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Oka F, Chung DY, Suzuki M, Ayata C. Delayed Cerebral Ischemia After Subarachnoid Hemorrhage: Experimental-Clinical Disconnect and the Unmet Need. Neurocrit Care 2020; 32:238-251. [PMID: 30671784 PMCID: PMC7387950 DOI: 10.1007/s12028-018-0650-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND Delayed cerebral ischemia (DCI) is among the most dreaded complications following aneurysmal subarachnoid hemorrhage (SAH). Despite advances in neurocritical care, DCI remains a significant cause of morbidity and mortality, prolonged intensive care unit and hospital stay, and high healthcare costs. Large artery vasospasm has classically been thought to lead to DCI. However, recent failure of clinical trials targeting vasospasm to improve outcomes has underscored the disconnect between large artery vasospasm and DCI. Therefore, interest has shifted onto other potential mechanisms such as microvascular dysfunction and spreading depolarizations. Animal models can be instrumental in dissecting pathophysiology, but clinical relevance can be difficult to establish. METHODS Here, we performed a systematic review of the literature on animal models of SAH, focusing specifically on DCI and neurological deficits. RESULTS We find that dog, rabbit and rodent models do not consistently lead to DCI, although some degree of delayed vascular dysfunction is common. Primate models reliably recapitulate delayed neurological deficits and ischemic brain injury; however, ethical issues and cost limit their translational utility. CONCLUSIONS To facilitate translation, clinically relevant animal models that reproduce the pathophysiology and cardinal features of DCI after SAH are urgently needed.
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Affiliation(s)
- Fumiaki Oka
- Neurovascular Research Lab, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA.
- Department of Neurosurgery, Yamaguchi University School of Medicine, 1-1-1, Minami-Kogushi, Ube, Yamaguchi, 755-8505, Japan.
| | - David Y Chung
- Neurovascular Research Lab, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
- Stroke Service and Neuroscience Intensive Care Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
| | - Michiyasu Suzuki
- Department of Neurosurgery, Yamaguchi University School of Medicine, 1-1-1, Minami-Kogushi, Ube, Yamaguchi, 755-8505, Japan
| | - Cenk Ayata
- Neurovascular Research Lab, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
- Stroke Service and Neuroscience Intensive Care Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, USA
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Effect of endothelin receptor antagonists on clinically relevant outcomes after experimental subarachnoid hemorrhage: a systematic review and meta-analysis. J Cereb Blood Flow Metab 2015; 35:1085-9. [PMID: 25944590 PMCID: PMC4640283 DOI: 10.1038/jcbfm.2015.89] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 04/01/2015] [Accepted: 04/01/2015] [Indexed: 01/31/2023]
Abstract
In clinical trials, endothelin receptor antagonists (ETRAs) reduced vasospasm but did not improve functional outcome after subarachnoid hemorrhage (SAH). We assessed the effects of treatment with ETRAs on clinically relevant outcomes in animal studies modelling SAH by performing a systematic review of the literature for controlled animal studies of ETRAs for the treatment of SAH. Primary outcomes were neurobehavioral outcomes and case fatality. Secondary outcomes were cerebral vasospasm and cerebral blood flow. Summary estimates were calculated using normalized mean difference random effects meta-analysis. We included 27 studies (55 experiments, 639 animals). Neurobehavioral scores were reported in none of the experiments, and case fatality in 8 (15%). Treatment with ETRAs was associated with a pooled odds ratio for case fatality of 0.61 (95% confidence interval (CI), 0.27 to 1.39); a 54% increase (95% CI, 39 to 69) in cerebral arterial diameter; and a 93% increase (95% CI, 58 to 129) in cerebral blood flow. We conclude that there is no evidence from animal studies that treatment with an ETRA improves clinically relevant outcomes after SAH. The reduction in cerebral vasospasm observed in animal studies is consistent with that observed in clinical trials, an effect that is not associated with better functional outcome in patients.
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Yeung PKK, Shen J, Chung SSM, Chung SK. Targeted over-expression of endothelin-1 in astrocytes leads to more severe brain damage and vasospasm after subarachnoid hemorrhage. BMC Neurosci 2013; 14:131. [PMID: 24156724 PMCID: PMC3815232 DOI: 10.1186/1471-2202-14-131] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 10/15/2013] [Indexed: 01/15/2023] Open
Abstract
Background Endothelin-1 (ET-1) is a potent vasoconstrictor, and astrocytic ET-1 is reported to play a role in the pathogenesis of cerebral ischemic injury and cytotoxic edema. However, it is still unknown whether astrocytic ET-1 also contributes to vasogenic edema and vasospasm during subarachnoid hemorrhage (SAH). In the present study, transgenic mice with astrocytic endothelin-1 over-expression (GET-1 mice) were used to investigate the pathophysiological role of ET-1 in SAH pathogenesis. Results The GET-1 mice experienced a higher mortality rate and significantly more severe neurological deficits, blood–brain barrier breakdown and vasogenic edema compared to the non-transgenic (Ntg) mice following SAH. Oral administration of vasopressin V1a receptor antagonist, SR 49059, significantly reduced the cerebral water content in the GET-1 mice. Furthermore, the GET-1 mice showed significantly more pronounced middle cerebral arterial (MCA) constriction after SAH. Immunocytochemical analysis showed that the calcium-activated potassium channels and the phospho-eNOS were significantly downregulated, whereas PKC-α expression was significantly upregulated in the MCA of the GET-1 mice when compared to Ntg mice after SAH. Administration of ABT-627 (ETA receptor antagonist) significantly down-regulated PKC-α expression in the MCA of the GET-1 mice following SAH. Conclusions The present study suggests that astrocytic ET-1 involves in SAH-induced cerebral injury, edema and vasospasm, through ETA receptor and PKC-mediated potassium channel dysfunction. Administration of ABT-627 (ETA receptor antagonist) and SR 49059 (vasopressin V1a receptor antagonist) resulted in amelioration of edema and vasospasm in mice following SAH. These data provide a strong rationale to investigate SR 49059 and ABT-627 as therapeutic drugs for the treatment of SAH patients.
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Affiliation(s)
| | | | | | - Sookja K Chung
- Department of Anatomy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China.
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Zoerle T, Ilodigwe DC, Wan H, Lakovic K, Sabri M, Ai J, Macdonald RL. Pharmacologic reduction of angiographic vasospasm in experimental subarachnoid hemorrhage: systematic review and meta-analysis. J Cereb Blood Flow Metab 2012; 32:1645-58. [PMID: 22534672 PMCID: PMC3437599 DOI: 10.1038/jcbfm.2012.57] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Animal models have been developed to simulate angiographic vasospasm secondary to subarachnoid hemorrhage (SAH) and to test pharmacologic treatments. Our aim was to evaluate the effect of pharmacologic treatments that have been tested in humans and in preclinical studies to determine if animal models inform results reported in humans. A systematic review and meta-analysis of SAH studies was performed. We investigated predictors of translation from animals to humans with multivariate logistic regression. Pharmacologic reduction of vasospasm was effective in mice, rats, rabbits, dogs, nonhuman primates (standard mean difference of -1.74; 95% confidence interval -2.04 to -1.44) and humans. Animal studies were generally of poor methodologic quality and there was evidence of publication bias. Subgroup analysis by drug and species showed that statins, tissue plasminogen activator, erythropoietin, endothelin receptor antagonists, calcium channel antagonists, fasudil, and tirilazad were effective whereas magnesium was not. Only evaluation of vasospasm >3 days after SAH was independently associated with successful translation. We conclude that reduction of vasospasm is effective in animals and humans and that evaluation of vasospasm >3 days after SAH may be preferable for preclinical models.
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Affiliation(s)
- Tommaso Zoerle
- Division of Neurosurgery, St Michael's Hospital, Labatt Family Centre of Excellence in Brain Injury and Trauma Research, Keenan Research Centre of the Li Ka Shing Knowledge Institute of St Michael's Hospital, Ontario, Canada
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Lin CL, Winardi W, Jeng AY, Kwan AL. Endothelin-converting enzyme inhibitors for the treatment of subarachnoid hemorrhage-induced vasospasm. Neurol Res 2007; 28:721-9. [PMID: 17164035 DOI: 10.1179/016164106x152007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
A burgeoning body of evidence suggests that endothelin-1 (ET-1), the most potent endogenous vasoconstrictor yet identified, may be critical in the pathophysiology of various cardiovascular diseases. The ET system may also be implicated in the pathogenesis of cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH). Clinical studies have shown that the levels of ET-1 are increased in the cerebrospinal fluid (CSF) of patients following SAH, suggesting that ET-1-mediated vasoconstriction plays a major role in the development of vasospasm after SAH. The potential involvement of ETs in SAH-induced vasospasm has triggered considerable interest in developing therapeutic strategies that inhibit the biologic effects of ET. One promising approach to block the biosynthesis of ETs is suppressing the proteolytic conversion of the precursor peptide (big ET-1) to its vasoactive form (ET-1) using metalloprotease as endothelin-converting enzyme (ECE) inhibitor. To date, three types of ECE-1 inhibitors have been synthesized: dual ECE-1/neutral endopeptidase 24.11 (NEP) inhibitors, triple ECE-1/NEP/angiotensin-converting enzyme (ACE) inhibitors and selective ECE-1 inhibitors. The therapeutic effects of ECE-1 inhibitors on the prevention and reversal of SAH-induced vasospasm in animal studies are reviewed and discussed.
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Affiliation(s)
- Chih-Lung Lin
- Department of Neurosurgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan, Republic of China
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Narushima I, Kita T, Kubo K, Yonetani Y, Momochi C, Yoshikawa I, Ohno N, Nakashima T. Highly enhanced permeability of blood-brain barrier induced by repeated administration of endothelin-1 in dogs and rats. PHARMACOLOGY & TOXICOLOGY 2003; 92:21-6. [PMID: 12710593 DOI: 10.1034/j.1600-0773.2003.920104.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The effects of intracisternal administration of endothelin-1 on blood-brain barrier permeability were examined in dogs and rats. Single doses of endothelin-1 elevated blood-brain barrier permeability about two times compared with control groups in both species. However, repeated dosing with endothelin-1 at a 24 hr intervals caused a highly enhanced disruption of blood-brain barrier permeability in dogs, but not in rats, whereas the repeated administration with a 48 hr interval markedly increased the blood-brain barrier permeability in both species of animals (dogs: 923%, rats: more than 661%). Moreover, this abnormally enhanced permeability of blood-brain barrier in dogs was completely blocked by pretreatment with the endothelin ET-A receptor selective antagonist, S-0139, administered prior to either the first or second dosing with endothelin-1. From these results, we conclude that a repeated attack of endothelin-1 from the adventitial site of brain blood vessels produces a severe disruption of blood-brain barrier permeability through an endothelin ET-A receptor-mediated process.
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Affiliation(s)
- Itaru Narushima
- Department of Pharmacology, Nara Medical University, 840 Shijo-cho, Kashihara, Nara, 634-8521, Japan
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Chow M, Dumont AS, Kassell NF. Endothelin Receptor Antagonists and Cerebral Vasospasm: An Update. Neurosurgery 2002. [DOI: 10.1227/01.neu.0000309108.94215.71] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Michael Chow
- Department of Neurosurgery, University of Virginia, Charlottesville, Virginia
| | - Aaron S. Dumont
- Department of Neurosurgery, University of Virginia, Charlottesville, Virginia
| | - Neal F. Kassell
- Department of Neurosurgery, University of Virginia, Charlottesville, Virginia
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Remuzzi G, Perico N, Benigni A. New therapeutics that antagonize endothelin: promises and frustrations. Nat Rev Drug Discov 2002; 1:986-1001. [PMID: 12461520 DOI: 10.1038/nrd962] [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: 01/08/2023]
Abstract
The discovery of endothelin--a highly potent endogenous vasoconstrictor - in 1988 has led to considerable efforts to develop antagonists of endothelin receptors that could have therapeutic potential in disorders including hypertension, heart failure and renal diseases. However, in general, the results of trials in humans have not mirrored the highly promising effects in animal disease models. Here, we discuss preclinical and clinical results with endothelin antagonists, and consider possible approaches to fully realizing the potential of endothelin antagonism.
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Affiliation(s)
- Giuseppe Remuzzi
- Mario Negri Institute for Pharmacological Research, Via Gavazzeni 11, 24125 Bergamo, Italy.
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Tran Dinh YR, Jomaa A, Callebert J, Reynier-Rebuffel AM, Tedgui A, Savarit A, Sercombe R. Overexpression of cyclooxygenase-2 in rabbit basilar artery endothelial cells after subarachnoid hemorrhage. Neurosurgery 2001; 48:626-33; discussion 633-5. [PMID: 11270554 DOI: 10.1097/00006123-200103000-00037] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE We investigated the expression in rabbit basilar arteries of cyclooxygenase (COX)-2, which is the inducible isoform of the enzyme of prostaglandin (PG) production, and the concentrations of the proinflammatory cytokine tumor necrosis factor alpha (TNFalpha) and representative PGs in the cerebrospinal fluid (CSF) after experimental subarachnoid hemorrhage (SAH). METHODS Seven sets of basilar arteries were removed from control rabbits and from rabbits killed 1 and 3 days after induced SAH. The arteries were subjected to identical simultaneous immunolabeling for examination with a confocal microscope. One-half of each artery was stained for the constitutive form COX-1 and the other half for COX-2. CSF was sampled in control animals and at 6 hours, 1 day, and 3 days for assays of TNFalpha, PGE2, and 6-keto-PGF1 (metabolite of PGI2). RESULTS COX-1 immunoreactivity in the endothelial layer was similar in the three groups. Weak endothelial COX-2 immunoreactivity was found in arteries of control animals. COX-2 staining was higher in the group killed at 3 days compared with the control group (P < 0.05). The levels of PGE2 and 6-keto-PGF1alpha in the CSF peaked significantly at 6 hours, then decreased at 3 days to the basal level (PGE2) or significantly lower (6-keto-PGF1). TNFalpha was undetectable in control CSF, significantly higher (P < 0.001) at 6 hours, and undetectable at 3 days. CONCLUSION After SAH, endothelial COX-1 immunoreactivity does not change, whereas overexpression of COX-2 occurs at 3 days. This induction does not seem linked to TNFalpha production, nor is it responsible for early raised levels of PGE2 and PGI2 in the CSF. We suggest that the role of induced COX-2 may be to modify gene expression and hence alter the properties of the vessel wall after SAH.
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Affiliation(s)
- Y R Tran Dinh
- Centre National de la Recherche Scientifique UPR 646, IFR6, Université Paris 7, France.
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Iwasaki T, Hayasaki-Kajiwara Y, Shimamura T, Naya N, Nakajima M. Endothelin receptor subtype antagonist activity of S-0139 in various isolated rabbit and canine arteries. Eur J Pharmacol 2000; 400:255-62. [PMID: 10988342 DOI: 10.1016/s0014-2999(00)00417-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Vascular responses to endothelin peptides have been proposed to be mainly mediated via subtypes of the endothelin receptor, endothelin ET(A1), endothelin ET(B1), and endothelin ET(B2). The antagonist activity of 27-O-3-[2-(3-carboxy-acryloylamino)-5-hydroxyphenyl]acryloyloxy myricerone, sodium salt (S-0139) at these endothelin receptor subtypes was evaluated using isolated rabbit femoral, pulmonary, and mesenteric arteries. S-0139 competitively antagonized the endothelin-1-induced contraction mediated by the endothelin ET(A1) receptor in endothelium-denuded rabbit femoral arteries with a pA(2) value of 8.6+/-0.1. Endothelin ET(B2) receptor-mediated contraction induced by sarafotoxin S6c in endothelium-denuded rabbit pulmonary arteries was also inhibited by S-0139 with a pA(2) value of 5.6+/-0. 1. The pA(2) value of S-0139 for the endothelin ET(B1) receptor, evaluated from the endothelin-3-induced relaxant response in endothelium-intact rabbit mesenteric arteries, was 6.2+/-0.2. In isolated canine basilar, coronary, mesenteric and renal arteries, endothelin-1 caused concentration-dependent contractions with EC(50) values of 0.49+/-0.07, 0.61+/-0.25, 0.92+/-0.21 and 1.18+/-0.24 nM, respectively. S-0139 antagonized the endothelin-1-induced contraction in these arteries with pA(2) values of 8.0+/-0.1, 7. 6+/-0.2, 7.6+/-0.2 and 7.6+/-0.1, respectively. These results suggest that S-0139 is a potent and selective endothelin ET(A1) receptor antagonist, and that the contractions induced by endothelin-1 in canine basilar, coronary, mesenteric and renal arteries are mediated mainly via the endothelin ET(A1) receptor subtype.
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MESH Headings
- Animals
- Arteries/drug effects
- Arteries/physiology
- Caffeic Acids/pharmacology
- Dogs
- Dose-Response Relationship, Drug
- Drug Interactions
- Endothelin Receptor Antagonists
- Endothelin-1/pharmacology
- Endothelin-3/pharmacology
- Endothelium, Vascular/physiology
- In Vitro Techniques
- Isometric Contraction/drug effects
- Male
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Oleanolic Acid/analogs & derivatives
- Oleanolic Acid/pharmacology
- Rabbits
- Receptor, Endothelin A
- Receptor, Endothelin B
- Receptors, Endothelin/classification
- Receptors, Endothelin/physiology
- Vasoconstrictor Agents/pharmacology
- Viper Venoms/pharmacology
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Affiliation(s)
- T Iwasaki
- Discovery Research Laboratories, Shionogi and Co., Ltd., 3-1-1 Futaba-cho, Toyonaka, 561-0825, Osaka, Japan
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Abstract
A high percentage of the population has aneurysms of the cerebral vessels, which are detected only by chance or after spontaneous rupture. Subarachnoid haemorrhage is still a problem because of high morbidity and mortality. Many patients do not fully recover neurologically and suffer from physical and psychosocial symptoms. The aims of treatment are to prevent the patient from rebleeding and to prevent secondary neurological damage. Whereas in former times, clipping of the aneurysm was often delayed for days or weeks, early operative intervention is the rule today, if the patient is not moribund and if there is no significant cerebral oedema. The anaesthetist can support the neurosurgeon with a spectrum of different methods of anaesthesia and monitoring, individually tailored to the needs of the patient. Most important, however, is a stable haemodynamic status, stable and normal intracranial pressure and a sufficient cerebral perfusion pressure. Vasospasm is still the main problem, as is early rebleeding. To treat this, nimodipine is the drug of choice combined with volume therapy, a slightly elevated cardiac output and a modestly elevated blood pressure.
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Affiliation(s)
- J F Zander
- Department of Anaesthesia, Städtische Kliniken Dortmund, Dortmund, Germany.
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Shimada K, Yonetani Y, Kita T, Suzumura A, Takayanagi T, Nakashima T. Cyclooxygenase 2 expression by endothelin-1-stimulated mouse resident peritoneal macrophages in vitro. Eur J Pharmacol 1998; 356:73-80. [PMID: 9761426 DOI: 10.1016/s0014-2999(98)00495-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Macrophages have been shown to produce endothelin and to play a role in the pathogenesis of neural damage after cerebral ischemia or vasospasm after subarachnoid hemorrhage. Cyclooxygenase 2 is induced during inflammation following brain insult and participates in inflammation-mediated neurotoxicity. However, it has not yet been established how endothelin-1 acts on cyclooxygenase 2 expression in macrophages. In the present study, we examined the effects of endothelin-1 on cyclooxygenase 2 expression and prostaglandin E2 production, and the effects of endothelin ET(A) and ET(B) receptor antagonists. Stimulation by endothelin-1 ranging from 10(-11) to 10(-9) M time and dose dependently increased the production of prostaglandin E2 and the expression of cyclooxygenase 2 protein without changing that of cyclooxygenase 1 protein, an effect which was inhibited by dexamethasone, nonsteroidal anti-inflammatory drugs and the selective endothelin ET(B) receptor antagonist, BQ788 (N-cis-2,6-dimethylpiperidinocarbonyl-L-gamma-methyl-leucyl-D-L-me thoxycarbonyl-tryptophanyl-D-norleucine). The selective endothelin ET(A) receptor antagonist, BQ123 [cyclo (D-Trp-D-Asp-Pro-D-Val-Leu)] also inhibited these reactions, but its potency was less than that of the selective endothelin ET(B) receptor antagonist. Endothelin ET(A) and ET(B) receptor antagonists had no effects on cyclooxygenase 2 protein expression and prostaglandin E2 production in lipopolysaccharide-stimulated macrophages. We conclude that endothelin-1 increases cyclooxygenase 2 protein expression and prostaglandin E2 production via mainly endothelin ET(B) receptors and partly endothelin ET(A) receptors in macrophages; however, lipopolysaccharide increases both cyclooxygenase 2 protein expression and prostaglandin E2 production in pacrophages without involving endothelin ET(A) or ET(B) receptor-mediated processes.
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Affiliation(s)
- K Shimada
- Department of Pharmacology, Nara Medical University, Kashihara, Japan.
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