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Abstract
PURPOSE OF REVIEW This review presents recent findings on the role of prostaglandins in migraine pathophysiology. RECENT FINDINGS Experimental studies have shown that prostaglandins are distributed in the trigeminal-vascular system and its receptors are localized in the trigeminal ganglion and the trigeminal nucleus caudalis. Prostaglandins were found in smooth muscles of cranial arteries, and functional studies in vivo showed that prostaglandins induced dilatation of cranial vessels. Human studies showed that intravenous infusion of vasodilating prostaglandins such as prostaglandin E₂ (PGE₂), prostaglandin I₂ (PGI₂) and prostaglandin D₂ (PGD₂) induced headache and dilatation of intra-cranial and extra-cranial arteries in healthy volunteers. In contrast, infusion of non-dilating prostaglandin F₂α (PGF₂α) caused no headache or any vascular responses in cranial arteries. PGE₂ and PGI₂ triggered migraine-like attacks in migraine patients without aura, accompanied by dilatation of the intra-cerebral and extra-cerebral arteries. A novel EP4 receptor antagonist could not prevent PGE₂-induced headache in healthy volunteers. SUMMARY Recent in-vitro/in-vivo data demonstrated presence and action of prostaglandins within the trigeminal pain pathways. Migraine induction after intravenous administration of PGE₂ and PGI₂ suggests a specific blockade of their receptors, EP and IP respectively, as a new potential drug target for the acute treatment of migraine.
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Antonova M, Wienecke T, Olesen J, Ashina M. Pro-inflammatory and vasoconstricting prostanoid PGF2α causes no headache in man. Cephalalgia 2011; 31:1532-41. [DOI: 10.1177/0333102411423314] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background: During two decades of migraine provocation studies with naturally occurring signalling molecules, vasodilators such as prostaglandin E2, prostaglandin I2 (prostacyclin) and prostaglandin D2 were shown to be able to induce headache in man. To elucidate the role of inflammation and vasodilatation in the generation of headache, we investigated whether the pro-inflammatory and vasoconstricting prostanoid prostaglandin F2α (PGF2α) would cause headache in a human model of headache. Methods: Twelve healthy volunteers were randomly allocated to receive 3.5 µg/kg/min PGF2α or placebo over 20 min in a two-way crossover study. We recorded headache intensity on a verbal rating scale, middle cerebral artery blood flow velocity (VMCA) and the diameters of the superficial temporal artery (STA) and radial artery (RA). Results: We found no difference in the area under the curve (AUC) for immediate headache (0–90 min) between PGF2α and placebo ( p = 0.144). The McNemar's test showed no difference in the incidence of immediate and delayed headache between verum and placebo ( p = 0.500 and p = 1.000, respectively). There was no difference in VMCA ( p = 0.776) and in the diameter of the STA ( p = 0.460) or RA ( p = 0.780) between PGF2α and placebo. Conclusion: The present study shows that PGF2α, unlike vasodilating prostaglandins, does not provoke headache. We suggest that the vasodilating abilities of prostaglandins are important for the induction of experimental headache in healthy volunteers.
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Ghorbani B, Holmstrup P, Edvinsson L, Kristiansen KA, Sheykhzade M. LPS from Porphyromonas gingivalis increases the sensitivity of contractile response mediated by endothelin-B (ET(B)) receptors in cultured endothelium-intact rat coronary arteries. Vascul Pharmacol 2010; 53:250-7. [PMID: 20888431 DOI: 10.1016/j.vph.2010.09.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 09/14/2010] [Accepted: 09/24/2010] [Indexed: 12/21/2022]
Abstract
The purpose of our study was to examine if lipopolysaccharide (LPS) from Porphyromonas gingivalis (P.g.) modifies the vasomotor responses to Endothelin-1 (ET-1) and Sarafotoxin 6c (S6c) in rat coronary arteries. The arteries were studied directly or following organ culture for 24 h in absence and presence of 2.5EU/ml LPS. The contractile responses of coronary arteries were investigated by using the selective ETB receptor agonist S6c (1 pM-0.3 μM) and ET-1 (1 pM-0.3 μM). The functional studies demonstrated an augmented contractile response only to S6c in isolated rat coronary arteries after organ culture (with or without LPS). These contractile responses by S6c were blocked by the selective ETB receptor antagonist BQ788 in both vessel groups. The augmented contractile response to S6c was supported by immunohistochemistry, where a significant increase in fluorescence intensity for ETB receptors in smooth muscle cells was observed after organ culture. The presence of LPS in the culture medium significantly increased the sensitivity of endothelium-intact coronary artery to S6c as compared to endothelium-denuded segments. Our results showed a significant increase in both ETB receptor protein levels and S6c-induced maximal contraction in coronary arteries upon 24 h of organ culture, which was further sensitized by LPS.
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Affiliation(s)
- Bahareh Ghorbani
- Department of Periodontology, School of Dentistry, University of Copenhagen, Denmark
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Ferrero E, Labalde M, Fernández N, Monge L, Salcedo A, Narvaez-Sanchez R, Hidalgo M, Dieguez G, García-Villalon AL. Response to endothelin-1 in arteries from human colorectal tumours: role of endothelin receptors. Exp Biol Med (Maywood) 2008; 233:1602-7. [PMID: 18849535 DOI: 10.3181/0802-rm-69] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
To examine the reaction of tumour arteries to endothelin-1, we obtained arteries supplying blood flow to colorectal tumours from patients, as well as mesenteric arteries supplying the normal colon tissue from the same patients and mesenteric arteries from patients without a colorectal tumour pathology. The contraction in response to endothelin-1 and the relaxation produced by bradykinin was recorded in each of these arteries. Accordingly, the sensitivity to endothelin-1 but not the maximal response, was higher in the arteries supplying colorectal tumours than in mesenteric arteries supplying normal colon or in mesenteric arteries from patients with no tumour pathology. The contraction produced by endothelin-1 was not modified by exposure to L-NAME or meclofenamate in arteries supplying both the tumour and the normal colon. The endothelin ET(A) andET(B) receptors were expressed similarly in arteries supplying the tumour or normal colon. However, the antagonist of the endothelin ET(B) receptors BQ788 (10(-6) M) decreased the contractions in the arteries supplying the tumour but not in those supplying the normal colon. By contrast, the antagonist of endothelin ET(A) receptors BQ123 (10(-6) M) reduced the contraction equally in both these types of arteries. Likewise, in arteries precontracted with U46619, the relaxation in response to bradykinin was similar in all three types of arteries. Together, these results suggest that the arteries supplying human colorectal tumours are more sensitive to endothelin-1, which could be due to the enhanced activity of endothelin ET(B) receptors in the absence of any change in the modulatory effect of nitric oxide or prostanoids in the arterial response to this peptide.
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Affiliation(s)
- Eduardo Ferrero
- Departamento de Cirugía General y Digestiva (Section B), Hospital Universitario 12 de Octubre, Universidad Complutense, Madrid, Spain
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Nilsson D, Wackenfors A, Gustafsson L, Ugander M, Ingemansson R, Edvinsson L, Malmsjö M. PKC and MAPK signalling pathways regulate vascular endothelin receptor expression. Eur J Pharmacol 2008; 580:190-200. [DOI: 10.1016/j.ejphar.2007.10.071] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2007] [Revised: 10/12/2007] [Accepted: 10/18/2007] [Indexed: 01/24/2023]
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Tummala S, Hill BJF. The enhanced endothelin-1-induced contraction in cultured coronary arteries from mature female pigs is not antagonized by 17beta-estradiol. Vascul Pharmacol 2006; 46:346-52. [PMID: 17240201 PMCID: PMC1924796 DOI: 10.1016/j.vph.2006.12.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2006] [Revised: 11/14/2006] [Accepted: 12/01/2006] [Indexed: 11/16/2022]
Abstract
We have previously reported that organ cultured coronary arteries from market-age pigs (6-9 months of age) exhibit an enhanced contraction to the atherosclerotic-associated peptide, endothelin-1 (ET-1). The objective of this study was to investigate the interaction of 17beta-estradiol with ET-1 in organ cultured coronary arteries from older female pigs (3-4 years old). A cumulative concentration-response relationship (1 x 10(-9) M to 3 x 10(-7) M) was generated to ET-1, and the isometric tension measured in fresh and organ cultured (4 days at 37 degrees C) arterial rings that were each pre-incubated for 50 min in different concentrations (1 x 10(-9) M to 1 x 10(-5) M) of 17beta-estradiol. Compared to freshly used arteries, culturing induced a 2-fold increase in tension development to ET-1 (3 x 10(-7) M). Although 17beta-estradiol previously relaxed pre-constricted (with a 60 mM KCl solution) arteries, it did not affect the constrictive response to ET-1. Also, using an ET-1 ELISA we found that 17beta-estradiol did not effect ET-1 production in intact arteries. Our results indicate that 17beta-estradiol does not attenuate the production and constrictive properties of ET-1 in coronary arteries demonstrating a dedifferentiated cell phenotype.
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Affiliation(s)
- Saigiridhar Tummala
- Department of Biology, University of Central Arkansas, 201 Donaghey Avenue, Conway, AR 72035, USA
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Granström BW, Xu CB, Nilsson E, Vikman P, Edvinsson L. Smoking particles enhance endothelin A and endothelin B receptor-mediated contractions by enhancing translation in rat bronchi. BMC Pulm Med 2006; 6:6. [PMID: 16539723 PMCID: PMC1448182 DOI: 10.1186/1471-2466-6-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2005] [Accepted: 03/15/2006] [Indexed: 12/11/2022] Open
Abstract
Background Smoking is known to cause chronic inflammatory changes in the bronchi and to contribute to airway hyper-reactivity, such as in bronchial asthma. To study the effect of smoking on the endothelin system in rat airways, bronchial segments were exposed to DMSO-soluble smoking particles (DSP) from cigarette smoke, to nicotine and to DMSO, respectively. Methods Isolated rat bronchial segments were cultured for 24 hours in the presence or absence of DSP, nicotine or DMSO alone. Contractile responses to sarafotoxin 6c (a selective agonist for ETB receptors) and endothelin-1 (an ETA and ETB receptor agonist) were studied by use of a sensitive myograph. Before ET-1 was introduced, the ETB receptors were desensitized by use of S6c. The remaining contractility observed was considered to be the result of selective activation of the ETA receptors. ETA and ETB receptor mRNA expression was analyzed using real-time quantitative PCR. The location and concentration of ETA and ETB receptors were studied by means of immunohistochemistry together with confocal microscopy after overnight incubation with selective antibodies. Results After being cultured together with DSP for 24 hours the bronchial segments showed an increased contractility mediated by ETA and ETB receptors, whereas culturing them together with nicotine did not affect their contractility. The up-regulation of their contractility was blunted by cycloheximide treatment, a translational inhibitor. No significant change in the expression of ETA and ETB receptor mRNA through exposure to DMSO or to nicotine exposure alone occurred, although immunohistochemistry revealed a clear increase in ETA and ETB receptors in the smooth muscle after incubation in the presence of DSP. Taken as a whole, this is seen as the presence of a translation mechanism. Conclusion The increased contractility of rat bronchi when exposed to DSP appears to be due to a translation mechanism.
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Affiliation(s)
- Bengt W Granström
- Department of Medicine, Clinical sciences, Lund, Lund University, Sweden
| | - Cang-Bao Xu
- Department of Medicine, Clinical sciences, Lund, Lund University, Sweden
| | - Elisabeth Nilsson
- Department of Medicine, Clinical sciences, Lund, Lund University, Sweden
| | - Petter Vikman
- Department of Medicine, Clinical sciences, Lund, Lund University, Sweden
| | - Lars Edvinsson
- Department of Medicine, Clinical sciences, Lund, Lund University, Sweden
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Uddman E, Henriksson M, Eskesen K, Edvinsson L. Role of mitogen-activated protein kinases in endothelin ETB receptor up-regulation after organ culture of rat mesenteric artery. Eur J Pharmacol 2004; 482:39-47. [PMID: 14660003 DOI: 10.1016/j.ejphar.2003.09.055] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Organ culture of isolated arteries results in increased levels of endothelin ET(B) (ET(B)) receptor mRNA and in enhanced ET(B) receptor mediated contraction. The present study was designed to pinpoint the mitogen-activated protein kinase (MAPK) subtype involved in up-regulation of ET(B) receptors after organ culture of rat mesenteric arteries. Western blot and selective antibodies towards constitutional and phosphorylated MAPKs revealed the appearance of phosphorylated MAPK of the extracellular signal-regulated kinases (ERK) 1/2 type at 3 h of organ culture. The functional ET(B) receptor and its mRNA expression were up-regulated after 24 h of organ culture. Following incubation with the MEK 1/2 specific inhibitor SB408039 or the raf inhibitor SB386023b the up-regulation was attenuated both for ET(B) receptor responses and in ET(B) receptor mRNA expression in the vessel segments. Neither Western blot nor myograph or mRNA analysis showed involvement of the other MAPKs studied. Our results suggest that the ERK1/2 MAPKs are involved in the endothelin ET(B) receptor up-regulation following organ culture.
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Affiliation(s)
- Erik Uddman
- Division of Experimental Vascular Research, Department of Internal Medicine, Lund University Hospital, Wallenberg Neurocentrum, BMC A13 Solvegatan 17, SE-221 85 Lund, Sweden.
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Granström BW, Xu CB, Nilsson E, Bengtsson UH, Edvinsson L. Up-Regulation of Endothelin Receptor Function and mRNA Expression in Airway Smooth Muscle Cells Following Sephadex-Induced Airway Inflammation. Basic Clin Pharmacol Toxicol 2004; 95:43-8. [PMID: 15245576 DOI: 10.1111/j.1742-7843.2004.pto950109.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The hypothesis that up-regulation of bronchial constrictor endothelin receptors in airway smooth muscle cells may contribute to hyperreactivity during airway inflammation was tested in the present study by quantitative endothelin receptor mRNA analysis and functional responses in ring segments of rat trachea and bronchi. Real time reverse transcription polymerase chain reaction was used to quantify endothelin receptor expression in rat airway smooth muscle cells following Sephadex-induced inflammation. Compared with controls, Sephadex-induced airway inflammation caused a significant increase (3.9 times P<0.05) of endothelin receptor type B mRNA expression in bronchial smooth muscle cells, but not in tracheal smooth muscle cells. Functional myograph studies of bronchial and tracheal ring segments without epithelium (mechanically denuded) revealed an increase of the maximum contractile effects of endothelin-1 (a dual agonist for both endothelin type A and B receptors) and sarafotoxin 6c (a selective agonist for endothelin B receptors) in bronchial smooth muscle cells in Sephadex-induced inflammation, but not in tracheal smooth muscle cells. The enhanced maximal responses of bronchial smooth muscle cells to endothelin-1 and sarafotoxin 6c in Sephadex-induced inflammation support our molecular findings and hence imply a role for endothelin B receptors in airway hyperreactivity during airway inflammation.
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Wackenfors A, Emilson M, Ingemansson R, Hortobagyi T, Szok D, Tajti J, Vecsei L, Edvinsson L, Malmsjö M. Ischemic heart disease induce upregulation of endothelin receptor mRNA in human coronary arteries. Eur J Pharmacol 2004; 484:103-9. [PMID: 14729387 DOI: 10.1016/j.ejphar.2003.11.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Endothelin has been implicated in the pathogenesis of ischemic heart disease and congestive heart failure. The aims were to quantify endothelin type A (ETA) and type B (ETB) receptor mRNA levels in human coronary arteries from patients with ischemic heart disease, congestive heart failure and controls using real-time polymerase chain reaction (real-time PCR). In addition, the suitability of organ culture as a model mimicking endothelin receptor changes in cardiovascular disease was evaluated by in vitro pharmacology and real-time PCR. Endothelin ETA and ETB receptor mRNA levels were significantly higher in arteries from patients with ischemic heart disease (0.23+/-0.04 and 0.35+/-0.06) as compared to congestive heart failure (0.09+/-0.02 and 0.07+/-0.01) and controls (0.08+/-0.02 and 0.08+/-0.01). After organ culture, the endothelin ETB receptor mRNA levels were elevated, and the sarafotoxin 6c-induced vasoconstriction was more efficacious. Increased endothelin receptor activity may contribute to the increased vascular tone and development of atherosclerotic disease in ischemic heart disease in man.
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Affiliation(s)
- Angelica Wackenfors
- Department of Internal Medicine, Division of Experimental Vascular Research, BMC A13, Lund University Hospital, SE-221 84, Lund, Sweden.
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Uddman E, Adner M, Edvinsson L. Protein kinase C inhibitors decrease endothelin ET(B) receptor mRNA expression and contraction during organ culture of rat mesenteric artery. Eur J Pharmacol 2002; 452:215-22. [PMID: 12354572 DOI: 10.1016/s0014-2999(02)02303-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The effect of protein kinase C (PKC) inhibitors on the induction of endothelin ET(B) receptors during organ culture was examined in isolated segments of the rat mesenteric artery. After 24 h of organ culture, the endothelin ET(B) receptor agonist sarafotoxin 6c (S6c) induced a strong contraction compared to fresh segments. The contractile response after 24-h organ culture to S6c was studied in presence (30-min preincubation) or absence, after 24-h treatment, of the PKC inhibitors staurosporine, K252a and Ro31-7549. Exposure to staurosporine or K252a in presence and after 24-h treatment reduced the S6c contraction. In contrast, presence of 2-1[1-3(aminopropyl)indol-3-yl]-3(1-methyl-1H-indol-3-yl)maleimide (Ro31-7549), did not affect the S6c-induced contraction, whereas 24-h treatment abolished the increase of contraction. The PKA inhibitor N-(2-[bromocinnamylamino]-ethyl)-5-isoquinolinesulfonamide (H89) did not affect the S6c responses. The mRNA expressions of endothelin ET(B) receptors (analysed with real-time PCR) were abolished after 24-h treatment with the PKC inhibitors. These results suggest that PKC is involved in the endothelin ET(B) receptor upregulation following organ culture.
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Affiliation(s)
- Erik Uddman
- Department of Internal Medicine, Lund University Hospital, Lund, Sweden.
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Stenman E, Malmsjö M, Uddman E, Gidö G, Wieloch T, Edvinsson L. Cerebral ischemia upregulates vascular endothelin ET(B) receptors in rat. Stroke 2002; 33:2311-6. [PMID: 12215604 DOI: 10.1161/01.str.0000028183.04277.32] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Elevated levels of endothelin-1 (ET-1) have been reported in cerebral ischemia. A role for ET may prove more important if the vascular receptors were changed. We addressed whether there is any change in ET receptor expression in cerebral ischemia. METHODS The right middle cerebral artery (MCA) was occluded in male Wistar rats for 2 hours with the intraluminal filament method. The basilar artery and both MCAs were removed after 46 hours of recirculation. The contractile responses to ET-1, a combined ET(A) and ET(B) receptor agonist, and sarafotoxin 6c (S6c), a selective ET(B) receptor agonist, were examined in vitro, and ET receptor mRNA was quantified by real-time polymerase chain reaction. RESULTS S6c, which had no contractile effect per se on fresh or sham-operated rat cerebral arteries, induced a marked contraction in the occluded MCA (E(max) [maximum contraction, calculated as percentage of the contractile capacity of 63.5 mmol/L K+]=68+/-68%; P<0.0001), while there was no difference in the responses to ET-1 after cerebral ischemia. Real-time polymerase chain reaction revealed a significant upregulation of both the ET(A) and ET(B) receptors (both P<0.05) in the occluded MCA compared with the nonoccluded MCA from the same rats. CONCLUSIONS Focal cerebral ischemia in rat induces increased transcription of both ET(A) and ET(B) receptors, which results in the appearance of a contractile response to the ET(B) receptor agonist S6c. These results suggest a role for ET receptors in the pathogenesis of a vascular component after cerebral ischemia.
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MESH Headings
- Animals
- Basilar Artery/drug effects
- Basilar Artery/physiopathology
- Brain Ischemia/etiology
- Brain Ischemia/physiopathology
- Disease Models, Animal
- Endothelin-1/pharmacology
- In Vitro Techniques
- Infarction, Middle Cerebral Artery/complications
- Infarction, Middle Cerebral Artery/physiopathology
- Male
- Middle Cerebral Artery/drug effects
- Middle Cerebral Artery/physiopathology
- Peptide Elongation Factor 1/genetics
- Peptide Elongation Factor 1/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Wistar
- Receptor, Endothelin A
- Receptor, Endothelin B
- Receptors, Endothelin/agonists
- Receptors, Endothelin/genetics
- Receptors, Endothelin/metabolism
- Up-Regulation
- Vasoconstriction/drug effects
- Vasoconstrictor Agents/pharmacology
- Viper Venoms/pharmacology
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Affiliation(s)
- Emelie Stenman
- Division of Experimental Vascular Research, Department of Internal Medicine, Lund University Hospital, Lund, Sweden.
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D'Orléans-Juste P, Labonté J, Bkaily G, Choufani S, Plante M, Honoré JC. Function of the endothelinB receptor in cardiovascular physiology and pathophysiology. Pharmacol Ther 2002; 95:221-38. [PMID: 12243796 DOI: 10.1016/s0163-7258(02)00235-8] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
One of the two receptors by which the potent vasoactive effects of endothelin (ET)-1 are mediated is the ET(B) receptor (ET(BR)), which is found in several tissues, but, more importantly from a cardiovascular point of view, on the endothelial cell. The endothelial cell also has the unique capability of releasing ET-1, as well as other factors, such as the endothelial-derived relaxing factors and prostacyclin, which counteract the myotropic effects of the peptide. The secretory and contractile responses to ET-1 rely on G-protein-coupled ET(BR)s, as well as ET(A)-G-protein-coupled receptor-like proteins. The mitogenic properties of ET-1 via ET(A) receptors (ET(AR)s) coupled to mitogen-activated protein kinases and tyrosine kinases on the vascular smooth muscle may occur in conjunction with the anti-apoptotic characteristics of the endothelial ET(BR)s. Interestingly, most of the relevant antagonists and agonists for both ET(AR)s and ET(BR)s have been developed by the pharmaceutical industry. This highlights the therapeutical potential of compounds that act on ET receptors. In normal as well as in physiopathological conditions, the ET(BR) plays an important role in the control of vascular tone, and must be taken into account when using ET receptor antagonists for the treatment of cardiovascular diseases. For the management of congestive heart failure, renal failure and primary pulmonary hypertension, the most recent literature supports the use of selective ET(AR) antagonists rather than mixed antagonists of ET(AR)s and ET(BR)s. Nonetheless, validation of this view will have to await the first clinical trials comparing the actions of ET(A) to mixed ET(A)/ET(B) receptor antagonists.
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Affiliation(s)
- P D'Orléans-Juste
- Department of Pharmacology, Institut de Pharmacologie de Sherbrooke, Medical School, Université de Sherbrooke, 3001 12th Avenue North, Sherbrooke, J1H 5N4, Québec, Canada.
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White LR, Juul R, Cappelen J, Aasly J. Cyclooxygenase inhibitors attenuate endothelin ET(B) receptor-mediated contraction in human temporal artery. Eur J Pharmacol 2002; 448:51-7. [PMID: 12126971 DOI: 10.1016/s0014-2999(02)01894-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
It is well documented that endothelin ET(B) receptor-mediated contraction develops in artery segments incubated in culture and that the reaction is augmented by proinflammatory cytokines, but little is known of the mechanisms involved. Segments of human temporal artery were incubated in organ culture for 2 days in the absence or presence of interleukin-1 beta (IL-1 beta), with or without nonsteroidal anti-inflammatory drugs, glucocorticoids or a nitric oxide synthase inhibitor. Thereafter, contractions were induced by the selective endothelin ET(B) receptor agonist, sarafotoxin S6c. Acetylsalicylic acid, indomethacin, nimesulide and rofecoxib were all effective in eliminating the increase in endothelin ET(B) receptor-mediated contraction induced by interleukin-1 beta, but only indomethacin and rofecoxib significantly reduced the spontaneous development of this reaction in cultured arteries. Dexamethasone and methylprednisolone augmented the reaction, and the nitric oxide synthase inhibitor had no effect. The results clearly indicate a role for cyclooxygenase, most likely cyclooxygenase-2, in endothelin ET(B) receptor-mediated contraction in this preparation.
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Affiliation(s)
- Linda R White
- Department of Neurology and Clinical Neurophysiology, University Hospital of Trondheim, N-7006 Trondheim, Norway.
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15
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White LR, Juul R, Skaanes KO, Aasly J. Cytokine enhancement of endothelin ET(B) receptor-mediated contraction in human temporal artery. Eur J Pharmacol 2000; 406:117-22. [PMID: 11011042 DOI: 10.1016/s0014-2999(00)00642-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Segments of human temporal artery were incubated in organ culture for 2 days in the absence or presence of cytokines. Thereafter, contractions were induced by the selective endothelin ET(B) receptor agonist sarafotoxin S6c, a peptide that does not induce contraction in fresh human temporal artery. Interleukin-1beta was most potent in increasing the sarafotoxin-induced contraction in cultured segments. Tumour necrosis factor (TNF)-alpha increased the magnitude of contraction to a similar degree, but at a higher dose. A significant increase was also induced by interferon-gamma, but not by interleukin-6 at the concentrations used. The results suggest that endothelin ET(B) receptor-mediated contraction can be enhanced by pro-inflammatory cytokines in a concentration-dependent manner, and this may have relevance for pathophysiological conditions where inflammation and vasoactivity are important.
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Affiliation(s)
- L R White
- Department of Neurology, Trondheim University Hospital, N-7006, Trondheim, Norway.
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