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Gao M, Wen W, Gu C, Zhang X, Yu Y, Li H. Coronary plaque burden predicts perioperative cardiovascular events after coronary endarterectomy. Front Cardiovasc Med 2023; 10:1175287. [PMID: 37363096 PMCID: PMC10289079 DOI: 10.3389/fcvm.2023.1175287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/23/2023] [Indexed: 06/28/2023] Open
Abstract
Background and aims The risk factors of perioperative and long-term cardiovascular events in patients undergoing coronary artery bypass grafting (CABG) with adjunctive coronary endarterectomy (CE) are not well determined. This study evaluated the clinical value of coronary plaque burden, coronary anatomic stenosis, and serum biomarkers for predicting perioperative cardiovascular events after off-pump CABG + CE. Methods This retrospective cohort single-center study enrolled 125 patients undergoing off-pump CABG + CE between February 2018 and September 2021 in China. Coronary plaque burden was reflected by the length of plaque removed by CE. Plaque length-max, which represents the plaque length in patients undergoing single-vessel CE and the maximum plaque length in patients undergoing multivessel CE, was calculated. The primary endpoint was perioperative myocardial infraction (PMI). Results Plaque length-max was significantly higher in patients with PMI than in those without PMI (2.4 ± 1.5 vs. 1.6 ± 0.9, p = .001). A threshold plaque length-max of 1.15 cm was an independent predictor of PMI (area under the curve: 0.67; sensitivity 87.9%; specificity 59.8%; p = .005). Patients with plaque length-max ≥1.15 had a > 5-fold increase in PMI after adjusting for confounding factors (odds ratio = 5.89; p = .002). Furthermore, interleukin-6 (Beta = .32: p = .028), CD68 (Beta = .34; p = .045), and osteopontin (Beta = .43; p = .008) were significantly correlated with plaque length-max. Conclusions Plaque length-max was superior to clinical cardiovascular risk factors in predicting PMI occurrence after off-pump CABG + CE, which might be associated with systemic and plaque inflammation state.
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Affiliation(s)
- Mingxin Gao
- Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Wanwan Wen
- Department of Nuclear Medicine, Molecular Imaging Lab, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Chengxiong Gu
- Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - XiaoLi Zhang
- Department of Nuclear Medicine, Molecular Imaging Lab, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Yang Yu
- Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
| | - Haiyang Li
- Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
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Shabbir A, Rathod KS, Khambata RS, Ahluwalia A. Sex Differences in the Inflammatory Response: Pharmacological Opportunities for Therapeutics for Coronary Artery Disease. Annu Rev Pharmacol Toxicol 2020; 61:333-359. [PMID: 33035428 DOI: 10.1146/annurev-pharmtox-010919-023229] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Coordinated molecular responses are key to effective initiation and resolution of both acute and chronic inflammation. Vascular inflammation plays an important role in initiating and perpetuating atherosclerotic disease, specifically at the site of plaque and subsequent fibrous cap rupture. Both men and women succumb to this disease process, and although management strategies have focused on revascularization and pharmacological therapies in the acute situation to reverse vessel closure and prevent thrombogenesis, data now suggest that regulation of host inflammation may improve both morbidity and mortality, thus supporting the notion that prevention is better than cure. There is a clear sex difference in the incidence of vascular disease, and data confirm biological differences in inflammatory initiation and resolution between men and women. This article reviews contemporary opinions describing the sex difference in the initiation and resolution of inflammatory responses, with a view to explore potential targets for pharmacological intervention.
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Affiliation(s)
- Asad Shabbir
- The William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, United Kingdom;
| | - Krishnaraj Sinhji Rathod
- The William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, United Kingdom;
| | - Rayomand Syrus Khambata
- The William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, United Kingdom;
| | - Amrita Ahluwalia
- The William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, United Kingdom;
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Triggle CR, Samuel SM, Ravishankar S, Marei I, Arunachalam G, Ding H. The endothelium: influencing vascular smooth muscle in many ways. Can J Physiol Pharmacol 2012; 90:713-38. [PMID: 22625870 DOI: 10.1139/y2012-073] [Citation(s) in RCA: 157] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The endothelium, although only a single layer of cells lining the vascular and lymphatic systems, contributes in multiple ways to vascular homeostasis. Subsequent to the 1980 report by Robert Furchgott and John Zawadzki, there has been a phenomenal increase in our knowledge concerning the signalling molecules and pathways that regulate endothelial - vascular smooth muscle communication. It is now recognised that the endothelium is not only an important source of nitric oxide (NO), but also numerous other signalling molecules, including the putative endothelium-derived hyperpolarizing factor (EDHF), prostacyclin (PGI(2)), and hydrogen peroxide (H(2)O(2)), which have both vasodilator and vasoconstrictor properties. In addition, the endothelium, either via transferred chemical mediators, such as NO and PGI(2), and (or) low-resistance electrical coupling through myoendothelial gap junctions, modulates flow-mediated vasodilatation as well as influencing mitogenic activity, platelet aggregation, and neutrophil adhesion. Disruption of endothelial function is an early indicator of the development of vascular disease, and thus an important area for further research and identification of potentially new therapeutic targets. This review focuses on the signalling pathways that regulate endothelial - vascular smooth muscle communication and the mechanisms that initiate endothelial dysfunction, particularly with respect to diabetic vascular disease.
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Affiliation(s)
- Chris R Triggle
- Department of Pharmacology, Weill Cornell Medical College in Qatar, P.O. Box 24144, Education City, Doha, Qatar.
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Félétou M. The Endothelium, Part I: Multiple Functions of the Endothelial Cells -- Focus on Endothelium-Derived Vasoactive Mediators. ACTA ACUST UNITED AC 2011. [DOI: 10.4199/c00031ed1v01y201105isp019] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Ozkor MA, Murrow JR, Rahman AM, Kavtaradze N, Lin J, Manatunga A, Quyyumi AA. Endothelium-derived hyperpolarizing factor determines resting and stimulated forearm vasodilator tone in health and in disease. Circulation 2011; 123:2244-53. [PMID: 21555712 DOI: 10.1161/circulationaha.110.990317] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND We assessed the contribution of endothelium-derived hyperpolarizing factors to resting and agonist-stimulated vasodilator tone in health and disease. Tetraethylammonium chloride (TEA) was used to inhibit K(+)(Ca) channel activation and fluconazole was used to inhibit cytochrome P450 2C9-mediated epoxyeicosatrienoic acid synthesis. We hypothesized that endothelium-derived hyperpolarizing factors contribute to resting vascular tone by K(+)(Ca) channel activation and epoxyeicosatrienoic acid release and that endothelium-derived hyperpolarizing factors compensate for reduced nitric oxide bioavailability at rest and with endothelium-dependent vasodilators. METHODS AND RESULTS In 103 healthy subjects and 71 nonhypertensive subjects with multiple risk factors, we measured resting forearm blood flow (FBF) using venous occlusion plethysmography before and after intra-arterial infusions of N(G)-monomethyl-l-arginine (L-NMMA), TEA, fluconazole, and their combination. The effects of these antagonists on resting FBF and on bradykinin- and acetylcholine-mediated vasodilation were studied. Resting FBF decreased with TEA and L-NMMA in all subjects (P<0.001); however, the vasoconstrictor response to L-NMMA was greater (P=0.04) and to TEA was lower (P=0.04) in healthy subjects compared with those with risk factors. Fluconazole decreased resting FBF in all subjects, and the addition of TEA further reduced FBF after fluconazole, suggesting that cytochrome P450 metabolites and other hyperpolarizing factor(s) activate K(+)(Ca) channels. Both L-NMMA and TEA attenuated bradykinin-mediated vasodilation in healthy and hypercholesterolemic subjects (P<0.001). In contrast, acetylcholine-mediated vasodilation remained unchanged with TEA in healthy subjects but was significantly attenuated in hypercholesterolemia (P<0.04). CONCLUSIONS First, by activating TEA-inhibitable K(+)(Ca) channels, endothelium-derived hyperpolarizing factors, together with nitric oxide, contribute to resting microvascular dilator tone. The contribution of K(+)(Ca) channel activation compared with nitric oxide is greater in those with multiple risk factors compared with healthy subjects. Second, activation of K(+)(Ca) channels is only partly through epoxyeicosatrienoic acid release, indicating the presence of other hyperpolarizing mechanisms. Third, bradykinin, but not acetylcholine, stimulates K(+)(Ca) channel-mediated vasodilation in healthy subjects, whereas in hypercholesterolemia, K(+)(Ca) channel-mediated vasodilation compensates for the reduced nitric oxide activity. Thus, enhanced endothelium-derived hyperpolarizing factor activity in conditions of nitric oxide deficiency contributes to maintenance of resting and agonist-stimulated vasodilation. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00166166.
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Affiliation(s)
- Muhiddin A Ozkor
- Emory Clinical Cardiovascular Research Institute, Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA, USA
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Triggle CR, Ding H. A review of endothelial dysfunction in diabetes: a focus on the contribution of a dysfunctional eNOS. ACTA ACUST UNITED AC 2010; 4:102-15. [PMID: 20470995 DOI: 10.1016/j.jash.2010.02.004] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Revised: 01/25/2010] [Accepted: 02/04/2010] [Indexed: 12/31/2022]
Abstract
Although the etiology of vascular dysfunction in diabetes has been extensively investigated in both humans as well as animal models of human diabetes, the relative importance of the cellular pathways involved is still not fully understood. In this review, we focus on reviewing the literature that provides insights into how an acute exposure to hyperglycemia results in a dysregulation of endothelial nitric oxide synthase function, the subsequent downstream effects of endothelial nitric oxide synthase dysregulation, and the development of endothelial dysfunction.
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Affiliation(s)
- Chris R Triggle
- Department of Medical Education, Weill Cornell Medical College in Qatar, Education City, Doha, Qatar.
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Affiliation(s)
- Daniel A. Duprez
- From the Cardiovascular Division, Medical School, University of Minnesota, Minneapolis, Minn
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Félétou M. Calcium-activated potassium channels and endothelial dysfunction: therapeutic options? Br J Pharmacol 2009; 156:545-62. [PMID: 19187341 DOI: 10.1111/j.1476-5381.2009.00052.x] [Citation(s) in RCA: 191] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
The three subtypes of calcium-activated potassium channels (K(Ca)) of large, intermediate and small conductance (BK(Ca), IK(Ca) and SK(Ca)) are present in the vascular wall. In healthy arteries, BK(Ca) channels are preferentially expressed in vascular smooth muscle cells, while IK(Ca) and SK(Ca) are preferentially located in endothelial cells. The activation of endothelial IK(Ca) and SK(Ca) contributes to nitric oxide (NO) generation and is required to elicit endothelium-dependent hyperpolarizations. In the latter responses, the hyperpolarization of the smooth muscle cells is evoked either via electrical coupling through myo-endothelial gap junctions or by potassium ions, which by accumulating in the intercellular space activate the inwardly rectifying potassium channel Kir2.1 and/or the Na(+)/K(+)-ATPase. Additionally, endothelium-derived factors such as cytochrome P450-derived epoxyeicosatrienoic acids and under some circumstances NO, prostacyclin, lipoxygenase products and hydrogen peroxide (H(2)O(2)) hyperpolarize and relax the underlying smooth muscle cells by activating BK(Ca). In contrast, cytochrome P450-derived 20-hydroxyeicosatetraenoic acid and various endothelium-derived contracting factors inhibit BK(Ca). Aging and cardiovascular diseases are associated with endothelial dysfunctions that can involve a decrease in NO bioavailability, alterations of EDHF-mediated responses and/or enhanced production of endothelium-derived contracting factors. Because potassium channels are involved in these endothelium-dependent responses, activation of endothelial and/or smooth muscle K(Ca) could prevent the occurrence of endothelial dysfunction. Therefore, direct activators of these potassium channels or compounds that regulate their activity or their expression may be of some therapeutic interest. Conversely, blockers of IK(Ca) may prevent restenosis and that of BK(Ca) channels sepsis-dependent hypotension.
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Affiliation(s)
- Michel Félétou
- Department of Angiology, Institut de Recherches Servier, Suresnes, France.
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Villar IC, Panayiotou CM, Sheraz A, Madhani M, Scotland RS, Nobles M, Kemp-Harper B, Ahluwalia A, Hobbs AJ. Definitive role for natriuretic peptide receptor-C in mediating the vasorelaxant activity of C-type natriuretic peptide and endothelium-derived hyperpolarising factor. Cardiovasc Res 2007; 74:515-25. [PMID: 17391657 PMCID: PMC3503309 DOI: 10.1016/j.cardiores.2007.02.032] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Revised: 02/07/2007] [Accepted: 02/26/2007] [Indexed: 11/25/2022] Open
Abstract
OBJECTIVE C-type natriuretic peptide (CNP) has recently been suggested to represent an endothelium-derived hyperpolarising factor (EDHF) in the mammalian resistance vasculature and, as such, important in the regulation of local blood flow and systemic blood pressure. Additionally, this peptide has been shown to protect against ischaemia-reperfusion injury and inhibits leukocyte and platelet activation. Herein, we use a novel, selective natriuretic peptide receptor-C (NPR-C) antagonist (M372049) to highlight the pivotal contribution of CNP/NPR-C signalling in the EDHF-dependent regulation of vascular tone and investigate the mechanism(s) underlying the release and biological activity of CNP. METHODS In vitro pharmacological investigation was conducted in rat (Sprague-Dawley) aorta and mesenteric resistance arteries. Relaxant responses to CNP, atrial natriuretic peptide (ANP), the nitric oxide donor spermine-NONOate (SPER-NO) and the endothelium-dependent vasodilator, acetylcholine (ACh) were examined in the absence and presence of M372049 or inhibitor cocktails shown previously to block endothelium-dependent dilatation in the resistance vasculature. RT-PCR was employed to characterize the expression of NPR subtypes in the vessels studied. RESULTS M372049 produced concentration-dependent inhibition of the vasorelaxant activity of CNP in rat isolated mesenteric resistance arteries but not aorta; in contrast, M372049 did not affect relaxations to ANP or SPER-NO in either vessel. M372049 or ouabain alone produced small, significant inhibition of EDHF-dependent relaxations in mesenteric arteries and in combination acted synergistically to abolish such responses. A combination of M372049 with established inhibitors of EDHF-dependent relaxation revealed that multiple, distinct pathways coordinate the bioactivity of EDHF in the resistance vasculature, and that CNP/NPR-C signalling represents a major component. CONCLUSIONS These data substantiate CNP/NPR-C signalling as a fundamental pathway underlying EDHF-dependent regulation of vascular tone in the rat mesenteric resistance vasculature. An increased understanding of the physiological roles of CNP/NPR-C signalling in the vasculature (now facilitated by the identification of a selective NPR-C antagonist) should aid determination of the (patho)physiological importance of EDHF and might provide the rationale for the design of novel therapeutics.
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Affiliation(s)
- Inmaculada C. Villar
- Clinical Pharmacology, William Harvey Research Institute, Bart’s and The London, Charterhouse Square, London EC1M 6BQ, UK
| | - Catherine M. Panayiotou
- Wolfson Institute for Biomedical Research, University College London, Cruciform Building, Gower Street, London WC1E 6AE, UK
| | - Adil Sheraz
- Clinical Pharmacology, William Harvey Research Institute, Bart’s and The London, Charterhouse Square, London EC1M 6BQ, UK
| | - Melanie Madhani
- Wolfson Institute for Biomedical Research, University College London, Cruciform Building, Gower Street, London WC1E 6AE, UK
| | - Ramona S. Scotland
- Clinical Pharmacology, William Harvey Research Institute, Bart’s and The London, Charterhouse Square, London EC1M 6BQ, UK
| | - Muriel Nobles
- Wolfson Institute for Biomedical Research, University College London, Cruciform Building, Gower Street, London WC1E 6AE, UK
| | - Barbara Kemp-Harper
- Department of Pharmacology, Monash University, PO Box 13E, VIC 3800, Australia
| | - Amrita Ahluwalia
- Clinical Pharmacology, William Harvey Research Institute, Bart’s and The London, Charterhouse Square, London EC1M 6BQ, UK
| | - Adrian J. Hobbs
- Wolfson Institute for Biomedical Research, University College London, Cruciform Building, Gower Street, London WC1E 6AE, UK
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Jawien J, Csanyi G, Gajda M, Mateuszuk L, Lomnicka M, Korbut R, Chlopicki S. Ticlopidine attenuates progression of atherosclerosis in apolipoprotein E and low density lipoprotein receptor double knockout mice. Eur J Pharmacol 2007; 556:129-35. [PMID: 17174298 DOI: 10.1016/j.ejphar.2006.11.028] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Revised: 10/28/2006] [Accepted: 11/01/2006] [Indexed: 11/22/2022]
Abstract
Platelets are involved in the development of atherothrombosis. However, the anti-atherosclerotic effects of thienopiridines have not been, as yet, proven. We analyzed the effects of ticlopidine on atherogenesis in apolipoprotein E/low density lipoprotein receptor double knockout (apoE/LDLR(-/-)) mice. 2-month-old apoE/LDLR(-/-) mice fed a Western diet (21% fat, 0.15% cholesterol) were treated with ticlopidine (90 mg/kg/day) for a period of 4 months. In 6-month-old apoE/LDLR(-/-) mice treated with ticlopidine and in their non-treated counterparts we analyzed: cholesterol and triglyceride levels, the size of atherosclerotic plaques in aortic roots (oil red-O staining, cross-section method), and in the whole aorta (Sudan IV staining, en face method), the number of macrophages in atherosclerotic plaque (CD68 staining), as well as the endothelial function in the isolated thoracic aorta. Concentrations of total cholesterol and triglycerides in plasma were not altered by treatment with ticlopidine. However, the size of atherosclerotic plaques measured in aortic roots by the cross-section method and the number of macrophages estimated by anti-CD68 staining were significantly reduced by ticlopidine treatment. In contrast, the effect of ticlopidine on the area covered by plaques in the whole aorta (en face analysis) was not statistically significant. Importantly, acetylcholine-induced vasodilation in isolated aorta was improved in ticlopidine-treated apoE/LDLR(-/-) mice as compared to their non-treated counterparts. In conclusion, ticlopidine attenuates the progression of atherosclerosis and improves the endothelial function in apoE/LDLR(-/-) mice.
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Affiliation(s)
- Jacek Jawien
- Jagiellonian University Medical College, Krakow, Poland
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Abstract
Endothelium-dependent relaxations are attributed to the release of various factors, such as nitric oxide, carbon monoxide, reactive oxygen species, adenosine, peptides and arachidonic acid metabolites derived from the cyclooxygenases, lipoxygenases, and cytochrome P450 monooxygenases pathways. The hyperpolarization of the smooth muscle cell can contribute to or be an integral part of the mechanisms underlying the relaxations elicited by virtually all these endothelial mediators. These endothelium-derived factors can activate different families of K(+) channels of the vascular smooth muscle. Other events associated with the hyperpolarization of both the endothelial and the vascular smooth muscle cells (endothelium-derived hyperpolarizing factor (EDHF)-mediated responses) contribute also to endothelium-dependent relaxations. These responses involve an increase in the intracellular Ca(2+) concentration of the endothelial cells followed by the opening of Ca(2+)-activated K(+) channels of small and intermediate conductance and the subsequent hyperpolarization of these cells. Then, the endothelium-dependent hyperpolarization of the underlying smooth muscle cells can be evoked by direct electrical coupling through myoendothelial junctions and/or the accumulation of K(+) ions in the intercellular space between the two cell types. These various mechanisms are not necessarily mutually exclusive and, depending on the vascular bed and the experimental conditions, can occur simultaneously or sequentially, or also may act synergistically.
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Affiliation(s)
- Michel Félétou
- Department of Angiology, Institut de Recherches Servier, Suresnes, France
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Villar IC, Francis S, Webb A, Hobbs AJ, Ahluwalia A. Novel aspects of endothelium-dependent regulation of vascular tone. Kidney Int 2006; 70:840-53. [PMID: 16837917 DOI: 10.1038/sj.ki.5001680] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The vascular endothelium plays a crucial role in the regulation of vascular homeostasis and in preventing the initiation and progress of cardiovascular disease by controlling mechanical functions of the underlying vascular smooth muscle. Three vasodilators: nitric oxide (NO), prostacyclin, and endothelium-derived hyperpolarizing factor, produced by the endothelium, underlie this activity. These substances act in a co-ordinated interactive manner to maintain normal endothelial function and operate as support mechanisms when one pathway malfunctions. In this review, we discuss recent advances in our understanding of how gender influences the interaction of these factors resulting in the vascular protective effects seen in pre-menopausal women. We also discuss how endothelial NO synthase (NOS) can act in both a pro- and anti-inflammatory action and therefore is likely to be pivotal in the initiation and time course of an inflammatory response, particularly with respect to inflammatory cardiovascular disorders. Finally, we review recent evidence demonstrating that it is not solely NOS-derived NO that mediates many of the beneficial effects of the endothelium, in particular, nitrite acts as a store of NO released during pathological episodes associated with NOS inactivity (ischemia/hypoxia). Each of these more recent findings has emphasized new pathways involved in endothelial biology, and following further research and understanding of the significance and mechanisms of these systems, it is likely that new and improved treatments for cardiovascular disease will result.
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Affiliation(s)
- I C Villar
- Clinical Pharmacology, William Harvey Research Institute, Barts & The London Medical School, Charterhouse Square, London, UK
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Norton C, Kalea AZ, Harris PD, Klimis-Zacas DJ. Wild blueberry-rich diets affect the contractile machinery of the vascular smooth muscle in the Sprague-Dawley rat. J Med Food 2005; 8:8-13. [PMID: 15857202 DOI: 10.1089/jmf.2005.8.8] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Weanling male Sprague-Dawley rats were randomly fed a control diet (AIN-93) (C) or a blueberry diet (B) for 13 weeks, or a reverse diet (R) (C diet for 13 weeks, switched to the B diet for 8 weeks). Aortas were excised, and two intact and two endothelium-denuded rings were immersed in tissue baths containing physiological salt solution at 37 degrees C and aerated with 95% O(2) and 5% CO(2) (pH 7.4). Following equilibration and preconditioning under 1.5-g preload, cumulative dose-response curves were generated with six doses of the alpha1-adrenergic receptor-selective agonist L-phenylephrine (L-Phe, 10(8)-3 x 10(-6) M) and relaxed with one dose of acetylcholine (3 x 10(-6) M) to assess intact endothelium. The maximum force of contraction (Fmax) and vessel sensitivity (pD(2)) were determined in intact and endothelium-denuded rings. A two-way analysis of variance test revealed that blueberry-fed animals (B and R diets) developed a significantly lower F (max) (0.873 +/- 0.0463 and 0.9266 +/- 0.0463 g, respectively) when contracted with L-Phe, compared with the animals on the C diet (1.109 +/- 0.0463 g) (P < .05). The pD(2) of the intact rings was not significantly different among diet groups. Additionally, diet did not significantly affect the mean F (max) or pD(2) of endothelium-denuded rings. Our results indicate for the first time that wild blueberries incorporated into the diet affect the vascular smooth muscle contractile machinery by suppressing the alpha1-adrenergic receptor agonist-mediated contraction while having no effect on membrane sensitivity of the endothelial or vascular smooth muscle cell layer. Furthermore, their mechanism of action seems to be accomplished through an endothelium-dependent pathway.
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MESH Headings
- Acetylcholine/pharmacology
- Analysis of Variance
- Animals
- Aorta/drug effects
- Aorta/physiology
- Blueberry Plants
- Cross-Over Studies
- Dose-Response Relationship, Drug
- Male
- Muscle Contraction/drug effects
- Muscle Contraction/physiology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Phenylephrine/pharmacology
- Random Allocation
- Rats
- Rats, Sprague-Dawley
- Receptors, Adrenergic, alpha-1/drug effects
- Receptors, Adrenergic, alpha-1/physiology
- Vasoconstriction/drug effects
- Vasoconstriction/physiology
- Vasoconstrictor Agents/pharmacology
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Affiliation(s)
- Cynthia Norton
- Department of Food Science and Human Nutrition, College of Natural Sciences, Forestry and Agriculture, University of Maine, Orono, Maine 04469, USA
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Katusic ZS. Back to the salt mines-- endothelial dysfunction in hypertension and compensatory role of endothelium-derived hyperpolarizing factor (EDHF). J Physiol 2002; 543:1. [PMID: 12181276 PMCID: PMC2290466 DOI: 10.1113/jphysiol.2002.025478] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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