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Zhou L, Zhan W, Wei X. Clinical pharmacology and pharmacogenetics of prostaglandin analogues in glaucoma. Front Pharmacol 2022; 13:1015338. [PMID: 36313286 PMCID: PMC9596770 DOI: 10.3389/fphar.2022.1015338] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 09/29/2022] [Indexed: 07/30/2023] Open
Abstract
Glaucoma is the main cause of irreversible visual loss worldwide, and comprises a group of progressive, age-related, and chronic optic neuropathies. Prostaglandin analogs are considered a first-line treatment in the management of glaucoma and have the best efficacy in reducing intraocular pressure. When comparing these therapeutic agents between them, long-term therapy with 0.03% bimatoprost is the most effective followed by treatment with 0.005% latanoprost and 0.004% travoprost. The prevalence of adverse events is lower for latanoprost than for other prostaglandin analogs. However, some patients do not respond to the treatment with prostaglandin analogs (non-responders). Intraocular pressure-lowering efficacy differs significantly between individuals partly owing to genetic factors. Rs1045642 in ABCB1, rs4241366 in SLCO2A1, rs9503012 in GMDS, rs10306114 in PTGS1, rs11568658 in MRP4, rs10786455 and rs6686438 in PTGFR were reported to be positive with the response to prostaglandin analogs in patients with glaucoma. A negative association was found between single nucleotide polymorphisms of PTGFR (rs11578155 and rs6672484) and the response to prostaglandin analogs in patients with glaucoma. The current review is an analysis of the information relevant to prostaglandin analog treatments based on previous literatures. It describes in detail the clinical pharmacology and pharmacogenetics of drugs belonging to this therapeutical class to provide a sound pharmacological basis for their proper use in ophthalmological clinical practice.
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Affiliation(s)
- Lin Zhou
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Wenyi Zhan
- West China School of Medicine, Sichuan University, Chengdu, China
| | - Xin Wei
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
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Ernst C, Skov Jensen P, Aalkjaer C, Bek T. Differential Effects of Intra- and Extravascular ATP on the Diameter of Porcine Vessels at Different Branching Levels Ex Vivo. Invest Ophthalmol Vis Sci 2021; 61:8. [PMID: 33035289 PMCID: PMC7552936 DOI: 10.1167/iovs.61.12.8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Purpose Adenosine triphosphate (ATP) is involved in the diameter regulation of retinal vessels. The compound has been shown to induce both constriction and dilatation, but the detailed mechanisms underlying these effects and the site of action of the compound are not known in detail. Therefore, the purpose of the present study was to investigate whether the vasoactive effects of ATP on retinal vessels depend on intra- and extravascular application, and to study whether the effects differ at different vascular branching levels. Methods Diameter changes in arterioles, pre-capillary arterioles, and capillaries were studied in perfused porcine hemiretinas (n = 48) ex vivo after intra- and extravascular application of the nondegradable ATP analogue ATP-γ-S or ATP in the presence or not of antagonists to the CD73/ecto-5′-nucleotidase (AOPCP), the P2-purinergic receptor (PPADS), the A3-adenosine receptor (MRS1523), and the synthesis of cyclooxygenase products (ibuprofen). Results Intravascular ATP-induced constriction and extravascular ATP-induced dilatation of retinal arterioles, pre-capillary arterioles and capillaries, and dilatation was inhibited by ibuprofen. Both constriction and dilatation of arterioles were inhibited by antagonizing ATP degradation. Furthermore, constriction at all three branching levels was antagonized by blocking the A3 purinoceptor, whereas constriction in arterioles and pre-capillary arterioles was antagonized by blocking the P2 purinoceptor. Conclusions ATP affects the diameter of retinal arterioles, pre-capillary arterioles, and capillaries through different pathways, and the effects depend on whether the compound is administered intravascularly or extravascularly. This may form the basis for selective interventions on retinal vascular disease with differential involvement of vessels at different branching levels.
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Affiliation(s)
- Charlotte Ernst
- Department of Ophthalmology, Aarhus University Hospital, DK-8200 Aarhus N, Denmark
| | - Peter Skov Jensen
- Department of Ophthalmology, Aarhus University Hospital, DK-8200 Aarhus N, Denmark
| | - Christian Aalkjaer
- Department of Biomedicine (Physiology), University of Aarhus, DK-8000 Aarhus C, Denmark
| | - Toke Bek
- Department of Ophthalmology, Aarhus University Hospital, DK-8200 Aarhus N, Denmark
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Petersen L, Bek T. Post-hypoxic constriction of retinal arterioles is impaired during nitric oxide and cyclo-oxygenase inhibition and in diabetic patients without retinopathy. Graefes Arch Clin Exp Ophthalmol 2017; 255:1965-1971. [DOI: 10.1007/s00417-017-3746-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 05/23/2017] [Accepted: 07/05/2017] [Indexed: 01/14/2023] Open
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Barquissau V, Ghandour RA, Ailhaud G, Klingenspor M, Langin D, Amri EZ, Pisani DF. Control of adipogenesis by oxylipins, GPCRs and PPARs. Biochimie 2016; 136:3-11. [PMID: 28034718 DOI: 10.1016/j.biochi.2016.12.012] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 12/02/2016] [Accepted: 12/23/2016] [Indexed: 01/15/2023]
Abstract
Oxylipins are bioactive metabolites derived from the oxygenation of ω3 and ω6 polyunsaturated fatty acids, triggered essentially by cyclooxygenase and lipoxygenase activities. Oxylipins are involved in the development and function of adipose tissue and their productions are strictly related to diet quality and quantity. Oxylipins signal via cell surface membrane (G Protein-coupled receptors) and nuclear receptors (peroxisome proliferator-activated receptors), two pathways playing a pivotal role in adipocyte biology. In this review, we made an attempt to cover the available knowledge about synthesis and molecular function of oxylipins known to modulate adipogenesis, adipocyte function and phenotype conversion, with a focus on their interaction with peroxisome proliferator-activated nuclear receptor family.
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Affiliation(s)
- Valentin Barquissau
- Inserm, UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases, Toulouse, 31432, France; University of Toulouse, UMR1048, Paul Sabatier University, Toulouse, 31432, France
| | | | | | - Martin Klingenspor
- Technische Universität München, Chair of Molecular Nutritional Medicine, Else Kröner-Fresenius Center, 85350, Freising-Weihenstephan, Germany
| | - Dominique Langin
- Inserm, UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases, Toulouse, 31432, France; University of Toulouse, UMR1048, Paul Sabatier University, Toulouse, 31432, France; Toulouse University Hospitals, Department of Clinical Biochemistry, Toulouse, 31059, France
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Doucette LP, Walter MA. Prostaglandins in the eye: Function, expression, and roles in glaucoma. Ophthalmic Genet 2016; 38:108-116. [PMID: 27070211 DOI: 10.3109/13816810.2016.1164193] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Prostaglandins are small pro-inflammatory molecules derived from arachidonic acid that play roles in a multitude of biological processes including, but not limited to, inflammation, pain modulation, allergies, and bone formation. Prostaglandin analogues are the front-line medications for the treatment of glaucoma, a condition resulting in blindness due to the death of retinal ganglion cells. These drugs act by lowering intraocular pressure (IOP), a major risk factor for glaucoma. The currently used prostaglandin analogues (latanoprost, bimatoprost, tafluprost, and travoprost) mimic PGF2 and target one of the prostaglandin receptors (FP), though research into harnessing the other receptors using compounds like Sulprostone (EP3 receptor), or Iloprost (IP receptor) are currently ongoing. In this review, we summarize the research into each of the prostaglandin molecules (PGD2, PGE2, PGF2, PGI2, TXA2) and their respective receptors (DP, EP1, 2, 3, 4, FP, IP). We examine the modes of action of each of these receptors, their expression, their role in aqueous humour production and outflow within the eye, as well as their roles as medications for the treatment of glaucoma.
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Affiliation(s)
- Lance P Doucette
- a Department of Medical Genetics, Faculty of Medicine and Dentistry , University of Alberta , Edmonton , Alberta , Canada
| | - Michael A Walter
- a Department of Medical Genetics, Faculty of Medicine and Dentistry , University of Alberta , Edmonton , Alberta , Canada
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Kaya MY, Petersen L, Bek T. Lack of effect of nitroglycerin on the diameter response of larger retinal arterioles in normal persons during hypoxia. Graefes Arch Clin Exp Ophthalmol 2015; 254:277-83. [PMID: 26617179 DOI: 10.1007/s00417-015-3227-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 11/08/2015] [Accepted: 11/16/2015] [Indexed: 11/25/2022] Open
Abstract
PURPOSE Retinal hypoxia with consequent changes in blood flow play a role in a number of vision-threatening diseases, such as diabetic retinopathy. Previous studies have shown that the inhibition of nitric oxide synthase (NOS) and cyclooxygenase (COX) products are involved in the diameter regulation of the retinal vessels during hypoxia. Therefore, the aim of the present study was to examine the effects of an NO donor combined with COX inhibition on the diameter regulation of retinal vessels during hypoxia in normal persons. METHODS Twenty normal persons aged 21-47 years were examined. The Dynamic Vessel Analyzer (DVA) was used to measure retinal vessel diameters at rest, during isometric exercise, and during flicker stimulation. The measurements were performed during normoxia and hypoxia before and after sublingual administration of the NO donor nitroglycerin, and were repeated on a second study day after topical administration of the COX-inhibitor diclofenac. RESULTS The resting diameter of arterioles and venules increased significantly during hypoxia (p < 0.0001). Hypoxia also significantly reduced the arteriolar constriction during isometric exercise, and the dilatation of the arterioles and venules during flicker stimulation (p < 0.0001). Diclofenac further reduced the arteriolar constriction induced by isometric exercise during hypoxia (p = 0.005). However, the NO-donor nitroglycerin had no effect on vascular diameters. CONCLUSION Diameter regulation of retinal vessels during hypoxia in normal persons can be influenced by the inhibition of COX products, but not by increasing the NO concentration. The findings suggest that the vasoactive effects of NO on retinal arterioles during hypoxia are saturated in normal persons.
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Affiliation(s)
- Musa Yasin Kaya
- Department of Ophthalmology, Aarhus University Hospital, DK-8000, Aarhus C, Denmark.
| | - Line Petersen
- Department of Ophthalmology, Aarhus University Hospital, DK-8000, Aarhus C, Denmark
| | - Toke Bek
- Department of Ophthalmology, Aarhus University Hospital, DK-8000, Aarhus C, Denmark
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Riis-Vestergaard MJ, Bek T. Purinergic mechanisms and prostaglandin E receptors involved in ATP-induced relaxation of porcine retinal arterioles in vitro. Ophthalmic Res 2015; 54:135-42. [PMID: 26376245 DOI: 10.1159/000438905] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 07/22/2015] [Indexed: 11/19/2022]
Abstract
PURPOSE Adenosine triphosphate (ATP) is involved in the tone regulation of retinal arterioles, and the effect may be direct, through ATP degradation or mediated by cyclo-oxygenase products. However, the relative contribution of these mechanisms and the extent to which the mechanisms are active in the retinal vascular wall or depend on the perivascular retinal tissue are unknown. METHODS Porcine retinal arterioles with perivascular retinal tissue were mounted in a wire myograph for isometric tone recordings. The relaxing effects of ATP and the non-degradable analogue ATP-x03B3;S were studied in the presence of antagonists to ATP, adenosine and prostaglandin E (EP) receptors. The experiments were repeated after removal of the perivascular retinal tissue. RESULTS ATP induced a significant concentration-dependent relaxation of retinal arterioles (p < 0.05) which was reduced after removal of perivascular retinal tissue. The effect was due to non-degraded ATP and a degradation product of ATP acting via adenosine receptors. Relaxation was reduced by ibuprofen and blocking of EP1 receptors. CONCLUSION ATP-induced relaxation of retinal arterioles is mediated by ATP, ATP degradation products and by stimulation of EP1 receptors, involving both the perivascular retina and the vascular wall. The findings emphasize the complexity of purinergic effects in the regulation of retinal vascular tone.
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Kremmer S, Iliadou M, Anastassiou G, Schallenberg M, Vilser W, Steuhl KP, Selbach JM. Influence of latanoprost on retinal microcirculation in glaucoma. Open Ophthalmol J 2014; 8:60-6. [PMID: 25317217 PMCID: PMC4195175 DOI: 10.2174/1874364101408010060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 07/21/2014] [Accepted: 07/21/2014] [Indexed: 11/22/2022] Open
Abstract
Purpose : To test whether latanoprost has an influence on ocular haemodynamics, considering the general reputation of prostaglandins which is frequently associated with vasoconstriction. The effect of latanoprost on the retinal blood supply of treatment-naïve glaucoma patients was tested. Materials and Methodology : 13 patients (7 male, 6 female) who had just recently been diagnosed with primary open-angle glaucoma (POAG) were treated with latanoprost (0.005%). The average age of our study group was 63.8 years (+/- 2.9 years). The drug’s effect on retinal autoregulation was assessed by flicker test using the Dynamic Vessel Analyzer (DVA). Examinations took place before initializing treatment, after 4 weeks and once again after 4 to 6 months. Results : In our group of POAG patients, the IOP under treatment was significantly reduced about 25%. No intraindividual differences in systemic blood pressure and heart rate were observed. In DVA measurements of glaucoma patients, the maximum flicker dilation of the arteries was significantly lower than reported for healthy volunteers. Beyond that, POAG patients did not show significant differences in vessel diameters, peak amplitudes as well as maximum dilations of retinal arteries and veins before and under treatment with latanoprost (0.005%). Conclusion : Latanoprost markedly lowered the IOP but it did not exert a significant effect on retinal haemodynamics. There was neither a tendency towards vasoconstriction nor towards vasodilation. Sustaining reperfusion damage after topical latanoprost therapy thus seems to be highly unlikely. Further studies must show if sole IOP lowering or a dual positive effect – IOP lowering and improvement of retinal vessel autoregulation – have a more positive impact on the long term follow-up of glaucoma patients.
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Affiliation(s)
- S Kremmer
- Department of Ophthalmology, Evangelische Kliniken Gelsenkirchen, Munckelstr. 27, 45879 Gelsenkirchen, Germany ; Department of Ophthalmology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - M Iliadou
- Department of Ophthalmology, Evangelische Kliniken Gelsenkirchen, Munckelstr. 27, 45879 Gelsenkirchen, Germany
| | - G Anastassiou
- Department of Ophthalmology, Evangelische Kliniken Gelsenkirchen, Munckelstr. 27, 45879 Gelsenkirchen, Germany ; Department of Ophthalmology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - M Schallenberg
- Department of Ophthalmology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - W Vilser
- Institute of Biomedical Engineering and Informatics, Ilmenau University of Technology, Ilmenau, Gustav-Kirchhoff-Str.2, Germany ; Imedos Systems UG, Jena, Am Naßtal 4, Germany
| | - K P Steuhl
- Department of Ophthalmology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
| | - J M Selbach
- Department of Ophthalmology, Evangelische Kliniken Gelsenkirchen, Munckelstr. 27, 45879 Gelsenkirchen, Germany ; Department of Ophthalmology, University of Duisburg-Essen, Hufelandstr. 55, 45122 Essen, Germany
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Pisani DF, Ghandour RA, Beranger GE, Le Faouder P, Chambard JC, Giroud M, Vegiopoulos A, Djedaini M, Bertrand-Michel J, Tauc M, Herzig S, Langin D, Ailhaud G, Duranton C, Amri EZ. The ω6-fatty acid, arachidonic acid, regulates the conversion of white to brite adipocyte through a prostaglandin/calcium mediated pathway. Mol Metab 2014; 3:834-47. [PMID: 25506549 PMCID: PMC4264041 DOI: 10.1016/j.molmet.2014.09.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 09/03/2014] [Accepted: 09/04/2014] [Indexed: 12/01/2022] Open
Abstract
Objective Brite adipocytes are inducible energy-dissipating cells expressing UCP1 which appear within white adipose tissue of healthy adult individuals. Recruitment of these cells represents a potential strategy to fight obesity and associated diseases. Methods/Results Using human Multipotent Adipose-Derived Stem cells, able to convert into brite adipocytes, we show that arachidonic acid strongly inhibits brite adipocyte formation via a cyclooxygenase pathway leading to secretion of PGE2 and PGF2α. Both prostaglandins induce an oscillatory Ca++ signaling coupled to ERK pathway and trigger a decrease in UCP1 expression and in oxygen consumption without altering mitochondriogenesis. In mice fed a standard diet supplemented with ω6 arachidonic acid, PGF2α and PGE2 amounts are increased in subcutaneous white adipose tissue and associated with a decrease in the recruitment of brite adipocytes. Conclusion Our results suggest that dietary excess of ω6 polyunsaturated fatty acids present in Western diets, may also favor obesity by preventing the “browning” process to take place.
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Affiliation(s)
- Didier F Pisani
- Univ. Nice Sophia Antipolis, iBV, UMR 7277, 06100 Nice, France ; CNRS, iBV, UMR 7277, 06100 Nice, France ; Inserm, iBV, U1091, 06100 Nice, France
| | - Rayane A Ghandour
- Univ. Nice Sophia Antipolis, iBV, UMR 7277, 06100 Nice, France ; CNRS, iBV, UMR 7277, 06100 Nice, France ; Inserm, iBV, U1091, 06100 Nice, France
| | - Guillaume E Beranger
- Univ. Nice Sophia Antipolis, iBV, UMR 7277, 06100 Nice, France ; CNRS, iBV, UMR 7277, 06100 Nice, France ; Inserm, iBV, U1091, 06100 Nice, France
| | - Pauline Le Faouder
- Lipidomic Core Facility, Metatoul Platform, France ; INSERM, UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases, Toulouse, France ; University of Toulouse, UMR1048, Paul Sabatier University, Toulouse, France
| | - Jean-Claude Chambard
- Univ. Nice Sophia Antipolis, iBV, UMR 7277, 06100 Nice, France ; CNRS, iBV, UMR 7277, 06100 Nice, France ; Inserm, iBV, U1091, 06100 Nice, France
| | - Maude Giroud
- Univ. Nice Sophia Antipolis, iBV, UMR 7277, 06100 Nice, France ; CNRS, iBV, UMR 7277, 06100 Nice, France ; Inserm, iBV, U1091, 06100 Nice, France
| | - Alexandros Vegiopoulos
- Joint Division Molecular Metabolic Control, Alliance and Network Aging Research, German Cancer Research Center (DKFZ), Center for Molecular Biology (ZMBH) and University Hospital, Heidelberg University, Heidelberg, Germany
| | - Mansour Djedaini
- Univ. Nice Sophia Antipolis, iBV, UMR 7277, 06100 Nice, France ; CNRS, iBV, UMR 7277, 06100 Nice, France ; Inserm, iBV, U1091, 06100 Nice, France
| | - Justine Bertrand-Michel
- Lipidomic Core Facility, Metatoul Platform, France ; INSERM, UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases, Toulouse, France ; University of Toulouse, UMR1048, Paul Sabatier University, Toulouse, France
| | - Michel Tauc
- Univ. Nice Sophia Antipolis, LP2M, UMR 7370, 06100 Nice, France ; UMR 7370, CNRS-LP2M, 06100 Nice, France
| | - Stephan Herzig
- Joint Division Molecular Metabolic Control, Alliance and Network Aging Research, German Cancer Research Center (DKFZ), Center for Molecular Biology (ZMBH) and University Hospital, Heidelberg University, Heidelberg, Germany
| | - Dominique Langin
- INSERM, UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases, Toulouse, France ; University of Toulouse, UMR1048, Paul Sabatier University, Toulouse, France ; Toulouse University Hospitals, Department of Clinical Biochemistry, Toulouse, France
| | - Gérard Ailhaud
- Univ. Nice Sophia Antipolis, iBV, UMR 7277, 06100 Nice, France ; CNRS, iBV, UMR 7277, 06100 Nice, France ; Inserm, iBV, U1091, 06100 Nice, France
| | - Christophe Duranton
- Univ. Nice Sophia Antipolis, LP2M, UMR 7370, 06100 Nice, France ; UMR 7370, CNRS-LP2M, 06100 Nice, France
| | - Ez-Zoubir Amri
- Univ. Nice Sophia Antipolis, iBV, UMR 7277, 06100 Nice, France ; CNRS, iBV, UMR 7277, 06100 Nice, France ; Inserm, iBV, U1091, 06100 Nice, France
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Petersen L, Bek T. Diameter changes of retinal arterioles during acute hypoxia in vivo are modified by the inhibition of nitric oxide and prostaglandin synthesis. Curr Eye Res 2014; 40:737-43. [PMID: 25198069 DOI: 10.3109/02713683.2014.954676] [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: 11/13/2022]
Abstract
PURPOSE Inhibition of cyclooxygenase (COX) and nitric oxide synthesis (NOS) has previously been shown to modify hypoxia-induced relaxation of retinal arterioles in vitro. The purpose of the present study was to investigate whether these findings can be reproduced in vivo. METHODS Twenty healthy persons aged 20-55 years were examined. Using the dynamic vessels analyzer (DVA), the resting diameter and diameter changes during isometric exercise and flicker stimulation were studied before and during breathing of a hypoxic gas mixture. The examinations were carried out before and during intravenous infusion of the NOS-inhibitor l-NMMA, and were repeated on a second study day after topical administration of the COX-inhibitor diclofenac. RESULTS The resting diameter of retinal arterioles increased significantly during hypoxia and decreased significantly during l-NMMA infusion (p < 0.0001) which compensated for changes in the blood pressure. During hypoxia and l-NMMA infusion together contraction of retinal arterioles could not compensate for the increased blood pressure as assessed by a gain factor significantly lower than one (p = 0.002). The arteriolar contraction induced by isometric exercise was significantly reduced by diclofenac and flicker-induced dilatation of retinal arterioles was increased during l-NMMA infusion (p < 0.0001). CONCLUSION Diameter changes of retinal vessels during acute hypoxia in vivo are modified by inhibiting NO and prostaglandin synthesis. The evidence points to possible new targets of intervention on the diameter regulation of retinal arterioles in diseases where retinal hypoxia is part of the disease pathogenesis.
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Affiliation(s)
- Line Petersen
- Department of Ophthalmology, Aarhus University Hospital , Aarhus C, Aarhus , Denmark
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Kida T, Sawada K, Kobayashi K, Hori M, Ozaki H, Murata T. Diverse effects of prostaglandin E₂ on vascular contractility. Heart Vessels 2013; 29:390-5. [PMID: 23748433 DOI: 10.1007/s00380-013-0374-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Accepted: 05/24/2013] [Indexed: 11/28/2022]
Abstract
Prostaglandin E₂ (PGE₂) is a major prostanoid produced under inflammatory situations. There have been controversial reports showing contractile or relaxant effect of PGE₂ on vascular tone in various types of blood vessels. Thus, it is still elusive whether and how PGE₂ modulates vascular tone. We here assessed the effects of PGE₂ on vascular contractility using different types of vasculatures isolated form rat. In endothelium-denuded aortas and mesenteric arteries, PGE₂ (1 nM-10 μM) concentration-dependently enhanced the contraction elicited by K(+) (35.4 mM) or norepinephrine (10 nM). In pulmonary arteries, PGE₂ did not alter the both-induced contraction. Tail arteries were relaxed by a low dose of PGE₂ (1-100 nM), but this response shifted to contraction by the higher dose of PGE₂ (300 nM-10 μM). There are four types of PGE₂ receptors EP1-4. RT-PCR showed that aortas and mesenteric arteries abundantly expressed EP3, while tail arteries abundantly expressed EP4. We next revealed that selective EP3 agonism enhanced the contraction in mesenteric arteries, whereas EP4 agonism induced relaxation in tail arteries. Taken together, PGE₂ causes different contractile responses depending on the type of vascular bed. This phenomenon may be due to the difference in expression pattern and activity of EP receptors.
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Affiliation(s)
- Taiki Kida
- Department of Veterinary Pharmacology and Animal Radiology, Graduate School of Agriculture and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
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