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Zheng Q, Li N, Zhang Y, Li J, Zhang E, Xu Z. Fat-Diets in Perinatal Stages Altered Nr3c2-Mediated Ca 2+ Currents in Mesenteric Arteries of Offspring Rats. Mol Nutr Food Res 2023; 67:e2200722. [PMID: 37366318 DOI: 10.1002/mnfr.202200722] [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: 10/23/2022] [Revised: 04/12/2023] [Indexed: 06/28/2023]
Abstract
SCOPE Perinatal high-fat diets (PHF) can influence fetal/neonate development, resulting in cardiovascular pathogenesis, but precise mechanisms remain unclear. This study tests aldosterone receptor-mediated Ca2+ influx and the underlying mechanisms influenced by PHF. METHODS AND RESULTS Maternal S.D. rats receive PHF during pregnancy and lactation periods. Their male offspring are fed normal diets after weaning for four months. Mesenteric arteries (MA) are for electrophysiological testing, Ca2+ imaging, target gene expression, and promotor methylation. PHF increases aldosterone receptor gene Nr3c2-mediated Ca2+ currents in the smooth muscle cells (SMCs) of the MA via L-type Ca2+ channels (LTCC) in the offspring. The increased expression of aldosterone-receptors and LTCC are responsible for an activated Nr3c2-LTCC pathway in the vasculature, eventually predisposes an increase of Ca2+ influx in the myocytes of resistance arteries. The inhibitor of aldosterone-receptors suppresses the increased Ca2+ currents in the SMCs. Nr3c2 and LTCC are upregulated through the transcriptional mechanism in methylation, which can be reversed in the functional changes by methylation inhibitor 5AZA. CONCLUSION The results firstly demonstrate that aldosterone-receptor activation can stimulate Ca2+ currents via LTCC in vascular myocytes, which can be altered by perinatal foods via epigenetic changes of DNA methylation in the promoters of Nr3c2 and LTCC.
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Affiliation(s)
- Qiutong Zheng
- Maternal and Child Health Care Hospital of Wuxi & First Hospital of Soochow University, Jiangsu, 215000, China
| | - Na Li
- Maternal and Child Health Care Hospital of Wuxi & First Hospital of Soochow University, Jiangsu, 215000, China
| | - Yingying Zhang
- Maternal and Child Health Care Hospital of Wuxi & First Hospital of Soochow University, Jiangsu, 215000, China
| | - Jingyang Li
- Maternal and Child Health Care Hospital of Wuxi & First Hospital of Soochow University, Jiangsu, 215000, China
| | - Eryun Zhang
- Maternal and Child Health Care Hospital of Wuxi & First Hospital of Soochow University, Jiangsu, 215000, China
| | - Zhice Xu
- Maternal and Child Health Care Hospital of Wuxi & First Hospital of Soochow University, Jiangsu, 215000, China
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Zhuang XL, Zhu ZL, Huang QH, Yan FR, Zheng SY, Lai SM, Jiao HX, Lin MJ. High magnesium mitigates the vasoconstriction mediated by different types of calcium influx from monocrotaline-induced pulmonary hypertensive rats. Exp Physiol 2022; 107:359-373. [PMID: 35193162 DOI: 10.1113/ep090029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 02/07/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? The aim was to examine and explore the involvement of Mg2+ in mitigating the vasoconstriction in PAs and sPAs in the MCT-PAH rat model. What are the main finding and its importance? 1.Both SOCE- and ROCE-mediated vasoconstriction enhanced in the MCT-PAH model. 2.High magnesium inhibited vasoconstriction due to directly antagonizing Ca2+ and increasing NO release. 3.The inhibition effect of high magnesium was more notable in sPA. ABSTRACT Increased extracellular magnesium concentration ([Mg2+ ]e ) has been evidenced to attenuate the endothelin-1 (ET-1)-induced contractile response via the release of nitric oxide (NO) from the endothelium in proximal pulmonary arteries (PAs) of chronic hypoxic (CH) mice. Here we further examined the involvement of Mg2+ in the inhibition of vasoconstriction in PAs and distal smaller pulmonary arteries (sPAs) in a monocrotaline-induced pulmonary arterial hypertension (MCT-PAH) rat model. The data showed that in control rats, vasoconstriction in sPAs is more intense than that in PAs. In MCT-PAH rats, the store-operated Ca2+ entry (SOCE)-, and receptor-operated Ca2+ entry (ROCE)-mediated contraction was significantly strengthened. However, there was no upregulation of the vasoconstriction mediated by voltage-dependent calcium entry (VDCE). Furthermore, high magnesium greatly inhibited the VDCE-mediated contraction in PAs instead of sPAs, which was opposite to the ROCE-mediated contraction. Moreover, MCT pretreatment partly eliminated the endothelium-dependent vasodilation in PAs, which in sPAs, however, was still promoted by magnesium due to the increased NO release in pulmonary microvascular endothelial cells (PMVECs). In conclusion, the findings suggest that both SOCE- and ROCE-mediated vasoconstriction in the MCT-PAH model are enhanced, especially in sPAs. The inhibition effect of high magnesium on vasoconstriction can be achieved partly by its direct role as a Ca2+ antagonist and partly by increasing the NO release in PMVECs. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Xiao-Ling Zhuang
- Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Provinece, People's Republic of China.,Department of Pathology, Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian Provinece, PR China
| | - Zhuang-Li Zhu
- Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Provinece, People's Republic of China
| | - Qiu-Hong Huang
- Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Provinece, People's Republic of China.,School of Basic Medicine, Quanzhou Medical College, Quanzhou, Fujian Provinece, PR China
| | - Fu-Rong Yan
- Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Provinece, People's Republic of China.,Center for Molecular Diagnosis and Therapy, Respiratory Medicine Center of Fujian Provinece, Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian, PR China
| | - Si-Yi Zheng
- Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Provinece, People's Republic of China
| | - Su-Mei Lai
- Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Provinece, People's Republic of China
| | - Hai-Xia Jiao
- Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Provinece, People's Republic of China
| | - Mo-Jun Lin
- Key Laboratory of Fujian Province Universities on Ion Channel and Signal Transduction in Cardiovascular Diseases, Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Provinece, People's Republic of China
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Rincón R, Hernández A, Orozco C. In vitro effect of endothelin-1 and nifedipine on pulmonary vascular contraction of pulmonary hypertensive and non-pulmonary hypertensive chickens. JOURNAL OF APPLIED ANIMAL RESEARCH 2016. [DOI: 10.1080/09712119.2015.1125355] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Rocío Rincón
- Facultad de Medicina Veterinaria y de Zootecnia, Universidad Nacional de Colombia, Sede Bogotá, Colombia
| | - Aureliano Hernández
- Facultad de Medicina Veterinaria y de Zootecnia, Universidad Nacional de Colombia, Sede Bogotá, Colombia
| | - Camilo Orozco
- Facultad de Medicina Veterinaria y de Zootecnia, Universidad Nacional de Colombia, Sede Bogotá, Colombia
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Xu YJ, Elimban V, Dhalla NS. Reduction of blood pressure by store-operated calcium channel blockers. J Cell Mol Med 2015; 19:2763-70. [PMID: 26471725 PMCID: PMC4687696 DOI: 10.1111/jcmm.12684] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Accepted: 08/14/2015] [Indexed: 12/16/2022] Open
Abstract
The voltage-operated Ca(2+) channels (VOCC), which allow Ca(2+) influx from the extracellular space, are inhibited by anti-hypertensive agents such as verapamil and nifedipine. The Ca(2+) entering from outside into the cell triggers Ca(2+) release from the sarcoplasmic reticulum (SR) stores. To refill the depleted Ca(2+) stores in the SR, another type of Ca(2+) channels in the cell membrane, known as store-operated Ca(2+) channels (SOCC), are activated. These SOCCs are verapamil and nifedipine resistant, but are SKF 96465 (SK) and gadolinium (Gd(3+) ) sensitive. Both SK and Gd(3+) have been shown to reduce [Ca(2+) ]i in the smooth muscle, but their effects on blood pressure have not been reported. Our results demonstrated that both SK and Gd(3+) produced a dose-dependent reduction in blood pressure in rat. The combination of SK and verapamil produced an additive action in lowering the blood pressure. Furthermore, SK, but not Gd(3+) suppressed proliferation of vascular smooth muscle cells in the absence or presence of lysophosphatidic acid (LPA). SK decreased the elevation of [Ca(2+) ]i induced by LPA, endothelin-1 (ET-1) and angiotensin II (Ang II), but did not affect the norepinephrine (NE)-evoked increase in [Ca(2+) ]i . On the other hand, Gd(3+) inhibited the LPA and Ang II induced change in [Ca(2+) ]i , but had no effect on the ET-1 and NE induced increase in [Ca(2+) ]i . The combination of verapamil and SK abolished the LPA- or adenosine-5'-triphosphate (ATP)-induced [Ca(2+) ]i augmentation. These results suggest that SOCC inhibitors, like VOCC blocker, may serve as promising drugs for the treatment of hypertension.
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Affiliation(s)
- Yan-Jun Xu
- Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, Department of Physiology and Pathophysiology, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Vijayan Elimban
- Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, Department of Physiology and Pathophysiology, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Naranjan S Dhalla
- Institute of Cardiovascular Sciences, St. Boniface Hospital Research Centre, Department of Physiology and Pathophysiology, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
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5
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Mamo YA, Angus JA, Ziogas J, Soeding PF, Wright CE. The role of voltage-operated and non-voltage-operated calcium channels in endothelin-induced vasoconstriction of rat cerebral arteries. Eur J Pharmacol 2014; 742:65-73. [PMID: 25218985 DOI: 10.1016/j.ejphar.2014.09.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 08/29/2014] [Accepted: 09/01/2014] [Indexed: 11/30/2022]
Abstract
Endothelin-1 has been identified as a potential mediator in the pathogenesis of ischaemic stroke and cerebral vasospasm. The aim of this study was to analyse the role of voltage-operated calcium channels (VOCC) and non-VOCC in endothelin-1 induced vasoconstriction of rat cerebral arteries. Arterial segments were dissected from different regions of the cerebral circulation and responses assessed using wire myography. Endothelin-1 concentration-contraction curves were constructed in calcium-free medium or in the presence of nifedipine, NNC 55-0396 ((1S,2S)-2-(2-(N-[(3-benzimidazol-2-yl)propyl]-N-methylamino)ethyl)-6-fluoro-1,2,3,4-tetrahydro-1-isopropyl-2-naphtyl cyclopropanecarboxylate dihydrochloride) or SK&F 96365 (1-(2-(3-(4-methoxyphenyl)propoxy)-4-methoxyphenylethyl)-1H-imidazole) to inhibit the l-type VOCC, T-type VOCC and non-VOCC, respectively. Inhibition of the calcium channels or removal of calcium from the medium variably decreased the maximum effects (Emax) of endothelin-1, however its potency (pEC50) was unaltered. Endothelin-1 caused a small contraction (<22%) in calcium-free solution. Pre-treatment with nifedipine (1µM) did not affect responses to low concentrations of endothelin-1 but decreased Emax, while NNC 55-0396 (1µM) and SK&F 96365 (30-100µM) generally attenuated the endothelin-1-induced contraction. Combination of nifedipine with SK&F 96365 further decreased the Emax. The relaxant effect of the calcium channel antagonists was also assessed in pre-contracted arteries. Only nifedipine and SK&F 96365 relaxed the arteries pre-contracted with endothelin-1. In conclusion, VOCC and non-VOCC calcium channels are involved in different phases of the endothelin-1 contraction in rat cerebral vessels. T-type VOCC may be involved in contraction induced by low concentrations of endothelin-1, while l-type VOCC mediate the maintenance phase of contraction. VOCC and non-VOCC may work in concert in mediating contraction induced by endothelin-1.
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Affiliation(s)
- Yohannes A Mamo
- 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.
| | - James Ziogas
- Cardiovascular Therapeutics Unit, Department of Pharmacology and Therapeutics, University of Melbourne, Victoria 3010, Australia.
| | - Paul F Soeding
- 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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The NO/ONOO-cycle as the central cause of heart failure. Int J Mol Sci 2013; 14:22274-330. [PMID: 24232452 PMCID: PMC3856065 DOI: 10.3390/ijms141122274] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2013] [Revised: 10/23/2013] [Accepted: 10/24/2013] [Indexed: 01/08/2023] Open
Abstract
The NO/ONOO-cycle is a primarily local, biochemical vicious cycle mechanism, centered on elevated peroxynitrite and oxidative stress, but also involving 10 additional elements: NF-κB, inflammatory cytokines, iNOS, nitric oxide (NO), superoxide, mitochondrial dysfunction (lowered energy charge, ATP), NMDA activity, intracellular Ca(2+), TRP receptors and tetrahydrobiopterin depletion. All 12 of these elements have causal roles in heart failure (HF) and each is linked through a total of 87 studies to specific correlates of HF. Two apparent causal factors of HF, RhoA and endothelin-1, each act as tissue-limited cycle elements. Nineteen stressors that initiate cases of HF, each act to raise multiple cycle elements, potentially initiating the cycle in this way. Different types of HF, left vs. right ventricular HF, with or without arrhythmia, etc., may differ from one another in the regions of the myocardium most impacted by the cycle. None of the elements of the cycle or the mechanisms linking them are original, but they collectively produce the robust nature of the NO/ONOO-cycle which creates a major challenge for treatment of HF or other proposed NO/ONOO-cycle diseases. Elevated peroxynitrite/NO ratio and consequent oxidative stress are essential to both HF and the NO/ONOO-cycle.
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Andrade D, Serra R, Svensjö E, Lima APC, Ramos ES, Fortes FS, Morandini ACF, Morandi V, Soeiro MDN, Tanowitz HB, Scharfstein J. Trypanosoma cruzi invades host cells through the activation of endothelin and bradykinin receptors: a converging pathway leading to chagasic vasculopathy. Br J Pharmacol 2012; 165:1333-47. [PMID: 21797847 DOI: 10.1111/j.1476-5381.2011.01609.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE Independent studies in experimental models of Trypanosoma cruzi appointed different roles for endothelin-1 (ET-1) and bradykinin (BK) in the immunopathogenesis of Chagas disease. Here, we addressed the hypothesis that pathogenic outcome is influenced by functional interplay between endothelin receptors (ET(A)R and ET(B)R) and bradykinin B(2) receptors (B(2)R). EXPERIMENTAL APPROACH Intravital microscopy was used to determine whether ETR/B(2)R drives the accumulation of rhodamine-labelled leucocytes in the hamster cheek pouch (HCP). Inflammatory oedema was measured in the infected BALB/c paw of mice. Parasite invasion was assessed in CHO over-expressing ETRs, mouse cardiomyocytes, endothelium (human umbilical vein endothelial cells) or smooth muscle cells (HSMCs), in the presence/absence of antagonists of B(2)R (HOE-140), ET(A)R (BQ-123) and ET(B)R (BQ-788), specific IgG antibodies to each GPCRs; cholesterol or calcium-depleting drugs. RNA interference (ET(A)R or ET(B)R genes) in parasite infectivity was investigated in HSMCs. KEY RESULTS BQ-123, BQ-788 and HOE-140 reduced leucocyte accumulation in HCP topically exposed to trypomastigotes and blocked inflammatory oedema in infected mice. Acting synergistically, ET(A)R and ET(B)R antagonists reduced parasite invasion of HSMCs to the same extent as HOE-140. Exogenous ET-1 potentiated T. cruzi uptake by HSMCs via ETRs/B(2)R, whereas RNA interference of ET(A)R and ET(B)R genes conversely reduced parasite internalization. ETRs/B(2)R-driven infection in HSMCs was reduced in HSMC pretreated with methyl-β-cyclodextrin, a cholesterol-depleting drug, or in thapsigargin- or verapamil-treated target cells. CONCLUSIONS AND IMPLICATIONS Our findings suggest that plasma leakage, a neutrophil-driven inflammatory response evoked by trypomastigotes via the kinin/endothelin pathways, may offer a window of opportunity for enhanced parasite invasion of cardiovascular cells.
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Affiliation(s)
- Daniele Andrade
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Brazil
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Kawanabe Y, Takahashi M, Jin X, Abdul-Majeed S, Nauli AM, Sari Y, Nauli SM. Cilostazol prevents endothelin-induced smooth muscle constriction and proliferation. PLoS One 2012; 7:e44476. [PMID: 22957074 PMCID: PMC3434142 DOI: 10.1371/journal.pone.0044476] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Accepted: 08/08/2012] [Indexed: 01/15/2023] Open
Abstract
Cilostazol is a phosphodiesterase inhibitor that has been shown to inhibit platelet activation. Endothelin is known to be the most potent endogenous growth promoting and vasoactive peptide. In patients and animal models with stroke, the level of circulating endothelin increases and complicates the recovery progress contributed by vascular constriction (an immediate pathology) and vascular proliferation (a long-term pathology). However, the effects of cilostazol on endothelin have not been explored. To demonstrate the dual-antagonizing effects of cilostazol on vasoconstriction and cell proliferation induced by endothelin, we used primary culture of mouse vascular smooth muscle cells in vitro, mouse femoral artery ex vivo, and intracranial basilar artery ex vivo. We show that the dual-inhibition effects of cilostazol are mediated by blocking endothelin-induced extracellular calcium influx. Although cilostazol does not inhibit endothelin-induced intraorganellar calcium release, blockade of extracellular calcium influx is sufficient to blunt endothelin-induced vasoconstriction. We also show that cilostazol inhibits endothelin-induced cellular proliferation by blocking extracellular calcium influx. Inhibition of cAMP-dependent protein kinase (PKA) can block anti-proliferation activity of cilostazol, confirming the downstream role of PKA in cellular proliferation. To further demonstrate the selectivity of the dual-antagonizing effects of cilostazol, we used a different phosphodiesterase inhibitor. Interestingly, sildenafil inhibits endothelin-induced vasoconstriction but not cellular proliferation in smooth muscle cells. For the first time, we show selective dual-antagonizing effects of cilostazol on endothelin. We propose that cilostazol is an excellent candidate to treat endothelin-associated diseases, such as stroke.
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Affiliation(s)
- Yoshifumi Kawanabe
- Department of Pharmacology, The University of Toledo, Toledo, Ohio, United States of America
| | - Maki Takahashi
- Department of Pharmacology, The University of Toledo, Toledo, Ohio, United States of America
| | - Xingjian Jin
- Department of Pharmacology, The University of Toledo, Toledo, Ohio, United States of America
| | - Shakila Abdul-Majeed
- Department of Pharmacology, The University of Toledo, Toledo, Ohio, United States of America
| | - Andromeda M. Nauli
- Department of Health Sciences, East Tennessee State University, Johnson City, Tennessee, United States of America
| | - Youssef Sari
- Department of Pharmacology, The University of Toledo, Toledo, Ohio, United States of America
| | - Surya M. Nauli
- Department of Pharmacology, The University of Toledo, Toledo, Ohio, United States of America
- * E-mail:
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Shoshani YZ, Harris A, Shoja MM, Rusia D, Siesky B, Arieli Y, Wirostko B. Endothelin and Its Suspected Role in the Pathogenesis and Possible Treatment of Glaucoma. Curr Eye Res 2011; 37:1-11. [DOI: 10.3109/02713683.2011.622849] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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10
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Liu XR, Zhang MF, Yang N, Liu Q, Wang RX, Cao YN, Yang XR, Sham JSK, Lin MJ. Enhanced store-operated Ca²+ entry and TRPC channel expression in pulmonary arteries of monocrotaline-induced pulmonary hypertensive rats. Am J Physiol Cell Physiol 2011; 302:C77-87. [PMID: 21940663 DOI: 10.1152/ajpcell.00247.2011] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Pulmonary hypertension (PH) is associated with profound vascular remodeling and alterations in Ca(2+) homeostasis in pulmonary arterial smooth muscle cells (PASMCs). Previous studies show that canonical transient receptor potential (TRPC) genes are upregulated and store-operated Ca(2+) entry (SOCE) is augmented in PASMCs of chronic hypoxic rats and patients of pulmonary arterial hypertension (PAH). Here we further examine the involvement of TRPC and SOCE in PH with a widely used rat model of monocrotaline (MCT)-induced PAH. Rats developed severe PAH, right ventricular hypertrophy, and significant increase in store-operated TRPC1 and TRPC4 mRNA and protein in endothelium-denuded pulmonary arteries (PAs) 3 wk after MCT injection. Contraction of PA and Ca(2+) influx in PASMC evoked by store depletion using cyclopiazonic acid (CPA) were enhanced dramatically, consistent with augmented SOCE in the MCT-treated group. The time course of increase in CPA-induced contraction corresponded to that of TRPC1 expression. Endothelin-1 (ET-1)-induced vasoconstriction was also potentiated in PAs of MCT-treated rats. The response was partially inhibited by SOCE blockers, including Gd(3+), La(3+), and SKF-96365, as well as the general TRPC inhibitor BTP-2, suggesting that TRPC-dependent SOCE was involved. Moreover, the ET-1-induced contraction and Ca(2+) response in the MCT group were more susceptible to the inhibition caused by the various SOCE blockers. Hence, our study shows that MCT-induced PAH is associated with increased TRPC expression and SOCE, which are involved in the enhanced vascular reactivity to ET-1, and support the hypothesis that TRPC-dependent SOCE is an important pathway for the development of PH.
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Affiliation(s)
- Xiao-Ru Liu
- Department of Physiology and Pathophysiology, Fujian Medical University, Fuzhou, Fujian Province, People's Republic of China
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11
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Avedanian L, Riopel J, Bkaily G, Nader M, D'Orleans-Juste P, Jacques D. ETA receptors are present in human aortic vascular endothelial cells and modulate intracellular calcium. Can J Physiol Pharmacol 2011; 88:817-29. [PMID: 20725140 DOI: 10.1139/y10-057] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Using immunofluorescence and real 3-D confocal microscopy, our results showed the presence of ET-1, ETA, and ETB receptors in isolated human aortic vascular endothelial cells (hVECs). The level of the peptide and its receptors was significantly higher in the nucleus (including the nuclear envelope membranes) than in the cytosol (including the cell membrane). Furthermore, using the Western blot technique we demonstrated the presence of both ETA and ETB receptors. Using intact and isolated human hVECs and the Fura-2 calcium (Ca2+) measurement technique, we showed that ET-1 induced a dose-dependent increase of total intracellular free Ca2+, with an EC50 of 1.3 x 10-10 mol/L. The specific ETA receptor antagonist ABT-627 (10-7 mol/L), but not the ETB receptor antagonist A-192621 (10-7 mol/L), prevented the ET-1 (10-9 mol/L) induced increase of total intracellular Ca2+. In conclusion, these results clearly show that similar to ETB receptors, ETA receptors are also present in human aortic vascular endothelial cells and their levels are higher than ETB in the nucleus when compared with the cytosol. Furthermore, we suggest that ETA, but not ETB, receptors mediate the effect of ET-1 on total intracellular Ca2+ of human aortic vascular endothelial cells.
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Affiliation(s)
- Levon Avedanian
- Department of Anatomy and Cell Biology, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, QC J1H5N4, Canada
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Jung KJ, Kim DW, Lee HN, Lee YS, Lee SJ, Che JH, Lee YH, Kang BC. The role of endothelin receptor A during myelination of developing oligodendrocytes. J Korean Med Sci 2011; 26:92-9. [PMID: 21218036 PMCID: PMC3012856 DOI: 10.3346/jkms.2011.26.1.92] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Accepted: 10/01/2010] [Indexed: 11/20/2022] Open
Abstract
Endothelin (ET)-1 and its receptors (ETA and ETB receptor) are present in the central nervous system. ET exerts biological effects on gliogenesis and glial cell functions. In order to define a possible mechanism of ETA receptor signaling, the distribution of the ETA receptor in developing oligodendrocytes and the effects of ET-1 on the myelination of oligodendrocytes were examined. ETA receptor immunoreactivity was confined to the perivascular elements of the blood vessels during early postnatal development. However later in development, ETA receptor immunoreactivity was no longer observed in the vessels but became localized to the myelinating oligodendrocytes of the primitive corpus callosum of the white matter, apart from the vessels. ET-1 induced myelin basic protein (MBP) in primary oligodendrocyte precursor cell culture though the ETA receptor and was blocked by an ETA receptor antagonist. In addition, ET-1 evoked the release of Ca(2+) which is a central regulator of oligodendrocyte differentiation. Our results provide a link between ET-1 and its ETA receptor and myelination during oligodendrocyte differentiation.
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Affiliation(s)
- Kyung Jin Jung
- Department of Anatomy, Institute for Brain Research, Chungnam National University School of Medicine, Daejeon, Korea
| | - Dong Woon Kim
- Department of Anatomy, Institute for Brain Research, Chungnam National University School of Medicine, Daejeon, Korea
| | - Ha Na Lee
- Department of Anatomy, Institute for Brain Research, Chungnam National University School of Medicine, Daejeon, Korea
| | - Young Sook Lee
- Department of Anatomy, Institute for Brain Research, Chungnam National University School of Medicine, Daejeon, Korea
| | - Sung Joong Lee
- Department of Oral Physiology, School of Dentistry, Seoul National University, Seoul, Korea
| | - Jeong-Hwan Che
- Department of Experimental Animal Research, Clinical Research Institute, Seoul National University Hospital, Seoul, Korea
| | - Young Ho Lee
- Department of Anatomy, Institute for Brain Research, Chungnam National University School of Medicine, Daejeon, Korea
| | - Byeong-Cheol Kang
- Department of Experimental Animal Research, Clinical Research Institute, Seoul National University Hospital, Seoul, Korea
- Graduate School of Immunology, College of Medicine, Seoul National University, Seoul, Korea
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13
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Li Y, Tang J, Khatibi NH, Zhu M, Chen D, Tu L, Chen L, Wang S. Treatment with ginsenoside rb1, a component of panax ginseng, provides neuroprotection in rats subjected to subarachnoid hemorrhage-induced brain injury. ACTA NEUROCHIRURGICA. SUPPLEMENT 2011; 110:75-9. [PMID: 21125449 DOI: 10.1007/978-3-7091-0356-2_14] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE recent trials have shown Ginsenoside Rb1 (GRb1), an active component of a well known Chinese medicine Panax Ginseng, plays a significant role in improving the complications seen after an ischemic brain event. In the present study, we investigated the use of GRb1 as a treatment modality to reduce brain edema, reduce arterial vasospasm, and improve neurobehavioral function after subarachnoid hemorrhage-induced brain injury (SAH) in rats. METHOD male Sprague-Dawley rats weighing between 250 and 300 g were randomly assigned to three groups: (1) Sham group (n = 10), (2) Vehicle group (SAH + no treatment; n = 12); (3) Treatment group (SAH + GRb1 treatment at 20 mg/kg; n = 11). Subarachnoid hemorrhage was induced using the modified double hemorrhage model followed by treatment administration intravenously. Post-operative assessment included neurobehavioral testing using the spontaneous activity scoring system, brain water content, and histological examination of the basilar artery. RESULTS post-operative findings indicated treatment with GRb1 had significantly reduced brain edema and improved neurobehavioral functioning. In addition, histological examination revealed a significant reduction in basilar artery vasospasm and lumen thickness with treatment. CONCLUSION the results of the study suggest that GRb1 treatment reduces brain edema, improves neurobehavioral function, and blocks vasculature thickening and spasm after SAH in rats. Given the novelty of the study, further research will be needed to confirm the benefits of treatment and mechanisms behind neuroprotection.
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Affiliation(s)
- Yingbo Li
- Institute of Neuroscience, Chongqing Medical University, Chongqing, 400016, China
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14
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Abstract
The 21-amino-acid peptide ET-1 (endothelin-1) regulates a diverse array of physiological processes, including vasoconstriction, angiogenesis, nociception and cell proliferation. Most of the effects of ET-1 are associated with an increase in intracellular calcium concentration. The calcium influx and mobilization pathways activated by ET-1, however, vary immensely. The present review begins with the basics of calcium signalling and investigates the different ways intracellular calcium concentration can increase in response to a stimulus. The focus then shifts to ET-1, and discusses how ET receptors mobilize calcium. We also examine how disease alters calcium-dependent responses to ET-1 by discussing changes to ET-1-mediated calcium signalling in hypertension, as there is significant interest in the role of ET-1 in this important disease. A list of unanswered questions regarding ET-mediated calcium signals are also presented, as well as perspectives for future research of calcium mobilization by ET-1.
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Affiliation(s)
- Nathan R Tykocki
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA.
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15
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Oxidant sensing by protein kinases a and g enables integration of cell redox state with phosphoregulation. SENSORS 2010; 10:2731-51. [PMID: 22319269 PMCID: PMC3274199 DOI: 10.3390/s100402731] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 03/19/2010] [Accepted: 03/22/2010] [Indexed: 12/19/2022]
Abstract
The control of vascular smooth muscle contractility enables regulation of blood pressure, which is paramount in physiological adaptation to environmental challenges. Maintenance of stable blood pressure is crucial for health as deregulation (caused by high or low blood pressure) leads to disease progression. Vasotone is principally controlled by the cyclic nucleotide dependent protein kinases A and G, which regulate intracellular calcium and contractile protein calcium sensitivity. The classical pathways for activation of these two kinases are well established and involve the formation and activation by specific cyclic nucleotide second messengers. Recently we reported that both PKA and PKG can be regulated independently of their respective cyclic nucleotides via a mechanism whereby the kinases sense cellular oxidant production using redox active thiols. This novel redox regulation of these kinases is potentially of physiological importance, and may synergise with the classical regulatory mechanisms.
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16
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Gouadon E, Meunier N, Grebert D, Durieux D, Baly C, Salesse R, Caillol M, Congar P. Endothelin evokes distinct calcium transients in neuronal and non-neuronal cells of rat olfactory mucosa primary cultures. Neuroscience 2010; 165:584-600. [PMID: 19861152 DOI: 10.1016/j.neuroscience.2009.10.046] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Revised: 09/30/2009] [Accepted: 10/21/2009] [Indexed: 01/29/2023]
Abstract
The olfactory system is regulated by several nervous and hormonal factors, and there is a growing body of evidence that some of these modulations already take place in the olfactory mucosa (OM). We recently suggested that, among others, vasoactive peptides might play multifaceted roles in different OM cells. Here we studied the effect of the vasoconstrictive peptide endothelin (ET) in the rat OM. We identified different components of the ET system both in the olfactory mucosa and in long-term primary culture of OM cells, composed of olfactory sensory neurons (OSNs) lying on a blend of non-neuronal OM cells (nNCs). We demonstrated that ET receptors are differentially expressed on OM cells, and that ET might be locally matured by the endothelin-converting enzyme ECE-1 located in OSNs. Using calcium imaging, we showed that ET triggers robust dose-dependent Ca(2+) responses in most OM cells, which consist of a transient phase, followed, in nNCs, by a sustained plateau phase. All transient responses depended on intracellular calcium release, while the sustained plateau phase also depended on subsequent external calcium entry. Using both pharmacology and spotting lethal (sl/sl) mutant rats, lacking functional ET(B) receptors, we finally demonstrated that these effects of ET are mediated through ET(B) receptors in OSNs and ET(A) receptors in nNCs.The present study therefore identifies endothelin as a potent endogenous modulator of the olfactory mucosa; specific endothelin-mediated Ca(2+) signals may serve distinct signaling functions, and thereby suggest differential functional roles of endothelin in both neuronal and non-neuronal OM cells.
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Affiliation(s)
- E Gouadon
- INRA, UMR1197 Neurobiologie de l'Olfaction et de la Prise Alimentaire, Récepteurs et Communication Chimique, Domaine de Vilvert, Jouy en Josas, France
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17
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Liu Y, Yang J, Ren H, He D, Pascua A, Armando MI, Yang C, Zhou L, Felder RA, Jose PA, Zeng C. Inhibitory effect of ETB receptor on Na(+)-K(+) ATPase activity by extracellular Ca(2+) entry and Ca(2+) release from the endoplasmic reticulum in renal proximal tubule cells. Hypertens Res 2009; 32:846-52. [PMID: 19662022 DOI: 10.1038/hr.2009.112] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The kidney is important in the long-term regulation of blood pressure and sodium homeostasis. Stimulation of ETB receptors in the kidney increases sodium excretion, in part, by decreasing sodium transport in the medullary thick ascending limb of Henle and in collecting duct. However, the role of ETB receptor on Na(+)-K(+) ATPase activity in renal proximal tubule (RPT) cells is not well defined. The purpose of this study is to test the hypothesis that ETB receptor inhibits Na(+)-K(+) ATPase activity in rat RPT cells, and investigate the mechanism(s) by which such an action is produced. In RPT cells from Wistar-Kyoto rats, stimulation of ETB receptors by the ETB receptor agonist, BQ3020, decreased Na(+)-K(+) ATPase activity, determined by ATP hydrolysis (control=0.38+/-0.02, BQ3020=0.26+/-0.03, BQ788=0.40+/-0.06, BQ3020+BQ788=0.37+/-0.04, n=5, P<0.01). The ETB receptor-mediated inhibition of Na(+)-K(+) ATPase activity was dependent on an increase in intracellular calcium, because this effect was abrogated by a chelator of intracellular-free calcium (BAPTA-AM; 5 x 10(-3) M 15 min(-1)), Ca(2+) channel blocker (10(-6) M 15 min(-1) nicardipine) and PI3 kinase inhibitor (10(-7) M per wortmannin). An inositol 1,4,5-trisphosphate (IP3) receptor blocker (2-aminoethyl diphenyl borate; 10(-4) M 15 min(-1)) also blocked the inhibitory effect of the ETB receptor on Na(+)-K(+)ATPase activity (control=0.39+/-0.06, BQ3020=0.25+/-0.01, 2-APB=0.35+/-0.05, BQ3020+ 2-APB=0.35+/-0.06, n=4, P<0.01). The calcium channel agonist (BAY-K8644; 10(-6) M 15 min(-1)) inhibited Na(+)-K(+) ATPase activity, an effect that was blocked by a phosphatidylinositol-3 kinase inhibitor (10(-7) M 15 min(-1) wortmannin). In rat RPT cells, activation of the ETB receptor inhibits Na(+)-K(+) ATPase activity by facilitating extracellular Ca(2+) entry and Ca(2+) release from endoplasmic reticulum.
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Affiliation(s)
- Yan Liu
- Department of Cardiology, Daping Hospital, The Third Military Medical University, Chongqing, PR China
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18
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Walsh SK, Kane KA, Wainwright CL. Mast cell degranulation--a mechanism for the anti-arrhythmic effect of endothelin-1? Br J Pharmacol 2009; 157:716-23. [PMID: 19422371 DOI: 10.1111/j.1476-5381.2009.00222.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE The aim of this study was to investigate whether the previously reported anti-arrhythmic effect of endothelin-1 (ET-1) is mediated by degranulation of cardiac mast cells prior to myocardial ischaemia. EXPERIMENTAL APPROACH Male Sprague-Dawley rats received either ET-1 (1.6 nmolxkg(-1)) in the presence or absence of disodium cromoglycate (DSCG; 20 mgxkg(-1)xh(-1)) prior to coronary artery occlusion (CAO). In separate experiments rats were given compound 48/80 (50 microgxkg(-1)) to compare the effects of ET-1 with those of a known mast cell degranulator. Ischaemia-induced ventricular arrhythmias were detected through continuous monitoring of a lead I electrocardiogram. After 30 min of CAO, the hearts were removed and mast cell degranulation determined by histological analysis. A parallel series of sham groups were performed to determine the direct effects of ET-1 and compound 48/80 on mast cell degranulation in the absence of ischaemia. KEY RESULTS ET-1 and compound 48/80 both exerted profound anti-arrhythmic effects, significantly reducing the total number of ventricular ectopic beats (P < 0.001) and the incidence of ventricular fibrillation (P < 0.05). These anti-arrhythmic effects were abolished by concomitant DSCG infusion prior to CAO. In sham animals ET-1 and compound 48/80 both induced mast cell degranulation (P < 0.001), an effect which was abolished by DSCG, confirming their ability to induce degranulation of mast cells. CONCLUSIONS AND IMPLICATIONS These results demonstrate for the first time that when given prior to ischaemia ET-1 mediates its anti-arrhythmic effects, at least in part, via cardiac mast cell degranulation.
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Affiliation(s)
- S K Walsh
- School of Pharmacy and Life Sciences, The Robert Gordon University, Aberdeen, Scotland, UK
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19
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So CH, Verma V, Alijaniaram M, Cheng R, Rashid AJ, O'Dowd BF, George SR. Calcium signaling by dopamine D5 receptor and D5-D2 receptor hetero-oligomers occurs by a mechanism distinct from that for dopamine D1-D2 receptor hetero-oligomers. Mol Pharmacol 2009; 75:843-54. [PMID: 19171671 DOI: 10.1124/mol.108.051805] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In this report, we investigated whether the D5 dopamine receptor, given its structural and sequence homology with the D1 receptor, could interact with the D2 receptor to mediate a calcium signal similar to the G(q/11) protein-linked phospholipase C-mediated calcium signal resulting from the coactivation of D1 and D2 dopamine receptors within D1-D2 receptor heterooligomers. Fluorescent resonance energy transfer experiments demonstrated close colocalization of cell surface D5 and D2 receptors (<100 A), indicating hetero-oligomerization of D5 and D2 receptors in cells coexpressing both receptors. Coactivation of D5 and D2 receptors within the D5-D2 hetero-oligomers activated a calcium signal. However, unlike what is observed for D1 receptors, which activate extensive calcium mobilization only within a complex with the D2 receptors, a robust calcium signal was triggered by D5 receptors expressed alone. Hetero-oligomerization with the D2 receptor attenuated the ability of the D5 receptor to trigger a calcium signal. The D5 and D5-D2-associated calcium signals were G(q/11) protein-linked and phospholipase C-mediated but were also critically dependent on the influx of extracellular calcium through store-operated calcium channels, unlike the calcium release triggered by D1-D2 heterooligomers. Collectively, these results demonstrate that calcium signaling through D5-D2 receptor hetero-oligomers occurred through a distinct mechanism to achieve an increase in intracellular calcium levels.
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Affiliation(s)
- Christopher H So
- Department of Pharmacology, University of Toronto, and the Centre for Addiction and Mental Health, Toronto, Ontario, Canada
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20
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Inhibition of cerebral vasoconstriction by dantrolene and nimodipine. Neurocrit Care 2008; 10:93-102. [PMID: 18923817 DOI: 10.1007/s12028-008-9153-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2008] [Accepted: 09/15/2008] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Cerebral vasoconstriction is associated with increased cytosolic Ca(2+) concentration in vascular smooth muscle, presumably due to Ca(2+) influx and Ca(2+) release from intracellular stores. We tested the hypothesis that dantrolene (a blocker of Ca(2+)-induced Ca(2+) release from the ryanodine receptor channel on the sarco-endoplasmic reticulum) would potentiate the action of nimodipine (a voltage-dependent L-type Ca(2+) channel blocker, considered standard therapy for SAH) in inhibiting the vasoconstriction of isolated cerebral arteries. METHOD Sprague-Dawley rat basilar and femoral arteries were analyzed for ryanodine receptor expression by immunofluorescence and PCR. Vasoconstriction of basilar artery ex vivo was measured in a wire myograph while exposed to serotonin (5-HT) or endothelin-1 (ET-1) in the presence or absence of dantrolene (10-100 muM) and/or nimodipine (30 nM). Femoral artery was examined for comparison. RESULTS Basilar and femoral arteries express only the ryanodine receptor 3 (RyR3) isoform. In both basilar and femoral arteries, dantrolene significantly inhibited the constriction to 5-HT, whereas it poorly affected the constriction to ET-1. The inhibitory effect of dantrolene on 5-HT was substantially increased by nimodipine, inducing a 10-fold increase in the 50% effective concentration of 5-HT and a 46% reduction in maximum basilar constriction. In femoral artery, dantrolene modestly affected constriction to phenylephrine and there was no interaction with nimodipine. CONCLUSION Dantrolene has synergistic effects with nimodipine against 5-HT-induced vasoconstriction in isolated cerebral arteries. Dantrolene-nimodipine interaction will require testing in a pathophysiological model but might provide treatment for reducing SAH-related vasospasm or other 5-HT-related vasospastic syndromes, such as Call-Fleming syndrome.
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21
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Oliveira VH, Nascimento KSO, Freire MM, Moreira OC, Scofano HM, Barrabin H, Mignaco JA. Mechanism of modulation of the plasma membrane Ca(2+)-ATPase by arachidonic acid. Prostaglandins Other Lipid Mediat 2008; 87:47-53. [PMID: 18718873 DOI: 10.1016/j.prostaglandins.2008.07.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2007] [Revised: 07/15/2008] [Accepted: 07/22/2008] [Indexed: 10/25/2022]
Abstract
The intracellular level of long chain fatty acids controls the Ca(2+) concentration in the cytoplasm. The molecular mechanisms underlying this Ca(2+) mobilization are not fully understood. We show here that the addition of low micromolar concentrations of fatty acids directly to the purified plasma membrane Ca(2+)-ATPase enhance ATP hydrolysis, while higher concentration decrease activity, exerting a dual effect on the enzyme. The effect of arachidonic acid is similar in the presence or absence of calmodulin, acidic phospholipids or ATP at the regulatory site, thereby precluding these sites as probable acid binding sites. At low arachidonic acid concentrations, neither the affinity for calcium nor the phosphoenzyme levels are significantly modified, while at higher concentrations both are decreased. The action of arachidonic acid is isoenzyme specific. The increase on ATP hydrolysis, however, is uncoupled from calcium transport, because arachidonic acid increases the permeability of erythrocyte membranes to calcium. Oleic acid has no effect on membrane permeability while linoleic acid shows an effect similar to that of arachidonic acid. Such effects might contribute to the entry of extracellular Ca(2+) following to fatty acid release.
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Affiliation(s)
- Vanessa H Oliveira
- Instituto de Bioquímica Médica, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ, Brazil
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22
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Meidan R, Levy N. The ovarian endothelin network: an evolving story. Trends Endocrinol Metab 2007; 18:379-85. [PMID: 17997104 DOI: 10.1016/j.tem.2007.09.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2007] [Revised: 09/09/2007] [Accepted: 09/11/2007] [Indexed: 11/19/2022]
Abstract
The endothelin (ET) system consists of three ET isopeptides, several converting enzyme isoforms and two G-protein-coupled receptors, ETA and ETB, which are linked to multiple signaling pathways. Less than 20 years after the initial detection of ET-1 in granulosa cells, the ovarian ET network continues to expand with the discovery of new members and functions. ETs influence a broad range of essential reproductive processes, such as ovulation, steroidogenesis and luteolysis. Therefore, a more comprehensive understanding of the ovarian ET network might provide new strategies for controlling reproduction. This review presents up-to-date findings on the ET network in the ovary.
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Affiliation(s)
- Rina Meidan
- Department of Animal Sciences, Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
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23
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Dai J, Lee CH, Poburko D, Szado T, Kuo KH, van Breemen C. Endothelin-1-mediated wave-like [Ca2+]i oscillations in intact rabbit inferior vena cava. J Vasc Res 2007; 44:495-503. [PMID: 17657165 DOI: 10.1159/000106553] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2007] [Accepted: 04/13/2007] [Indexed: 11/19/2022] Open
Abstract
Endothelin-1 (ET1) is an endogenous vasoconstrictor released by the vascular system to regulate the contractility of vascular smooth muscle cells (VSMC). It is implicated in the pathogenesis of hypertension and diabetic vasculopathy. In rabbit inferior vena cava (IVC), 10 nM ET1 induces tonic contraction mainly via type A endothelin receptor activation. Using confocal imaging of Fluo-3 loaded in thein situ VSMC within the intact IVC, we found that ET1 elicited [Ca2+]i oscillations with an average frequency of 0.31 +/- 0.01 Hz. These [Ca2+]i oscillations occurred as repetitive Ca2+ waves traveling along the longitudinal axis of the cells with an average velocity of 29 +/- 3 microm/s. The Ca2+ waves were not synchronized between neighboring VSMC nor were they propagated between them. Nifedipine (10 microM) inhibited the tonic contraction by 27.0 +/- 5.0% while SKF96365 (50 microM) abolished the remaining contraction. In a parallel Ca2+ study, nifedipine reduced the frequency of the oscillations to 0.22 +/- 0.01 Hz while SKF96365 abolished the remaining [Ca2+]i oscillations. Subsequent application of 25 mM caffeine elicited no further Ca2+ signal. Thus, we conclude that ET1 stimulates tonic contraction in the rabbit IVC by inducing [Ca2+]i oscillations and that stimulated Ca2+ entry through both the L-type voltage-gated Ca2+ channels and a nifedipine-resistant and SKF96365-sensitive pathway is crucial for the maintenance of [Ca2+]i oscillations and tonic contraction.
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MESH Headings
- Animals
- Calcium Channel Blockers/pharmacology
- Calcium Channels/drug effects
- Calcium Channels/metabolism
- Calcium Channels, L-Type/metabolism
- Calcium Signaling/drug effects
- Endothelin-1/metabolism
- Endothelin-1/pharmacology
- Female
- Imidazoles/pharmacology
- In Vitro Techniques
- Microscopy, Confocal
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Nifedipine/pharmacology
- Oligopeptides/pharmacology
- Peptides, Cyclic/pharmacology
- Piperidines/pharmacology
- Rabbits
- Receptor, Endothelin A/drug effects
- Receptor, Endothelin A/metabolism
- Time Factors
- Vasoconstriction/drug effects
- Vasoconstrictor Agents/metabolism
- Vasoconstrictor Agents/pharmacology
- Vena Cava, Inferior/metabolism
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Affiliation(s)
- Jiazhen Dai
- The James Hogg iCAPTURE Centre for Cardiovascular and Pulmonary Research, University of British Columbia, Vancouver, B.C., Canada
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24
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Rao VR, Krishnamoorthy RR, Yorio T. Endothelin-1, endothelin A and B receptor expression and their pharmacological properties in GFAP negative human lamina cribrosa cells. Exp Eye Res 2007; 84:1115-24. [PMID: 17433294 DOI: 10.1016/j.exer.2007.02.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2006] [Revised: 02/02/2007] [Accepted: 02/12/2007] [Indexed: 11/18/2022]
Abstract
Primary open angle glaucoma (POAG) is a progressive optic neuropathy, characterized, in part by extensive extra cellular matrix remodeling and collapse of the lamina cribrosa (LC). Endothelin-1 (ET-1), a potent vasoactive peptide and its receptors, endothelin receptor A (ET(A)) and endothelin receptor B (ET(B)), have been implicated in glaucomatous optic neuropathy. In this study we examined the expression of ET-1 and its receptors in GFAP negative LC cells. RT-PCR analysis revealed that LC cells express both ET(A), ET(B) receptors and prepro- ET-1, the primary gene transcript of ET-1. A dose-dependent increase in intra-cellular calcium concentrations was observed in the presence of 1, 10 and 100nM ET-1. Increased intracellular calcium concentrations were blocked by the ET(A) selective antagonist BQ610 but not by the ET(B) specific antagonist BQ788. Desensitization to ET(A)-mediated increase in intracellular calcium was observed in LC cells following pre-treatment with ET-1 for 24h. Western blot analysis of LC cells treated with ET-1 for 24h revealed a decreased expression of ET(A) receptor protein at 1, 10 and 100nM concentrations, while a dose dependent increase in the ET(B) receptor was observed with a significant increase at 100nM. Quantitative PCR showed a dose-dependent decrease in ET(A) receptor mRNA levels and an increase in the mRNA levels of ET(B) receptors. A Griess colorimetric assay was used to measure the NO released from LC cells and ET-1 induced a dose-dependent increase in NO release which was significant at 100nM concentration. ET-1 induced NO release was significantly blocked by BQ788, an ET(B) selective antagonist, and as well as BQ610, an ET(A) selective antagonist. These results suggested that human lamina cribrosa cells expressed functional ET(A) and ET(B) receptors and their expression and function was altered in response to prolong exposure to ET-1. This may have an implication in the normal physiology of LC cells and in POAG subjects where elevated levels of ET-1 could impact LC function.
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Affiliation(s)
- Vidhya R Rao
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA
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25
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Yokomori H, Yoshimura K, Ohshima S, Nagai T, Fujimaki K, Nomura M, Oda M, Hibi T. The endothelin-1 receptor-mediated pathway is not involved in the endothelin-1-induced defenestration of liver sinusoidal endothelial cells. Liver Int 2006; 26:1268-76. [PMID: 17105593 DOI: 10.1111/j.1478-3231.2006.01365.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
BACKGROUND/AIMS We previously reported that endothelin (ET)-1 may be involved in the contraction of hepatic sinusoidal endothelial fenestrae (SEF). Rho has emerged as an important regulator of the actin cytoskeleton and consequently cell morphology. To clarify the role of ET receptors [endothelin A receptor (ETAR) and endothelin B receptor (ETBR)] in ET-1-induced defenestration, we studied the size of hepatic SEF under various experimental conditions. METHODS Liver sinusoidal endothelial cells (LSECs) isolated from rat livers by collagenase perfusion were cultured and divided into four groups: control, ET-1 (10(-6) -10(-10) M)-treated, ET-1+selective ETAR antagonist (BQ610)-treated and ET-1+ETBR antagonist (BQ788)-treated groups. SEF morphology was observed by scanning electron microscopy. Protein expressions of ETAR and ETBR, Rho A and phosphorylated myosin light-chain kinase were analyzed by Western blotting. F-actin stress fiber formation was observed by confocal microscopy. Active Rho was measured by Ren's modification. Intracellular free Ca2+ concentration ([Ca2+]i) was measured by fluorescence digital imaging using fura-2 AM by Aqua cosmos. RESULTS ET-1 induced a reduction in the number and size of SEF. ETAR antagonist pretreatment inhibited defenestration induced by low ET-1 concentrations (10(-8) -10(-10) M), whereas ETBR antagonist pretreatment did not block defenestration at low to high ET-1 concentrations (10(-6) -10(-10) M). F-actin stress fibers, Rho A levels and phosphorylated myosin light-chain kinase levels remained the same in various treatments. Active Rho was not detected in control and various treatments. ET-1 did not increase [Ca2+]i. Western blot showed prominent ETBR but scarce ETAR protein expression in LSECs. CONCLUSIONS The present findings demonstrated that ETBR- and ETAR-induced contractile mechanisms are not involved in ET-1-induced defenestration, and that Rho is also not activated. Therefore, ET-1 induces hepatic defenestration by mechanisms other than receptor-mediated contraction.
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Affiliation(s)
- Hiroaki Yokomori
- Department of Internal Medicine, Kitasato Medical Center Hospital, Saitama 364-8501, Japan.
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26
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Abstract
Bioregulators are naturally occurring organic compounds that regulate a multitude of biologic processes. Under natural circumstances, bioregulators are synthesized in minute quantities in a variety of living organisms and are essential for physiologic homeostasis. In the wrong hands, these compounds have the capability to be used as nontraditional threat agents that are covered by the prohibitions of the Chemical Weapons Convention and the Biological and Toxin Weapons Convention. Unlike traditional biowarfare/bioterrorism agents that have a latency period of hours to days,the onset of action of bioregulators may occur within minutes after host exposure. Concerns regarding the potential misuse of bioregulators for nefarious purposes relate to the ability of these nontraditional agents to induce profound physiologic effects.
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Affiliation(s)
- Elliott Kagan
- Department of Pathology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814-4799, USA.
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Puppala BL, Bhalla S, Matwyshyn G, Gulati A. Role of endothelin (ETA) receptors in neonatal morphine withdrawal. Peptides 2006; 27:1514-9. [PMID: 16293342 DOI: 10.1016/j.peptides.2005.10.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2005] [Revised: 10/14/2005] [Accepted: 10/14/2005] [Indexed: 11/21/2022]
Abstract
We have previously demonstrated role of central endothelin (ET) receptors in neonatal morphine tolerance. The present study was conducted to investigate involvement of central ET receptors in neonatal rat morphine withdrawal. The aim was to determine activation of G-proteins coupled to opioid and ET receptors by morphine and ET ligands in neonatal rat brains during morphine withdrawal. Pregnant female rats were rendered tolerant to morphine by chronic exposure to morphine pellets over 7 days. Withdrawal was induced on day 8 by removal of pellets. Rat pups were delivered by cesarean section 24 h after pellet removal. G-protein stimulation induced by morphine; ET-1; ETA receptor antagonist, BMS182874; and ETB receptor agonist, IRL1620, was determined in the brain of neonatal rats undergoing morphine withdrawal by [35S]GTPgammaS binding assay. Morphine-induced maximal stimulation of G-protein in morphine withdrawal group (83.60%) was significantly higher compared to placebo control group (66.81%). EC50 value for ET-1-induced G-protein stimulation during morphine withdrawal (170.60 nM) was higher than control (62.5 nM). BMS182874, did not stimulate GTP binding in control but significantly increased maximal stimulation of G-proteins in morphine withdrawal (86.07%, EC50 = 31.25 nM). IRL1620-induced stimulation of G-proteins was similar in control and morphine withdrawal. The present findings indicate involvement of central ETA receptors in neonatal morphine withdrawal.
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Affiliation(s)
- Bhagya L Puppala
- Department of Pediatrics and Neonatology, Advocate Lutheran General Children's Hospital, Park Ridge, IL 60068, USA
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