.
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Affiliation(s)
- G Burnstock
- Autonomic Neuroscience Centre, Royal Free and University College Medical School, Rowland Hill Street, London, UK.
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35
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da Silva FH, Claudino MA, Báu FR, Rojas-Moscoso JA, Mónica FZ, De Nucci G, Antunes E. Vas deferens smooth muscle responses to the nitric oxide-independent soluble guanylate cyclase stimulator BAY 41-2272. Eur J Pharmacol 2012; 688:49-55. [PMID: 22634166 DOI: 10.1016/j.ejphar.2012.05.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 04/24/2012] [Accepted: 05/15/2012] [Indexed: 01/23/2023]
Abstract
The nitric oxide-cGMP signaling pathway modulates the ejaculatory functions. The nitric oxide (NO)-independent soluble guanylate cyclase haem-dependent stimulator BAY 41-2272 potently relaxes different types of smooth muscles. However, no study investigated its effects in vas deferens smooth muscle. Therefore, we designed experiments to evaluate the in vitro relaxing responses of vas deferens to BAY 41-2272. The effects of prolonged oral intake with BAY 41-2272 in vas deferens contractions of rats treated chronically with the NO synthase inhibitor N(ω)-nitro-L-arginine methyl ester (L-NAME) were also investigated. BAY 41-2272 (0.001-100 μM) produced concentration-dependent relaxations in the prostatic and epididymal portions of vas deferens, an effect markedly reduced by the soluble guanylate cyclase inhibitor ODQ (100 μM). BAY 41-2272 significantly increased cGMP levels that were fully prevented by ODQ. In separate protocols, rats received L-NAME (20mg/rat/day) concomitantly with BAY 41-2272 (10mg/kg/day, 4 weeks), after which vas deferens contractions to electrical-field stimulation and noradrenaline were achieved. Electrical-field stimulation (1-32 Hz) evoked frequency-dependent contractions that were significantly enhanced in L-NAME-treated rats. Co-treatment with BAY 41-2272 fully reversed the increased contractile responses in L-NAME group. Noradrenaline (0.01-100 μM)-induced contractions were also greater in L-NAME-treated rats, and that was normalized by BAY 41-2272. In conclusion, BAY 41-2272 potently relaxes in vitro rat vas deferens smooth muscle and elevates the cGMP levels in an ODQ-sensitive manner. Moreover, prolonged oral intake with BAY 41-2272 restores the enhanced contractile vas deferens activity in rats treated with L-NAME. NO-independent soluble guanylate cyclase stimulators may be an alternative treatment for premature ejaculation.
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Affiliation(s)
- Fábio H da Silva
- Department of Pharmacology, Faculty of Medical Sciences, University of Campinas (UNICAMP), Campinas, SP, Brazil
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36
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Kaczmarek-Hájek K, Lörinczi E, Hausmann R, Nicke A. Molecular and functional properties of P2X receptors--recent progress and persisting challenges. Purinergic Signal 2012; 8:375-417. [PMID: 22547202 PMCID: PMC3360091 DOI: 10.1007/s11302-012-9314-7] [Citation(s) in RCA: 147] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 10/18/2011] [Indexed: 12/16/2022] Open
Abstract
ATP-gated P2X receptors are trimeric ion channels that assemble as homo- or heteromers from seven cloned subunits. Transcripts and/or proteins of P2X subunits have been found in most, if not all, mammalian tissues and are being discovered in an increasing number of non-vertebrates. Both the first crystal structure of a P2X receptor and the generation of knockout (KO) mice for five of the seven cloned subtypes greatly advanced our understanding of their molecular and physiological function and their validation as drug targets. This review summarizes the current understanding of the structure and function of P2X receptors and gives an update on recent developments in the search for P2X subtype-selective ligands. It also provides an overview about the current knowledge of the regulation and modulation of P2X receptors on the cellular level and finally on their physiological roles as inferred from studies on KO mice.
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Affiliation(s)
- Karina Kaczmarek-Hájek
- Max Planck Institute for Experimental Medicine, Hermann Rein Str. 3, 37075, Göttingen, Germany
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37
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Lalo U, Verkhratsky A, Burnstock G, Pankratov Y. P2X receptor-mediated synaptic transmission. ACTA ACUST UNITED AC 2012. [DOI: 10.1002/wmts.28] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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38
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Macarthur H, Wilken GH, Westfall TC, Kolo LL. Neuronal and non-neuronal modulation of sympathetic neurovascular transmission. Acta Physiol (Oxf) 2011; 203:37-45. [PMID: 21362154 PMCID: PMC3139802 DOI: 10.1111/j.1748-1716.2010.02242.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Noradrenaline, neuropeptide Y and adenosine triphosphate are co-stored in, and co-released from, sympathetic nerves. Each transmitter modulates its own release as well as the release of one another; thus, anything affecting the release of one of these transmitters has consequences for all. Neurotransmission at the sympathetic neurovascular junction is also modulated by non-sympathetic mediators such as angiotensin II, serotonin, histamine, endothelin and prostaglandins through the activation of specific pre-junctional receptors. In addition, nitric oxide (NO) has been identified as a modulator of sympathetic neuronal activity, both as a physiological antagonist against the vasoconstrictor actions of the sympathetic neurotransmitters, and also by directly affecting transmitter release. Here, we review the modulation of sympathetic neurovascular transmission by neuronal and non-neuronal mediators with an emphasis on the actions of NO. The consequences for co-transmission are also discussed, particularly in light of hypertensive states where NO availability is diminished.
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Affiliation(s)
- H Macarthur
- Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, MO 63104, USA.
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39
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Lalo U, Verkhratsky A, Pankratov Y. Ionotropic ATP receptors in neuronal-glial communication. Semin Cell Dev Biol 2011; 22:220-8. [PMID: 21320623 DOI: 10.1016/j.semcdb.2011.02.012] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2010] [Revised: 01/05/2011] [Accepted: 02/07/2011] [Indexed: 01/10/2023]
Abstract
In the central nervous system ATP is released from both neurones and astroglial cells acting as a homo- and heterocellular neurotransmitter. Glial cells express numerous purinoceptors of both ionotropic (P2X) and metabotropic (P2Y) varieties. Astroglial P2X receptors can be activated by ongoing synaptic transmission and can mediate fast local signalling through elevation in cytoplasmic Ca(2+) and Na(+) concentrations. These ionic signals can be translated into various physiological messages by numerous pathways, including release of gliotransmitters, metabolic support of neurones and regulation of activity of postsynaptic glutamate and GABA receptors. Ionotropic purinoceptors represent a novel pathway of glia-driven modulation of synaptic signalling that involves the release of ATP from neurones and astrocytes followed by activation of P2X receptors which can regulate synaptic activity by variety of mechanisms expressed in both neuronal and glial compartments.
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Affiliation(s)
- Ulyana Lalo
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, UK
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40
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Burnstock G, Kennedy C. P2X receptors in health and disease. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2011; 61:333-372. [PMID: 21586364 DOI: 10.1016/b978-0-12-385526-8.00011-4] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Seven P2X receptor subunits have been cloned which form functional homo- and heterotrimers. These are cation-selective channels, equally permeable to Na(+) and K(+) and with significant Ca(2+) permeability. The three-dimensional structure of the P2X receptor is described. The channel pore is formed by the α-helical transmembrane spanning region 2 of each subunit. When ATP binds to a P2X receptor, the pore opens within milliseconds, allowing the cations to flow. P2X receptors are expressed on both central and peripheral neurons, where they are involved in neuromuscular and synaptic neurotransmission and neuromodulation. They are also expressed in most types of nonneuronal cells and mediate a wide range of actions, such as contraction of smooth muscle, secretion, and immunomodulation. Changes in the expression of P2X receptors have been characterized in many pathological conditions of the cardiovascular, gastrointestinal, respiratory, and urinogenital systems and in the brain and special senses. The therapeutic potential of P2X receptor agonists and antagonists is currently being investigated in a range of disorders, including chronic neuropathic and inflammatory pain, depression, cystic fibrosis, dry eye, irritable bowel syndrome, interstitial cystitis, dysfunctional urinary bladder, and cancer.
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Affiliation(s)
- G Burnstock
- Autonomic Neuroscience Centre, University College Medical School, London, United Kingdom
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White CW, Short JL, Haynes JM, Evans RJ, Ventura S. The residual nonadrenergic contractile response to nerve stimulation of the mouse prostate is mediated by acetylcholine but not ATP in a comparison with the mouse vas deferens. J Pharmacol Exp Ther 2010; 335:489-96. [PMID: 20724483 DOI: 10.1124/jpet.110.172130] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Neuronal release of noradrenaline is primarily responsible for the contraction of prostatic smooth muscle in all species, and this forms the basis for the use of α(1)-adrenoceptor antagonists as pharmacotherapies for benign prostatic hyperplasia. Previous studies in mice have demonstrated that a residual nonadrenergic component to nerve stimulation remains after α(1)-adrenoceptor antagonism. In the guinea pig and rat prostate and the vas deferens of guinea pigs, rats, and mice, ATP is the mediator of this residual contraction. This study investigates the mediator of residual contraction in the mouse prostate. Whole prostates from wild-type, α(1A)-adrenoceptor, and P2X1-purinoceptor knockout mice were mounted in organ baths, and the isometric force that tissues developed in response to electrical field stimulation or exogenously applied agonists was recorded. Deletion of the P2X1 purinoceptor did not affect nerve-mediated contraction. Furthermore, the P2-purinoceptor antagonist suramin (30 μM) failed to attenuate nerve-mediated contractions in wild-type, α(1A)-adrenoceptor, or P2X1-purinoceptor knockout mice. Atropine (1 μM) attenuated contraction in prostates taken from wild-type mice. In the presence of prazosin (0.3 μM) or guanethidine (10 μM), or in prostates taken from α(1A)-adrenoceptor knockout mice, residual nerve-mediated contraction was abolished by atropine (1 μM), but not suramin (30 μM). Exogenously administered acetylcholine elicited reproducible concentration-dependent contractions of the mouse prostate that were atropine-sensitive (1 μM), but not prazosin-sensitive (0.3 μM). Acetylcholine, but not ATP, mediates the nonadrenergic component of contraction in the mouse prostate. This cholinergic component of prostatic contraction is mediated by activation of muscarinic receptors.
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Affiliation(s)
- Carl W White
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
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42
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Patel BA, Arundell M, Parker KH, Yeoman MS, O'Hare D. Microelectrode investigation of neuroneal ageing from a single identified neurone. Phys Chem Chem Phys 2010; 12:10065-72. [PMID: 20625576 DOI: 10.1039/c0cp00310g] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Microelectrode amperometry is uniquely suited for characterising the dynamics of neurotransmitter release, as it offers unparalleled spatial and temporal resolution. We have used carbon fibre microelectrodes to study release of the monoamine neurotransmitter serotonin (5-HT) and the gaseous transmitter nitric oxide (NO) in intact central nervous system of the water snail, Lymnaea stagnalis. Analysis of spontaneous vesicular release of 5-HT and depolarisation-induced release of NO reveals significant differences with ageing that may be associated with changes in protein structure and function.
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Affiliation(s)
- Bhavik Anil Patel
- Department of Bioengineering, Imperial College London, London, SW7 2AZ, UK
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