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Silva A, Hatch CJ, Chu MT, Cardinal TR. Collateral Arteriogenesis Involves a Sympathetic Denervation That Is Associated With Abnormal α-Adrenergic Signaling and a Transient Loss of Vascular Tone. Front Cardiovasc Med 2022; 9:805810. [PMID: 35242824 PMCID: PMC8886147 DOI: 10.3389/fcvm.2022.805810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 01/20/2022] [Indexed: 11/30/2022] Open
Abstract
Stimulating collateral arteriogenesis is an attractive therapeutic target for peripheral artery disease (PAD). However, the potency of arteriogenesis-stimulation in animal models has not been matched with efficacy in clinical trials. This may be because the presence of enlarged collaterals is not sufficient to relieve symptoms of PAD, suggesting that collateral function is also important. Specifically, collaterals are the primary site of vascular resistance following arterial occlusion, and impaired collateral vasodilation could impact downstream tissue perfusion and limb function. Therefore, we evaluated the effects of arteriogenesis on collateral vascular reactivity. Following femoral artery ligation in the mouse hindlimb, collateral functional vasodilation was impaired at day 7 (17 ± 3 vs. 60 ± 8%) but restored by day 28. This impairment was due to a high resting diameter (73 ± 4 μm at rest vs. 84 ± 3 μm dilated), which does not appear to be a beneficial effect of arteriogenesis because increasing tissue metabolic demand through voluntary exercise decreased resting diameter and restored vascular reactivity at day 7. The high diameter in sedentary animals was not due to sustained NO-dependent vasodilation or defective myogenic constriction, as there were no differences between the enlarged and native collaterals in response to eNOS inhibition with L-NAME or L-type calcium channel inhibition with nifedipine, respectively. Surprisingly, in the context of reduced vascular tone, vasoconstriction in response to the α-adrenergic agonist norepinephrine was enhanced in the enlarged collateral (−62 ± 2 vs. −37 ± 2%) while vasodilation in response to the α-adrenergic antagonist prazosin was reduced (6 ± 4% vs. 22 ± 16%), indicating a lack of α-adrenergic receptor activation by endogenous norepinephrine and suggesting a denervation of the neuroeffector junction. Staining for tyrosine hydroxylase demonstrated sympathetic denervation, with neurons occupying less area and located further from the enlarged collateral at day 7. Inversely, MMP2 presence surrounding the enlarged collateral was greater at day 7, suggesting that denervation may be related to extracellular matrix degradation during arteriogenesis. Further investigation on vascular wall maturation and the functionality of enlarged collaterals holds promise for identifying novel therapeutic targets to enhance arteriogenesis in patients with PAD.
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Bigalke JA, Carter JR. Sympathetic Neural Control in Humans with Anxiety-Related Disorders. Compr Physiol 2021; 12:3085-3117. [PMID: 34964121 DOI: 10.1002/cphy.c210027] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Numerous conceptual models are used to describe the dynamic responsiveness of physiological systems to environmental pressures, originating with Claude Bernard's milieu intérieur and extending to more recent models such as allostasis. The impact of stress and anxiety upon these regulatory processes has both basic science and clinical relevance, extending from the pioneering work of Hans Selye who advanced the concept that stress can significantly impact physiological health and function. Of particular interest within the current article, anxiety is independently associated with cardiovascular risk, yet mechanisms underlying these associations remain equivocal. This link between anxiety and cardiovascular risk is relevant given the high prevalence of anxiety in the general population, as well as its early age of onset. Chronically anxious populations, such as those with anxiety disorders (i.e., generalized anxiety disorder, panic disorder, specific phobias, etc.) offer a human model that interrogates the deleterious effects that chronic stress and allostatic load can have on the nervous system and cardiovascular function. Further, while many of these disorders do not appear to exhibit baseline alterations in sympathetic neural activity, reactivity to mental stress offers insights into applicable, real-world scenarios in which heightened sympathetic reactivity may predispose those individuals to elevated cardiovascular risk. This article also assesses behavioral and lifestyle modifications that have been shown to concurrently improve anxiety symptoms, as well as sympathetic control. Lastly, future directions of research will be discussed, with a focus on better integration of psychological factors within physiological studies examining anxiety and neural cardiovascular health. © 2022 American Physiological Society. Compr Physiol 12:1-33, 2022.
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Affiliation(s)
- Jeremy A Bigalke
- Department of Psychology, Montana State University, Bozeman, Montana, USA
| | - Jason R Carter
- Department of Psychology, Montana State University, Bozeman, Montana, USA.,Department of Health and Human Development, Montana State University, Bozeman, Montana, USA
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3
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Theodorakopoulou M, Raptis V, Loutradis C, Sarafidis P. Hypoxia and Endothelial Dysfunction in Autosomal-Dominant Polycystic Kidney Disease. Semin Nephrol 2020; 39:599-612. [PMID: 31836042 DOI: 10.1016/j.semnephrol.2019.10.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Autosomal-dominant polycystic kidney disease (ADPKD) is the most prevalent inherited kidney disease, characterized by growth of bilateral renal cysts, hypertension, and multiple extrarenal complications that eventually can lead to renal failure. It is caused by mutations in PKD1 or PKD2 genes encoding the proteins polycystin-1 and polycystin-2, respectively. Over the past few years, studies investigating the role of primary cilia and polycystins, present not only on the surface of renal tubular cells but also on vascular endothelial cells, have advanced our understanding of the pathogenesis of ADPKD and have shown that mechanisms other than cyst formation also contribute to renal functional decline in this disease. Among them, increased oxidative stress, endothelial dysfunction, and hypoxia may play central roles because they occur early in the disease process and precede the onset of hypertension and renal functional decline. Endothelial dysfunction is linked to higher asymmetric dimethylarginine levels and reduced nitric oxide bioavailability, which would cause regional vasoconstriction and impaired renal blood flow. The resulting hypoxia would increase the levels of hypoxia-inducible-transcription factor 1α and other angiogenetic factors, which, in turn, may drive cyst growth. In this review, we summarize the existing evidence for roles of endothelial dysfunction, oxidative stress, and hypoxia in the pathogenesis of ADPKD.
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Affiliation(s)
- Marieta Theodorakopoulou
- Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Vasileios Raptis
- Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Charalampos Loutradis
- Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Pantelis Sarafidis
- Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece..
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4
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The α1D-adrenoreceptor antagonist BMY 7378 reverses cardiac hypertrophy in spontaneously hypertensive rats. J Hypertens 2020; 38:1496-1503. [PMID: 32195823 DOI: 10.1097/hjh.0000000000002412] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE The α1D-adrenoreceptor (α1D-AR) is involved in angiotensin II-induced vascular remodeling and hypertension. Whether α1D-AR plays a role in hypertension-associated cardiac hypertrophy is unclear. Here we investigated effects of BMY 7378, a selective α1D-AR antagonist, on cardiac status in aged spontaneously hypertensive rats (SHR). METHODS Male SHR were studied during the phase of developing hypertension (5 and 10 weeks old) and once hypertension was established (20 and 30 weeks old) to assess the evolution of cardiac hypertrophy. Age-matched WKY rats were studied as controls. Thirty-week-old SHR were treated for 4 weeks with BMY 7378 (10 mg/kg per day, o.a.), or captopril (angiotensin-converting enzyme inhibitor, 40 mg/kg per day, o.a.) (as a positive control). Blood pressure and cardiac function were measured in vivo, cardiac hypertrophy by histology, and α1D-AR protein expression by immunofluorescence. RESULTS By 30 weeks of age, SHR exhibited significant hypertension and cardiac hypertrophy. BMY 7378 and captopril decreased blood pressure and improved hemodynamic parameters and cardiac function in treated SHR vs. untreated SHR (P < 0.05). Histology showed increased cardiomyocyte size, fibrosis, and left ventricular hypertrophy in SHR hearts. BMY 7378 ameliorated fibrosis and cardiac hypertrophy, but had no effect on cardiomyocyte size in SHR. Effects of BMY 7378 were associated with increased α1D-AR protein expression in SHR. CONCLUSION Our data indicate that pharmacological antagonism of α1D-AR reduces blood pressure and associated cardiac hypertrophy in aged SHR. These findings suggest that the α1D-AR plays a pathophysiological role in the development of hypertension and cardiac target organ damage in SHR.
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Tonhajzerova I, Olexova LB, Jurko A, Spronck B, Jurko T, Sekaninova N, Visnovcova Z, Mestanikova A, Kudela E, Mestanik M. Novel Biomarkers of Early Atherosclerotic Changes for Personalised Prevention of Cardiovascular Disease in Cervical Cancer and Human Papillomavirus Infection. Int J Mol Sci 2019; 20:E3720. [PMID: 31366035 PMCID: PMC6696433 DOI: 10.3390/ijms20153720] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 07/18/2019] [Accepted: 07/27/2019] [Indexed: 12/13/2022] Open
Abstract
Cervical cancer is associated with a causative role of human papillomavirus (HPV), which is a highly prevalent infection. Recently, women with a genital HPV infection were found to have increased incidence of cardiovascular diseases (CVD), including severe cardiovascular events such as myocardial infarction and stroke. The pathomechanisms of this relation are not yet fully understood, and may significantly affect the health of a large part of the population. Accelerated atherosclerosis is assumed to play a key role in the pathophysiology of this relationship. To identify high-risk groups of the population, it is necessary to stratify the CVD risk. Current algorithms, as widely used for the estimation of CVD risk, seem to be limited by the individual misclassification of high-risk subjects. However, personalised prediction of cardiovascular events is missing. Regarding HPV-related CVD, identification of novel sensitive biomarkers reflecting early atherosclerotic changes could be of major importance for such personalised cardiovascular risk prediction. Therefore, this review focuses on the pathomechanisms leading to HPV-related cardiovascular diseases with respect to atherosclerosis, and the description of potential novel biomarkers to detect the earliest atherosclerotic changes important for the prevention of CVD in HPV infection and cervical cancer.
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Affiliation(s)
- Ingrid Tonhajzerova
- Department of Physiology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak.
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak.
| | - Lucia B Olexova
- Department of Physiology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak
| | - Alexander Jurko
- Pediatric Cardiology Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak
| | - Bart Spronck
- Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, 6200 MD Maastricht, The Netherlands
| | - Tomas Jurko
- Neonatology Clinic, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, University Hospital Martin, 03601 Martin, Slovak
| | - Nikola Sekaninova
- Department of Physiology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak
| | - Zuzana Visnovcova
- Department of Physiology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak
| | - Andrea Mestanikova
- Department of Physiology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak
| | - Erik Kudela
- Gynaecology Clinic, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, University Hospital Martin, 03601 Martin, Slovak
| | - Michal Mestanik
- Department of Physiology, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak
- Biomedical Center Martin, Jessenius Faculty of Medicine in Martin, Comenius University in Bratislava, 03601 Martin, Slovak
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6
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Akinaga J, García‐Sáinz JA, S. Pupo A. Updates in the function and regulation of α 1 -adrenoceptors. Br J Pharmacol 2019; 176:2343-2357. [PMID: 30740663 PMCID: PMC6592863 DOI: 10.1111/bph.14617] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 12/19/2018] [Accepted: 01/21/2019] [Indexed: 12/16/2022] Open
Abstract
α1 -Adrenoceptors are seven transmembrane domain GPCRs involved in numerous physiological functions controlled by the endogenous catecholamines, noradrenaline and adrenaline, and targeted by drugs useful in therapeutics. Three separate genes, whose products are named α1A -, α1B -, and α1D - adrenoceptors, encode these receptors. Although the existence of multiple α1 -adrenoceptors has been acknowledged for almost 25 years, the specific functions regulated by each subtype are still largely unknown. Despite the limited comprehension, the identification of a single class of subtype-selective ligands for the α1A - adrenoceptors, the so-called α-blockers for prostate dysfunction, has led to major improvement in therapeutics, demonstrating the need for continued efforts in the field. This review article surveys the tissue distribution of the three α1 -adrenoceptor subtypes in the cardiovascular system, genitourinary system, and CNS, highlighting the functions already identified as mediated by the predominant activation of specific subtypes. In addition, this review covers the recent advances in the understanding of the molecular mechanisms involved in the regulation of each of the α1 -adrenoceptor subtypes by phosphorylation and interaction with proteins involved in their desensitization and internalization. LINKED ARTICLES: This article is part of a themed section on Adrenoceptors-New Roles for Old Players. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.14/issuetoc.
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Affiliation(s)
- Juliana Akinaga
- Department of PharmacologyInstituto de Biociências, UNESPBotucatuBrazil
| | - J. Adolfo García‐Sáinz
- Instituto de Fisiología CelularUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMexico
| | - André S. Pupo
- Department of PharmacologyInstituto de Biociências, UNESPBotucatuBrazil
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Raptis V, Loutradis C, Sarafidis PA. Renal injury progression in autosomal dominant polycystic kidney disease: a look beyond the cysts. Nephrol Dial Transplant 2018; 33:1887-1895. [DOI: 10.1093/ndt/gfy023] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
Affiliation(s)
- Vasileios Raptis
- Section of Nephrology and Hypertension, 1st Department of Medicine, AHEPA Hospital, Thessaloniki, Greece
| | - Charalampos Loutradis
- Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Pantelis A Sarafidis
- Department of Nephrology, Hippokration Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
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8
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Fonkoue IT, Marvar PJ, Norrholm SD, Kankam ML, Li Y, DaCosta D, Rothbaum BO, Park J. Acute effects of device-guided slow breathing on sympathetic nerve activity and baroreflex sensitivity in posttraumatic stress disorder. Am J Physiol Heart Circ Physiol 2018; 315:H141-H149. [PMID: 29652544 DOI: 10.1152/ajpheart.00098.2018] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Patients with posttraumatic stress disorder (PTSD) have elevated sympathetic nervous system reactivity and impaired sympathetic and cardiovagal baroreflex sensitivity (BRS). Device-guided slow breathing (DGB) has been shown to lower blood pressure (BP) and sympathetic activity in other patient populations. We hypothesized that DGB acutely lowers BP, heart rate (HR), and improves BRS in PTSD. In 23 prehypertensive veterans with PTSD, we measured continuous BP, ECG, and muscle sympathetic nerve activity (MSNA) at rest and during 15 min of DGB at 5 breaths/min ( n = 13) or identical sham device breathing at normal rates of 14 breaths/min (sham; n = 10). Sympathetic and cardiovagal BRS was quantified using pharmacological manipulation of BP via the modified Oxford technique at baseline and during the last 5 min of DGB or sham. There was a significant reduction in systolic BP (by -9 ± 2 mmHg, P < 0.001), diastolic BP (by -3 ± 1 mmHg, P = 0.019), mean arterial pressure (by -4 ± 1 mmHg, P = 0.002), and MSNA burst frequency (by -7.8 ± 2.1 bursts/min, P = 0.004) with DGB but no significant change in HR ( P > 0.05). Within the sham group, there was no significant change in diastolic BP, mean arterial pressure, HR, or MSNA burst frequency, but there was a small but significant decrease in systolic BP ( P = 0.034) and MSNA burst incidence ( P = 0.033). Sympathetic BRS increased significantly in the DGB group (-1.08 ± 0.25 to -2.29 ± 0.24 bursts·100 heart beats-1·mmHg-1, P = 0.014) but decreased in the sham group (-1.58 ± 0.34 to -0.82 ± 0.28 bursts·100 heart beats-1·mmHg-1, P = 0.025) (time × device, P = 0.001). There was no significant difference in the change in cardiovagal BRS between the groups (time × device, P = 0.496). DGB acutely lowers BP and MSNA and improves sympathetic but not cardiovagal BRS in prehypertensive veterans with PTSD. NEW & NOTEWORTHY Posttraumatic stress disorder is characterized by augmented sympathetic reactivity, impaired baroreflex sensitivity, and an increased risk for developing hypertension and cardiovascular disease. This is the first study to examine the potential beneficial effects of device-guided slow breathing on hemodynamics, sympathetic activity, and arterial baroreflex sensitivity in prehypertensive veterans with posttraumatic stress disorder.
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Affiliation(s)
- Ida T Fonkoue
- Division of Renal Medicine, Department of Medicine, Emory University School of Medicine , Atlanta, Georgia.,Research Service Line, Atlanta Veterans Affairs Medical Center, Decatur, Georgia
| | - Paul J Marvar
- Department of Pharmacology and Physiology, Institute for Neuroscience, George Washington University , Washington, District of Columbia
| | - Seth D Norrholm
- Mental Health Service Line, Atlanta Veterans Affairs Medical Center, Decatur, Georgia.,Psychiatry and Behavioral Sciences, Emory University , Atlanta, Georgia
| | - Melanie L Kankam
- Division of Renal Medicine, Department of Medicine, Emory University School of Medicine , Atlanta, Georgia.,Research Service Line, Atlanta Veterans Affairs Medical Center, Decatur, Georgia
| | - Yunxiao Li
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University , Atlanta, Georgia
| | - Dana DaCosta
- Division of Renal Medicine, Department of Medicine, Emory University School of Medicine , Atlanta, Georgia.,Research Service Line, Atlanta Veterans Affairs Medical Center, Decatur, Georgia
| | | | - Jeanie Park
- Division of Renal Medicine, Department of Medicine, Emory University School of Medicine , Atlanta, Georgia.,Research Service Line, Atlanta Veterans Affairs Medical Center, Decatur, Georgia
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9
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Park J, Marvar PJ, Liao P, Kankam ML, Norrholm SD, Downey RM, McCullough SA, Le NA, Rothbaum BO. Baroreflex dysfunction and augmented sympathetic nerve responses during mental stress in veterans with post-traumatic stress disorder. J Physiol 2017; 595:4893-4908. [PMID: 28503726 DOI: 10.1113/jp274269] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 04/12/2017] [Indexed: 12/13/2022] Open
Abstract
KEY POINTS Patients with post-traumatic stress disorder (PTSD) are at a significantly higher risk of developing hypertension and cardiovascular disease. The mechanisms underlying this increased risk are not known. Studies have suggested that PTSD patients have an overactive sympathetic nervous system (SNS) that could contribute to cardiovascular risk; however, sympathetic function has not previously been rigorously evaluated in PTSD patients. Using direct measurements of sympathetic nerve activity and pharmacological manipulation of blood pressure, we show that veterans with PTSD have augmented SNS and haemodynamic reactivity during both combat-related and non-combat related mental stress, impaired sympathetic and cardiovagal baroreflex sensitivity, and increased inflammation. Identifying the mechanisms contributing to increased cardiovascular (CV) risk in PTSD will pave the way for developing interventions to improve sympathetic function and reduce CV risk in these patients. ABSTRACT Post-traumatic stress disorder (PTSD) is associated with increased cardiovascular (CV) risk. We tested the hypothesis that PTSD patients have augmented sympathetic nervous system (SNS) and haemodynamic reactivity during mental stress, as well as impaired arterial baroreflex sensitivity (BRS). Fourteen otherwise healthy Veterans with combat-related PTSD were compared with 14 matched Controls without PTSD. Muscle sympathetic nerve activity (MSNA), continuous blood pressure (BP) and electrocardiography were measured at baseline, as well as during two types of mental stress: combat-related mental stress using virtual reality combat exposure (VRCE) and non-combat related stress using mental arithmetic (MA). A cold pressor test (CPT) was administered for comparison. BRS was tested using pharmacological manipulation of BP via the Modified Oxford technique at rest and during VRCE. Blood samples were analysed for inflammatory biomarkers. Baseline characteristics, MSNA and haemodynamics were similar between the groups. In PTSD vs. Controls, MSNA (+8.2 ± 1.0 vs. +1.2 ± 1.3 bursts min-1 , P < 0.001) and heart rate responses (+3.2 ± 1.1 vs. -2.3 ± 1.0 beats min-1 , P = 0.003) were significantly augmented during VRCE. Similarly, in PTSD vs. Controls, MSNA (+21.0 ± 2.6 vs. +6.7 ± 1.5 bursts min-1 , P < 0.001) and diastolic BP responses (+6.3 ± 1.0 vs. +3.5 ± 1.0 mmHg, P = 0.011) were significantly augmented during MA but not during CPT (P = not significant). In the PTSD group, sympathetic BRS (-1.2 ± 0.2 vs. -2.0 ± 0.3 burst incidence mmHg-1 , P = 0.026) and cardiovagal BRS (9.5 ± 1.4 vs. 23.6 ± 4.3 ms mmHg-1 , P = 0.008) were significantly blunted at rest. PTSD patients had significantly higher highly sensitive-C-reactive protein levels compared to Controls (2.1 ± 0.4 vs. 1.0 ± 0.3 mg L-1 , P = 0.047). Augmented SNS and haemodynamic responses to mental stress, blunted BRS and inflammation may contribute to an increased CV risk in PTSD.
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Affiliation(s)
- Jeanie Park
- Renal Division, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA.,Research Service Line, Atlanta VA Medical Center, Decatur, GA, USA
| | - Paul J Marvar
- Department of Pharmacology and Physiology, Institute for Neuroscience, George Washington University, Washington, DC, USA
| | - Peizhou Liao
- Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Melanie L Kankam
- Renal Division, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA.,Research Service Line, Atlanta VA Medical Center, Decatur, GA, USA
| | - Seth D Norrholm
- Mental Health Service Line, Atlanta VA Medical Center, Decatur, GA, USA.,Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA, USA
| | - Ryan M Downey
- Renal Division, Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA.,Research Service Line, Atlanta VA Medical Center, Decatur, GA, USA
| | - S Ashley McCullough
- Mental Health Service Line, Atlanta VA Medical Center, Decatur, GA, USA.,Psychiatry and Behavioral Sciences, Emory University, Atlanta, GA, USA
| | - Ngoc-Anh Le
- Biomarker Core Laboratory, Atlanta VA Medical Center, Decatur, GA, USA
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10
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Freitas FFCT, Araujo G, Porto ML, Freitas FPS, Graceli JB, Balarini CM, Vasquez EC, Meyrelles SS, Gava AL. Increased Blood Pressure Variability Prior to Chronic Kidney Disease Exacerbates Renal Dysfunction in Rats. Front Physiol 2016; 7:428. [PMID: 27721797 PMCID: PMC5034010 DOI: 10.3389/fphys.2016.00428] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 09/09/2016] [Indexed: 01/13/2023] Open
Abstract
Increased blood pressure variability (BPV), which can be experimentally induced by sinoaortic denervation (SAD), has emerged as a new marker of the prognosis of cardiovascular and renal outcomes. Considering that increased BPV can lead to organ-damage, the goal of the present study was to evaluate the effects of SAD on renal function in an experimental model of chronic kidney disease (CKD). SAD was performed in male Wistar rats 2 weeks before 5/6 nephrectomy and the animals were evaluated 4 weeks after the induction of CKD. Our data demonstrated that BPV was increased in SAD and CKD animals and that the combination of both conditions (SAD+CKD) exacerbated BPV. The baroreflex sensitivity index was diminished in the SAD and CKD groups; this reduction was more pronounced when SAD and CKD were performed together. 5/6 nephrectomy led to hypertension, which was higher in SAD+CKD animals. Regarding renal function, the combination of SAD and CKD resulted in reduced renal plasma and blood flow, increased renal vascular resistance and augmented uraemia when compared to CKD animals. Glomerular filtration rate and BPV were negatively correlated in SAD, CKD, and SAD+CKD animals. Moreover, SAD+CKD animals presented a higher level of glomerulosclerosis when compared to all other groups. Cardiac and renal hypertrophy, as well as oxidative stress, was also further increased when SAD and CKD were combined. These results show that SAD prior to 5/6 nephrectomy exacerbates renal dysfunction, suggesting that previous augmented BPV should be considered as an important factor to the progression of renal diseases.
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Affiliation(s)
- Frederico F C T Freitas
- Biotechnology Graduate Program, Health Sciences Center, Federal University of Espirito Santo Vitoria, Brazil
| | - Gilberto Araujo
- Biotechnology Graduate Program, Health Sciences Center, Federal University of Espirito Santo Vitoria, Brazil
| | - Marcella L Porto
- Physiological Sciences Graduate Program, Health Sciences Center, Federal University of Espirito Santo Vitoria, Brazil
| | - Flavia P S Freitas
- Physiological Sciences Graduate Program, Health Sciences Center, Federal University of Espirito Santo Vitoria, Brazil
| | - Jones B Graceli
- Morphology Department, Health Sciences Center, Federal University of Espirito Santo Vitoria, Brazil
| | - Camille M Balarini
- Department of Physiology and Pathology, Health Sciences Center, Federal University of Paraiba Joao Pessoa, Brazil
| | - Elisardo C Vasquez
- Physiological Sciences Graduate Program, Health Sciences Center, Federal University of Espirito SantoVitoria, Brazil; Pharmaceutical Sciences Graduate Program, University of Vila VelhaVila Velha, Brazil
| | - Silvana S Meyrelles
- Physiological Sciences Graduate Program, Health Sciences Center, Federal University of Espirito Santo Vitoria, Brazil
| | - Agata L Gava
- Physiological Sciences Graduate Program, Health Sciences Center, Federal University of Espirito SantoVitoria, Brazil; Division of Nephrology, McMaster UniversityHamilton, ON, Canada
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11
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Salman IM. Cardiovascular Autonomic Dysfunction in Chronic Kidney Disease: a Comprehensive Review. Curr Hypertens Rep 2016; 17:59. [PMID: 26071764 DOI: 10.1007/s11906-015-0571-z] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Cardiovascular autonomic dysfunction is a major complication of chronic kidney disease (CKD), likely contributing to the high incidence of cardiovascular mortality in this patient population. In addition to adrenergic overdrive in affected individuals, clinical and experimental evidence now strongly indicates the presence of impaired reflex control of both sympathetic and parasympathetic outflow to the heart and vasculature. Although the principal underlying mechanisms are not completely understood, potential involvements of altered baroreceptor, cardiopulmonary, and chemoreceptor reflex function, along with factors including but not limited to increased renin-angiotensin-aldosterone system activity, activation of the renal afferents and cardiovascular structural remodeling have been suggested. This review therefore analyzes potential mechanisms underpinning autonomic imbalance in CKD, covers results accumulated thus far on cardiovascular autonomic function studies in clinical and experimental renal failure, discusses the role of current interventional and therapeutic strategies in ameliorating autonomic deficits associated with chronic renal dysfunction, and identifies gaps in our knowledge of neural mechanisms driving cardiovascular disease in CKD.
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Affiliation(s)
- Ibrahim M Salman
- The Australian School of Advanced Medicine, Macquarie University, Sydney, New South Wales, Australia,
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12
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Shoemaker JK, Badrov MB, Al-Khazraji BK, Jackson DN. Neural Control of Vascular Function in Skeletal Muscle. Compr Physiol 2015; 6:303-29. [PMID: 26756634 DOI: 10.1002/cphy.c150004] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The sympathetic nervous system represents a fundamental homeostatic system that exerts considerable control over blood pressure and the distribution of blood flow. This process has been referred to as neurovascular control. Overall, the concept of neurovascular control includes the following elements: efferent postganglionic sympathetic nerve activity, neurotransmitter release, and the end organ response. Each of these elements reflects multiple levels of control that, in turn, affect complex patterns of change in vascular contractile state. Primarily, this review discusses several of these control layers that combine to produce the integrative physiology of reflex vascular control observed in skeletal muscle. Beginning with three reflexes that provide somewhat dissimilar vascular patterns of response despite similar changes in efferent sympathetic nerve activity, namely, the baroreflex, chemoreflex, and muscle metaboreflex, the article discusses the anatomical and physiological bases of postganglionic sympathetic discharge patterns and recruitment, neurotransmitter release and management, and details of regional variations of receptor density and responses within the microvascular bed. Challenges are addressed regarding the fundamentals of measurement and how conclusions from one response or vascular segment should not be used as an indication of neurovascular control as a generalized physiological dogma. Whereas the bulk of the article focuses on the vasoconstrictor function of sympathetic neurovascular integration, attention is also given to the issues of sympathetic vasodilation as well as the impact of chronic changes in sympathetic activation and innervation on vascular health. © 2016 American Physiological Society.
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Affiliation(s)
- J K Shoemaker
- School of Kinesiology, Western University, London, Ontario, Canada.,Department of Physiology and Pharmacology, Western University, London, Ontario, Canada
| | - M B Badrov
- School of Kinesiology, Western University, London, Ontario, Canada
| | - B K Al-Khazraji
- Department of Medical Biophysics, Western University, London, Ontario, Canada
| | - D N Jackson
- Department of Medical Biophysics, Western University, London, Ontario, Canada
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Relationship between muscle sympathetic nerve activity and aortic wave reflection characteristics in aerobic- and resistance-trained subjects. Eur J Appl Physiol 2015; 115:2609-19. [DOI: 10.1007/s00421-015-3230-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 07/29/2015] [Indexed: 12/26/2022]
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Mao Y, Su J, Lei L, Meng L, Qi Y, Huo Y, Tang C. Impaired regulator of G protein signaling 2 transcription facilitates vascular remodeling in injured rat aorta. J Cardiovasc Med (Hagerstown) 2015; 15:572-8. [PMID: 24914635 DOI: 10.2459/jcm.0b013e3283629c30] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND The activation of Gq-protein-coupled receptors induces proliferation of vascular smooth muscle cells (VSMCs) proliferation and is involved in vascular remodeling. The regulator of G protein signaling 2 (RGS2), which accelerates the termination of Gq protein signaling, may play a role in vascular remodeling. However, this role remains unclear. METHODS Aortic balloon injury or sham operation was produced in male Wistar rats. Histological examination and gene expression analysis were performed after surgery. In cultured VSMCs after modulation of RGS2 expression, cell proliferation was also evaluated. RESULTS At day 3 after injury, RGS2 transcription was reduced by 52.8% (P <0.05 vs. sham group) with vascular remodeling. In cultured VSMCs stimulated by endothelin-1, phenylephrine or angiotensin II, the proliferation of RGS2 overexpressed cells was significantly inhibited; the proliferation of RGS2 downregulated cells was significantly promoted, compared with that of RGS2 normal cells. Moreover, after incubation with angiotensin II of high concentration (>10 μmol/l) or long term (>8 h), the RGS2 expression was clearly downregulated in cultured VSMCs. Administration of an angiotensin receptor blocker, valsartan (20 mg/kg per day) starting from 1 week preballoon injury to 3 days after injury, restored aortic RGS2 transcription and improved vascular remodeling. CONCLUSION These results suggested that the inhibiting effect of RGS2 on VSMC proliferation is downregulated in vascular remodeling of injured rat aorta, and this effect is likely to be mediated by angiotensin II signaling.
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Affiliation(s)
- Yuanjie Mao
- aDepartment of Cardiology, Peking University First Hospital, Beijing, China bDepartment of Biochemistry, National Cerebral and Cardiovascular Center, Osaka, Japan cCardiology Division, Cardiovascular Research Center, Rhode Island Hospital and Alpert Medical School of Brown University, Providence, Rhode Island, USA dDepartment of Endocrinology, Beijing Aerospace Center Hospital eDepartment of Physiology, School of Basic Medical Sciences, Peking University, Beijing, China
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15
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Yasunari E, Mita T, Osonoi Y, Azuma K, Goto H, Ohmura C, Kanazawa A, Kawamori R, Fujitani Y, Watada H. Repetitive hypoglycemia increases circulating adrenaline level with resultant worsening of intimal thickening after vascular injury in male Goto-Kakizaki rat carotid artery. Endocrinology 2014; 155:2244-53. [PMID: 24684300 DOI: 10.1210/en.2013-1628] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Hypoglycemia associated with diabetes management is a potential risk for cardiovascular diseases. However, the effect of hypoglycemic episodes including a surge of sympathetic activity on the progression of neointima formation after vascular injury remains largely unknown. In this study, insulin was injected intraperitoneally into nonobese diabetic Goto-Kakizaki (GK) rats, once every 3 days for 4 weeks after balloon injury of carotid artery to induce hypoglycemia. Then, we evaluated balloon injury-induced neointima formation. Insulin treatment enhanced neointima formation and increased the number of proliferating cell nuclear antigen (PCNA)-positive cells in the carotid artery. Injection of glucose with insulin prevented hypoglycemia and abrogated intimal thickening. Also, bunazosin, an α1 adrenergic receptor antagonist, prevented intimal thickening and accumulation of PCNA-positive cells induced by insulin treatment despite the presence of concomitant hypoglycemia and high adrenaline levels. Incubation of cultured smooth muscle cells with adrenaline resulted in a significant increase in their proliferation and G0/G1 to S phase progression, which was associated with activation of extracellular signal-regulated kinase, enhanced expression of cell cycle regulatory molecules such as cyclin D1, and cyclin E, and phosphorylation of retinoblastoma protein. These adrenaline-induced effects were abrogated by bunazosin. Our data indicated that increased adrenaline induced by repetitive hypoglycemia promotes intimal thickening and smooth muscle cell proliferation after endothelial denudation in GK rats.
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Affiliation(s)
- Eisuke Yasunari
- Department of Metabolism & Endocrinology (E.Y., T.M., Y.O., K.A., H.G., C.O., A.K., Y.H., H.W.), Center for Molecular Diabetology (T.M., H.W), Sportology Center (R.K., H.W.), Center for Therapeutic Innovations in Diabetes (H.W.), Center for Beta Cell Biology and Regeneration (Y.F., H.W.), Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
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16
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Dopp JM, Agapitov AV, Sinkey CA, Haynes WG, Phillips BG. Sildenafil increases sympathetically mediated vascular tone in humans. Am J Hypertens 2013; 26:762-9. [PMID: 23443723 DOI: 10.1093/ajh/hpt018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Sildenafil, a selective phosphodiesterase-type-5 (PDE-5) inhibitor, produces vasodilation that improves erectile dysfunction and pulmonary hypertension. Sildenafil could also cause baroreflex sympathetic activation that would enhance vascular tone and oppose direct vasodilation. We tested the hypothesis that sildenafil administration increases sympathetically mediated vascular tone in healthy middle-aged men. METHODS We randomized 9 healthy, middle-aged, male volunteers (mean age 45±2 years) in a double-blind, crossover fashion to receive a single oral dose of sildenafil 100mg or placebo on 2 separate study days. Hemodynamics and forearm blood flow responses were measured at baseline, at 30 and 45 minutes after study drug administration, and then during intra-arterial infusions of vasoactive drugs. After sildenafil and placebo administration, intrabrachial medications were infused to test forearm alpha receptor sensitivity (norepinephrine), cyclic-AMP-mediated vasodilation (isoproterenol), and sympathetically mediated vascular tone (phentolamine) (adenosine was a control vasodilator). Blood samples were taken before and 60 minutes after study drug administration and at the end of the intrabrachial infusions for measurement of plasma norepinephrine concentrations. RESULTS Forearm vascular responses to norepinephrine, isoproterenol, and adenosine were not different after placebo and sildenafil administration. Percentage reduction in forearm vascular resistance during phentolamine was significantly lower after sildenafil than placebo (-73% ± 3% vs -63% ± 3%; P = 0.0002). Sildenafil significantly increased plasma norepinephrine compared with placebo 60 minutes after study drug administration and at the end of the study session (P = 0.02). CONCLUSIONS Sildenafil increased sympathetically mediated vascular tone in middle-aged healthy men. Alpha-adrenergic-mediated vasoconstriction may offset vasodilation during PDE-5 inhibition and may explain the significant hypotension observed in patients taking alpha-blockers with sildenafil.
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Affiliation(s)
- John M Dopp
- Pharmacy Practice Division, School of Pharmacy, University of Wisconsin-Madison, Madison, Wisconsin, USA.
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Zhang HG, Cheng YQ, Liu Y, Zhou JZ, Jia Y, Wang XQ, Li XH. Gαq-protein carboxyl terminus imitation polypeptide GCIP-27 attenuates proliferation of vascular smooth muscle cells and vascular remodeling in spontaneously hypertensive rats. Biol Pharm Bull 2012; 34:1527-32. [PMID: 21963491 DOI: 10.1248/bpb.34.1527] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Gq-protein is located at the convergent point in signal transduction pathways leading to vascular remodeling. The carboxyl terminus of Gα-subunit plays a vital role in G-protein-receptor interaction. The present study was designed to explore the effects of a synthetic Gαq carboxyl terminus imitation peptide, namely GCIP-27, on vascular smooth muscle cells (VSMC) in vitro and vascular remodeling in spontaneous hypertensive rats (SHR). Hyperplasia and hypertrophy of VSMC wre determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, [(3)H]-thymidine and [(3)H]-leucine incorporation, and [Ca(2+)](i) was measured with Fluo-3/AM staining. Systolic blood pressure (SBP), the ratio of media thickness to lumen diameter (MT/LD) of aorta, collagen content, and phospholipase C activity in aorta were measured in SHR. GCIP-27 (3-100 µg/l) significantly decreased proliferation activity, protein content, incorporation of [(3)H]-thymidine and [(3)H]-leucine, and [Ca(2+)](i) level in VSMC. SBP, MT/LD, collagen content, and phospholipase C activity in aorta of SHR were decreased significantly in GCIP-27 (7, 20, 60 µg/kg)-treated groups and losartan (6 mg/kg) group compared with vehicle group. In conclusion, GCIP-27 could inhibit vascular remodeling effectively in vitro and in vivo.
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Affiliation(s)
- Hai-Gang Zhang
- Institute of Materia Medica and Department of Pharmaceutics, College of Pharmacy, Third Military Medical University, P.R. China
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Camici M, Carpi A, Cini G, Galetta F, Abraham N. Podocyte dysfunction in aging--related glomerulosclerosis. Front Biosci (Schol Ed) 2011; 3:995-1006. [PMID: 21622249 DOI: 10.2741/204] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
We review podocyte molecular structure and function, consider the underlying mechanisms related to podocyte dysfunction and propose that podocyte dysfunction be considered in the evaluation and management of age-associated glomerulosclerosis. With aging, progressive sympathetic activation, increased intrarenal renin-angiotensin system (RAS) activity, endothelin system and oxidative stress and reduced nitric oxide (NO)-availability can damage podocytes. Apoptosis and proliferation are the principal podocyte changes following injury with the latter leading to sclerosis and loss of nephrons. Podocyte loss can be evaluated by either determining their average number in biopsed glomeruli or by estimating podocyte number or their associated molecules in urine sediment. Podocyturia may be considered a marker of active glomerular disease. Preliminary data suggest that antiadrenergic drugs, angiotensin converting enzyme (ACE) inhibitors, RAS blocking drugs, endothelin system inhibitors and reduced oxidative stress can protect podocytes. Thus podocytes appear to play an important role in the pathogenesis, evaluation and therapy of age related glomerulosclerosis.
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Affiliation(s)
- Marcello Camici
- Department of Internal Medicine, Pisa University, Pisa, Italy
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Ryabikov A, Malyutina S, Halcox J, Nikitin Y, Marmot M, Bobak M. Prevalence and predictors of carotid wall triple line pattern in a general population sample. Arterioscler Thromb Vasc Biol 2011; 31:1682-8. [PMID: 21493889 DOI: 10.1161/atvbaha.110.218057] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Carotid intima-media thickness (IMT) and plaques are markers of atherosclerosis and predict cardiovascular events. A specific sonographic triple line pattern (TLP) of the carotid wall has been identified in different conditions, but its origin and clinical significance are unclear. We examined the prevalence and predictors of TLP in a general population. METHODS AND RESULTS The study was conducted in random sample of the general population of Novosibirsk, Russia, within the international Health, Alcohol and Psychosocial Factors in Eastern Europe project. In a subsample of 418 men (aged 45 to 69), carotid IMT, the presence of atherosclerotic plaques, and the presence of TLP were assessed by ultrasound. The prevalence of TLP was 21%. It was associated with IMT (odds ratio = 9.53 per 1 SD, P<0.001) and the presence of plaques (odds ratio = 2.42, P = 0.002). Other predictors of TLP in multivariate models included age, systolic blood pressure, total cholesterol, and smoking. In addition, infrequent consumption of high amounts of alcohol approximately doubled the risk of triple pattern. CONCLUSIONS Our findings showed high prevalence of TLP of carotid wall in a general male population sample from a typical Russian city. This sonographic pattern was strongly associated with cardiovascular risk factors and diseases, bioimaging indicators of atherosclerosis, and episodic heavy drinking.
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Affiliation(s)
- Andrew Ryabikov
- Laboratory of Internal Medicine, Institute of Internal Medicine Siberian Branch of the Russian Academy of Medical Sciences, Novosibirsk, Russia.
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Casey DP, Curry TB, Joyner MJ, Charkoudian N, Hart EC. Relationship between muscle sympathetic nerve activity and aortic wave reflection characteristics in young men and women. Hypertension 2011; 57:421-7. [PMID: 21242459 DOI: 10.1161/hypertensionaha.110.164517] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Increased arterial stiffness is associated with higher levels of aortic wave reflection and aortic blood pressure. Recent evidence suggests a link between muscle sympathetic nerve activity and indices of arterial stiffness. Therefore, the aims of this study were to examine the relationship between resting muscle sympathetic nerve activity and characteristics of aortic pressure wave reflection and the influence of sex on these relationships. In 44 subjects (23 females and 21 males; 25 ± 1 years of age), we measured muscle sympathetic nerve activity via peroneal microneurography. In addition, noninvasive aortic pressure waveforms were synthesized from radial pressure waveforms obtained from applanation tonometry. Aortic blood pressure, augmentation index, wave reflection amplitude, and wasted left ventricular energy were calculated. Resting sympathetic activity (bursts/100 heart beats) was not associated with any of the aortic pressure wave reflection characteristics for all patients. However, there was a positive relationship between sympathetic activity and augmentation index (r = 0.46; P = 0.05) in men. Further, sympathetic activity in men was related to wave reflection amplitude (r = 0.53; P<0.05) and wasted left ventricular energy (r = 0.57; P<0.01). In contrast to men, women demonstrated strong inverse relationships between sympathetic activity and augmentation index (r = -0.63), wave reflection amplitude ( r = -0.59), and wasted left ventricular energy (r = -0.58; P<0.01 for all). Our results suggest another possible mechanism by which young women are protected against the development of cardiovascular disease.
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Affiliation(s)
- Darren P Casey
- Department of Anesthesiology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA.
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The role of sympathetic nervous activity in renal injury and end-stage renal disease. Hypertens Res 2010; 33:521-8. [DOI: 10.1038/hr.2010.35] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Galetta F, Franzoni F, Bernini G, Poupak F, Carpi A, Cini G, Tocchini L, Antonelli A, Santoro G. Cardiovascular complications in patients with pheochromocytoma: a mini-review. Biomed Pharmacother 2009; 64:505-9. [PMID: 20580187 DOI: 10.1016/j.biopha.2009.09.014] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Accepted: 09/24/2009] [Indexed: 01/14/2023] Open
Abstract
Phaeochromocytomas are rare neuroendocrine tumours secreting high levels of catecholamines, able to exert serious metabolic and cardiovascular effects. The serious and potentially lethal cardiovascular complications of these tumours are due to the potent effects of secreted catecholamines, especially noradrenaline, the main transmitter released from sympathetic nerve terminals. Hypertension, tachycardia, pallor, headache and anxiety, usually dominate the clinical presentation. Occasionally, patients with predominantly epinephrine-secreting tumours present hypotension or even shock. Other cardiovascular complications of pheochromocytoma include ischaemic heart disease, acute myocardial infarction, cardiac arrhythmias, heart failure due to toxic cardiomyopathy, or pulmonary edema. Catecholamines have been shown to influence the extracellular matrix with collagen deposition and subsequent fibrosis in the arterial wall and in the myocardium. These morphofunctional changes of the myocardium and of arterial wall can be emphasized by ultrasound imaging. Indeed, ultrasound imaging of the myocardium and arterial wall not only identifies wall thickness but also contains information on texture that may be revealed by acoustic tissue characterization. The latter can be quantified through videodensitometric analysis of echographic images or through ultrasonic integrated backscatter signal analysis. This paper reviews cardiovascular complications in patients with pheochromocytoma and utility of the new ultrasound technique as backscatter signal. It is useful for evaluating preclinical pathological morphofunctional changes of the myocardium and arterial wall, characterized by increased collagen content in pheochromocytoma patients. The recognition of early catecholamine-induced alterations in patients with pheochromocytoma, is important to prevent at least morbidity and mortality, before surgical treatment.
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Affiliation(s)
- Fabio Galetta
- Department of Internal Medicine, University of Pisa, Pisa, Italy
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Tsoporis JN, Overgaard CB, Izhar S, Parker TG. S100B modulates the hemodynamic response to norepinephrine stimulation. Am J Hypertens 2009; 22:1048-53. [PMID: 19713945 DOI: 10.1038/ajh.2009.145] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND We have previously reported that S100B acts as an intrinsic negative regulator of the myocardial hypertrophic response to norepinephrine (NE). METHODS To examine the role of S100B in acute and chronic hemodynamic responses to NE stimulation, knockout (KO) mice devoid of the S100B gene, transgenic (TG) mice with forced overexpression of S100B, and control CD1 mice were injected subcutaneously once daily with NE (1.5 mg/kg) or vehicle for 28 days. RESULTS The acute and chronic hemodynamic responses were not different in CD1 and TG mice. In KO mice, both the chronic and acute increase in blood pressure (BP) in response to NE was attenuated compared with CD1 mice. NE induced ventricular myocyte hypertrophy and smooth muscle proliferation in CD1 mice, responses that were augmented in KO mice. In TG mice, NE did not induce myocyte hypertrophy or smooth muscle cell proliferation. NE treatment of smooth muscle cells derived from KO mice resulted in lower cytosolic calcium concentrations compared to CD1 and TG mice. NE induced S100B in ventricular myocytes and increased S100B in arterial tissues of CD1 and TG mice. The giant phosphoprotein AHNAK is expressed in both ventricular myocytes and aortic smooth muscle cells (ASMCs). In response to NE, S100B co-immunoprecipitates with AHNAK in ventricular myocytes and ASMCs. CONCLUSION Thus, absence of S100B is associated with attenuation of the hemodynamic response to catecholamines, in contradistinction to, the augmented cardiac hypertrophy and smooth muscle cell proliferation.
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Hodges GJ, Jackson DN, Mattar L, Johnson JM, Shoemaker JK. Neuropeptide Y and neurovascular control in skeletal muscle and skin. Am J Physiol Regul Integr Comp Physiol 2009; 297:R546-55. [PMID: 19571208 DOI: 10.1152/ajpregu.00157.2009] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Neuropeptide Y (NPY) is a ubiquitous peptide with multiple effects on energy metabolism, reproduction, neurogenesis, and emotion. In addition, NPY is an important sympathetic neurotransmitter involved in neurovascular regulation. Although early studies suggested that the vasoactive effects of NPY were limited to periods of high stress, there is growing evidence for the involvement of NPY on baseline vasomotor tone and sympathetically evoked vasoconstriction in vivo in both skeletal muscle and the cutaneous circulation. In Sprague-Dawley rat skeletal muscle, Y(1)-receptor activation appears to play an important role in the regulation of basal vascular conductance, and this effect is similar in magnitude to the alpha(1)-receptor contribution. Furthermore, under baseline conditions, agonist and receptor-based mechanisms for Y(1)-receptor-dependent control of vascular conductance in skeletal muscle are greater in male than female rats. In skin, there is Y(1)-receptor-mediated vasoconstriction during whole body, but not local, cooling. As with the NPY system in muscle, this neural effect in skin differs between males and females and in addition, declines with aging. Intriguingly, skin vasodilation to local heating also requires NPY and is currently thought to be acting via a nitric oxide pathway. These studies are establishing further interest in the role of NPY as an important vasoactive agent in muscle and skin, adding to the complexity of neurovascular regulation in these tissues. In this review, we focus on the role of NPY on baseline vasomotor tone in skeletal muscle and skin and how NPY modulates vasomotor tone in response to stress, with the aim of compiling what is currently known, while highlighting some of the more pertinent questions yet to be answered.
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Affiliation(s)
- Gary J Hodges
- School of Kinesiology, University of Western Ontario, London, Ontario.
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Leyva-Jiménez R, Rodríguez-Orozco AR, Ortega-Pierres LE, Ramírez-Enríquez J, Gómez-García A, Alvarez-Aguilar C. [Effect of pentoxifylline on the evolution of diabetic nephropathy]. Med Clin (Barc) 2009; 132:772-8. [PMID: 19464709 DOI: 10.1016/j.medcli.2008.05.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2007] [Accepted: 05/07/2008] [Indexed: 02/09/2023]
Abstract
BACKGROUND AND OBJECTIVE Diabetic nephropathy (DN) is the principal cause of end-chronic kidney disease. Metabolic and hemodynamic components are directly involved. However, convincing data have shown that inflammation participates in the diabetic complications. The aim of this study was to investigate whether the inhibition of the inflammation and pro-inflammatory cytokines with pentoxifylline (PXF) attenuate the progression of the DN. SUBJECTS AND METHOD In a prospective, randomized, double-blind, placebo- controlled study, we evaluated the effect of PXF (1200 mg daily) during 12 months, in 34 patients with incipient or established DN. Evaluated parameters were inflammation, pro-inflammatory cytokines and urinary albumin excretion (UAE). RESULTS PXF treatment had a reno-protective effect determined by a significant reduction in the UAE in both incipient and established (p<0,01) DN patient. This effect was attributed to a reduction in the C-reactive protein, interleukin-6, tumor necrosis factor-alpha and leptin serum levels (p<0,01). CONCLUSIONS PXF treatment caused regression and prevented the progression of renal damage. Thus, PXF should be used in the preventive treatment of DN. These results showed that inflammation and pro-inflammatory cytokines are related to the progression of diabetic nephropathy.
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Affiliation(s)
- Rafael Leyva-Jiménez
- Unidad de Investigación en Epidemiología Clínica, Hospital General Regional No. 1 (HGR No. 1), Instituto Mexicano de Seguro Social (IMSS). Morelia, Michoacán, México
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Ruohonen ST, Abe K, Kero M, Toukola L, Ruohonen S, Röyttä M, Koulu M, Pesonen U, Zukowska Z, Savontaus E. Sympathetic nervous system-targeted neuropeptide Y overexpression in mice enhances neointimal formation in response to vascular injury. Peptides 2009; 30:715-20. [PMID: 19135490 PMCID: PMC2914533 DOI: 10.1016/j.peptides.2008.12.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2008] [Revised: 12/08/2008] [Accepted: 12/08/2008] [Indexed: 11/21/2022]
Abstract
Sympathetic neurotransmitter neuropeptide Y (NPY) is associated with vascular remodelling, neointimal hyperplasia and atherosclerosis in experimental animal models and clinical studies. In order to study the role of sympathetic nerve-produced NPY in vascular diseases, transgenic mouse model overexpressing NPY in central and peripheral noradrenergic neurons under the dopamine-beta-hydroxylase (DBH) promoter was recently created (OE-NPY(DBH) mouse). This study aimed to examine the effect of NPY overexpression on arterial neointimal hyperplasia in an experimental model of vascular injury. Transgenic OE-NPY(DBH) mice and wildtype control mice of two different inbred strains (C57BL/6 and FVB/n) underwent a femoral artery surgery with a transluminar injury by a 0.38-mm guide wire insertion. Arteries were harvested 4 weeks from the surgery, and they were stained for basic morphology. Both strains of OE-NPY(DBH) mice, as compared with wildtype control mice, showed on average 50% greater formation of the neointima (P<0.01) and an increase in the medial area (P=0.05). The results suggest that moderately increased neuronal NPY causes the arteries to be more susceptible to femoral artery thickening after endothelial injury. The OE-NPY(DBH) mouse provides a novel tool to explore the role of NPY in the development of vascular disease related to metabolic disorders.
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Affiliation(s)
- Suvi T. Ruohonen
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Finland
- Department of Physiology, Biophysics and Neurosciences, Georgetown University Medical Center, Washington, DC, USA
- Drug Discovery Graduate School, University of Turku, Finland
| | - Ken Abe
- Department of Physiology, Biophysics and Neurosciences, Georgetown University Medical Center, Washington, DC, USA
| | - Mia Kero
- Department of Pathology, University of Turku, Finland
| | - Laura Toukola
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Finland
| | - Saku Ruohonen
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Finland
| | - Matias Röyttä
- Department of Pathology, University of Turku, Finland
| | - Markku Koulu
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Finland
| | - Ullamari Pesonen
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Finland
| | - Zofia Zukowska
- Department of Physiology, Biophysics and Neurosciences, Georgetown University Medical Center, Washington, DC, USA
| | - Eriika Savontaus
- Department of Pharmacology, Drug Development and Therapeutics, University of Turku, Finland
- Clinical Pharmacology, TYKSLAB, Health Care District of Southwest Finland, Finland
- Corresponding author at: Department of Pharmacology, Drug Development and Therapeutics, University of Turku, FIN-20014 Turku, Finland. Tel.: +358 2 3337362; fax: +358 2 3337216
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Kopp W. Chronically increased activity of the sympathetic nervous system: our diet-related "evolutionary" inheritance. J Nutr Health Aging 2009; 13:27-9. [PMID: 19151904 DOI: 10.1007/s12603-009-0005-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE It is well established that an increased activity of the sympathetic nervous system (SNS) plays an important role in the pathogenesis of cardiovascular disease (CVD), like essential hypertension, atherosclerosis and age related arterial wall thickening, heart failure, and ventricular arrhythmias. It is also well established that SNS activity is influenced by food ingestion, and that diet composition plays an important role: Among dietary substrates, carbohydrate (starch and sugars) ingestion significantly increases SNS activity, while protein or fat ingestion has no significant sympathoexcitory effect. The aim of this paper is to investigate the possibility that significant dietary changes during human evolution, i. e. the introduction of starch and sugars into human nutrition, have brought about a deleterious effect: an abnormal, chronically increased activity of the sympathetic nervous system (SNS). METHOD Literature search using MEDLINE to identify publications on the relationship of SNS activity and cardiovascular disease on the one hand and dietary substrates on the other hand. CONCLUSION The introduction of starchy food and sugars has brought about a new metabolic problem: a diet-related chronically increased SNS activity, with adverse effect on human health.
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Affiliation(s)
- W Kopp
- Diagnostikzentrum Graz, Graz, Austria.
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Holaj R, Zelinka T, Wichterle D, Petrák O, Štrauch B, Vránková A, Majtan B, Spáčil J, Malik J, Widimský J. Increased carotid intima-media thickness in patients with pheochromocytoma in comparison to essential hypertension. J Hum Hypertens 2008; 23:350-8. [DOI: 10.1038/jhh.2008.130] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Schlaich MP, Socratous F, Hennebry S, Eikelis N, Lambert EA, Straznicky N, Esler MD, Lambert GW. Sympathetic activation in chronic renal failure. J Am Soc Nephrol 2008; 20:933-9. [PMID: 18799718 DOI: 10.1681/asn.2008040402] [Citation(s) in RCA: 304] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The potential involvement of sympathetic overactivity has been neglected in this population despite accumulating experimental and clinical evidence suggesting a crucial role of sympathetic activation for both progression of renal failure and the high rate of cardiovascular events in patients with chronic kidney disease. The contribution of sympathetic neural mechanisms to the occurrence of cardiac arrhythmias, the development of hypertension, and the progression of heart failure are well established; however, the exact mechanisms contributing to heightened sympathetic tone in patients with chronic kidney disease are unclear. This review analyses potential mechanisms underlying sympathetic activation in chronic kidney disease, the range of adverse consequences associated with this activation, and potential therapeutic implications resulting from this relationship.
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Affiliation(s)
- Markus P Schlaich
- Neurovascular Hypertension & Kidney Disease Laboratory, Baker Heart Research Institute, P.O. Box 6492 St. Kilda Road Central, Melbourne VIC 8008, Australia.
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Isoeugenodilol inhibits smooth muscle cell proliferation and neointimal thickening after balloon injury via inactivation of ERK1/2 pathway. J Biomed Sci 2008; 15:375-89. [DOI: 10.1007/s11373-008-9236-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2007] [Accepted: 01/14/2008] [Indexed: 10/22/2022] Open
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Martinez-Lemus LA. Persistent Agonist-Induced Vasoconstriction Is Not Required for Angiotensin II to Mediate Inward Remodeling of Isolated Arterioles with Myogenic Tone. J Vasc Res 2007; 45:211-21. [DOI: 10.1159/000112513] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2007] [Accepted: 09/21/2007] [Indexed: 11/19/2022] Open
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Tsagalis G, Zerefos S, Zerefos N. Cardiorenal syndrome at different stages of chronic kidney disease. Int J Artif Organs 2007; 30:564-76. [PMID: 17674332 DOI: 10.1177/039139880703000703] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The central concept of the cardiorenal syndrome (CRS) is that the heart and the kidney should be regarded not solely as individual organs but rather as a dipole with multiple interconnections. The interplay between the heart and the kidney seems complex and multifactorial: cardiac output, regulation of extracellular volume, blood pressure and renal sodium handling are the major parameters that determine the crosstalk between the 2 organs. These basic parameters are controlled through mediators (renin-angiotensin system, endothelin) and the relevant antagonists (natriuretic peptides). Recently, it has been shown that the nitric oxide / reactive oxygen species balance, sympathetic nervous system activation and the presence of systemic inflammation aggravate atherosclerosis, promote structural alterations in left ventricular geometry and favor progression of renal disease. Although the prevalence of the CRS is high, major clinical trials for heart failure have only partially addressed this issue. The present review tries to dissect the role of various components of the CRS in a way that could potentially facilitate the implementation of specific therapeutic strategies. The multiple factors that participate in the pathogenesis of this syndrome are studied in detail in an effort to better understand this syndrome and address effectively its various components, since a holistic approach could (ideally) alter the syndrome's course and hence ameliorate the prognosis of the CRS.
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Affiliation(s)
- G Tsagalis
- Renal Unit, Ygia Hospital, Athens, Greece.
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35
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Harris DM, Cohn HI, Pesant S, Zhou RH, Eckhart AD. Vascular smooth muscle Gqsignaling is involved in high blood pressure in both induced renal and genetic vascular smooth muscle-derived models of hypertension. Am J Physiol Heart Circ Physiol 2007; 293:H3072-9. [PMID: 17873012 DOI: 10.1152/ajpheart.00880.2007] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
More than 30% of the US population has high blood pressure (BP), and less than a third of people treated for hypertension have it controlled. In addition, the etiology of most high BP is not known. Having a better understanding of the mechanisms underlying hypertension could potentially increase the effectiveness of treatment. Because Gqsignaling mediates vasoconstriction and vascular function can cause BP abnormalities, we were interested in determining the role of vascular smooth muscle (VSM) Gqsignaling in two divergent models of hypertension: a renovascular model of hypertension through renal artery stenosis and a genetic model of hypertension using mice with VSM-derived high BP. Inhibition of VSM Gqsignaling attenuated BP increases induced by renal artery stenosis to a similar extent as losartan, an ANG II receptor blocker and current antihypertensive therapy. Inhibition of Gqsignaling also attenuated high BP in our genetic VSM-derived hypertensive model. In contrast, BP remained elevated 25% following treatment with losartan, and prazosin, an α1-adrenergic receptor antagonist, only decreased BP by 35%. Inhibition of Gqsignaling attenuated VSM reactivity to ANG II and resulted in a 2.4-fold rightward shift in EC50. We also determined that inhibition of Gqsignaling was able to reverse VSM hypertrophy in the genetic VSM-derived hypertensive model. These results suggest that Gqsignaling is an important signaling pathway in two divergent models of hypertension and, perhaps, optimization of antihypertensive therapy could occur with the identification of particular Gq-coupled receptors involved.
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Affiliation(s)
- David M Harris
- Eugene Feiner Laboratory of Vascular Biology and Thrombosis, Center for Translational Medicine, Thomas Jefferson University, Philadelphia, PA, USA
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36
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Masuo K, Katsuya T, Sugimoto K, Kawaguchi H, Rakugi H, Ogihara T, Tuck ML. High plasma norepinephrine levels associated with beta2-adrenoceptor polymorphisms predict future renal damage in nonobese normotensive individuals. Hypertens Res 2007; 30:503-11. [PMID: 17664853 DOI: 10.1291/hypres.30.503] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Renal injury is common in obesity and hypertension. In the present study, we examined relationships between renal function alterations, plasma norepinephrine (NE), and beta2-adrenoceptor polymorphisms in a longitudinal design over 5 years. In 219 nonobese, normotensive men with entry-normal renal function, we measured serum blood urea nitrogen (BUN), creatinine, creatinine clearance, plasma NE, homeostasis model assessment of insulin resistance (HOMA-IR), body mass index (BMI), total body fat mass, and blood pressure (BP) annually for 5 years. beta2 (Arg16Gly, Gln27Glu)-adrenoceptor polymorphisms were determined. The subjects were stable in body weight and BP (<10%) for 5 years. High plasma NE was defined as > or =mean+1 SD at entry. Thirty-seven subjects had entry-high plasma NE and 182 were entry-normal. Entry-high plasma NE subjects had significantly greater total body fat mass and plasma NE and significantly lower creatinine clearance at entry and throughout the study. Increases in BMI, fat mass, BP, plasma NE, BUN, and creatinine, as well as the reduction in creatinine clearance in the 5 years, were significantly greater in entry-high NE subjects. These subjects had significantly higher frequencies of the Gly16 allele of beta2-adrenoceptor polymorphisms. Throughout the study, subjects carrying the Gly16 allele had higher plasma NE, HOMA-IR, and fat mass, and significantly greater reductions in creatinine clearance. Plasma NE at entry was a determinant variable for changes in BUN, creatinine, and creatinine clearance over the 5-year period in multiple regression analysis. In conclusion, high plasma NE at entry, associated with the Gly16 allele of the beta2-adrenoceptor polymorphisms, predict renal function deterioration (seen in elevations of BUN and creatinine and reduction of creatinine clearance) over a 5-year period accompanying further heightened sympathetic nerve activity and deterioration of insulin resistance.
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Affiliation(s)
- Kazuko Masuo
- Human Neurotransmitter Laboratory, Baker Heart Research Institute, Melbourne, Australia.
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Hosoda C, Hiroyama M, Sanbe A, Birumachi JI, Kitamura T, Cotecchia S, Simpson PC, Tsujimoto G, Tanoue A. Blockade of both α1A- and α1B-adrenergic receptor subtype signaling is required to inhibit neointimal formation in the mouse femoral artery. Am J Physiol Heart Circ Physiol 2007; 293:H514-9. [PMID: 17384126 DOI: 10.1152/ajpheart.00626.2006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Attenuation of early restenosis after percutaneous coronary intervention (PCI) is important for the successful treatment of coronary artery disease. Some clinical studies have shown that hypertension is a risk factor for early restenosis after PCI. These findings suggest that α1-adrenergic receptors (α1-ARs) may facilitate restenosis after PCI because of α1-AR's remarkable contribution to the onset of hypertension. In this study, we examined the neointimal formation after vascular injury in the femoral artery of α1A-knockout (α1A-KO), α1B-KO, α1D-KO, α1A-/α1B-AR double-KO (α1AB-KO), and wild-type mice to investigate the functional role of each α1-AR subtype in neointimal formation, which is known to promote restenosis. Neointimal formation 4 wk after wire injury was significantly ( P < 0.05) smaller in α1AB-KO mice than in any other group of mice, while blood pressures were not altered in any of the groups of mice after wire injury compared with those before it. These results suggest that lack of both α1A- and α1B-ARs could be necessary to inhibit neointimal formation in the mouse femoral artery.
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Affiliation(s)
- Chihiro Hosoda
- Department of Pharmacology, National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya-ku, Tokyo 157-8535, Japan
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Faber JE, Szymeczek CL, Cotecchia S, Thomas SA, Tanoue A, Tsujimoto G, Zhang H. α1-Adrenoceptor-dependent vascular hypertrophy and remodeling in murine hypoxic pulmonary hypertension. Am J Physiol Heart Circ Physiol 2007; 292:H2316-23. [PMID: 17220188 DOI: 10.1152/ajpheart.00792.2006] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Excessive proliferation of vascular wall cells underlies the development of elevated vascular resistance in hypoxic pulmonary hypertension (PH), but the responsible mechanisms remain unclear. Growth-promoting effects of catecholamines may contribute. Hypoxemia causes sympathoexcitation, and prolonged stimulation of α1-adrenoceptors (α1-ARs) induces hypertrophy and hyperplasia of arterial smooth muscle cells and adventitial fibroblasts. Catecholamine trophic actions in arteries are enhanced when other conditions favoring growth or remodeling are present, e.g., injury or altered shear stress, in isolated pulmonary arteries from rats with hypoxic PH. The present study examined the hypothesis that catecholamines contribute to pulmonary vascular remodeling in vivo in hypoxic PH. Mice genetically deficient in norepinephrine and epinephrine production [dopamine β-hydroxylase−/− (DBH−/−)] or α1-ARs were examined for alterations in PH, cardiac hypertrophy, and vascular remodeling after 21 days exposure to normobaric 0.1 inspired oxygen fraction (FiO2). A decrease in the lumen area and an increase in the wall thickness of arteries were strongly inhibited in knockout mice (order of extent of inhibition: DBH−/− = α1D-AR−/− > α1B-AR−/−). Distal muscularization of small arterioles was also reduced (DBH−/− > α1D-AR−/− > α1B-AR−/− mice). Despite these reductions, increases in right ventricular pressure and hypertrophy were not attenuated in DBH−/− and α1B-AR−/− mice. However, hematocrit increased more in these mice, possibly as a consequence of impaired cardiovascular activation that occurs during reduction of FiO2. In contrast, in α1D-AR−/− mice, where hematocrit increased the same as in wild-type mice, right ventricular pressure was reduced. These data suggest that catecholamine stimulation of α1B- and α1D-ARs contributes significantly to vascular remodeling in hypoxic PH.
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Affiliation(s)
- James E Faber
- Department of Cell and Molecular Physiology, University of North Carolina, Chapel Hill, NC 27599-7545, USA.
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Chin KM, Channick RN, Rubin LJ. Is Methamphetamine Use Associated With Idiopathic Pulmonary Arterial Hypertension? Chest 2006; 130:1657-63. [PMID: 17166979 DOI: 10.1378/chest.130.6.1657] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Amphetamine, methamphetamine, and cocaine are suspected of being pulmonary hypertension risk factors based on a small number of case reports along with pharmacologic similarities to fenfluramine, a diet drug associated with pulmonary arterial hypertension (PAH). We sought to determine whether rates of stimulant use are increased in patients believed to have idiopathic PAH compared with patients with PAH and known risk factors and patients with chronic thromboembolic pulmonary hypertension (CTEPH). METHODS In this retrospective study, rates of stimulant use were determined for 340 patients with idiopathic PAH, PAH and known risk factors, or CTEPH seen between November 2002 and April 2004. "Stimulant" use was defined as any reported use of amphetamine, methamphetamine, or cocaine. Odds of stimulant use were calculated using a polychotomous logistic regression model. RESULTS A history of stimulant use was found in 28.9% of patients with a diagnosis of idiopathic PAH, compared with 3.8% of patients with PAH and a known risk factor, and 4.3% of patients with CTEPH. After adjustment for differences in age, patients with idiopathic PAH were 10.14 times (95% confidence interval, 3.39 to 30.3; p < 0.0001) more likely to have used stimulants than patients with PAH and known risk factors, and 7.63 times (95% confidence interval, 2.99 to 19.5; p < 0.0001) more likely to have used stimulants than patients with CTEPH. CONCLUSIONS Patients with idiopathic PAH are significantly more likely to have used stimulants than patients with other forms of pulmonary hypertension.
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Affiliation(s)
- Kelly M Chin
- Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, St. Paul University Hospital, Dallas, TX, USA
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Faber JE, Szymeczek CL, Salvi SS, Zhang H. Enhanced α1-adrenergic trophic activity in pulmonary artery of hypoxic pulmonary hypertensive rats. Am J Physiol Heart Circ Physiol 2006; 291:H2272-81. [PMID: 16798826 DOI: 10.1152/ajpheart.00404.2006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mechanisms that induce the excessive proliferation of vascular wall cells in hypoxic pulmonary hypertension (PH) are not fully understood. Alveolar hypoxia causes sympathoexcitation, and norepinephrine can stimulate α1-adrenoceptor (α1-AR)-dependent hypertrophy/hyperplasia of smooth muscle cells and adventitial fibroblasts. Adrenergic trophic activity is augmented in systemic arteries by injury and altered shear stress, which are key pathogenic stimuli in hypoxic PH, and contributes to neointimal formation and flow-mediated hypertrophic remodeling. Here we examined whether norepinephrine stimulates growth of the pulmonary artery (PA) and whether this is augmented in PH. PA from normoxic and hypoxic rats [9 days of 0.1 fraction of inspired O2 (FiO2)] was studied in organ culture, where wall tension, Po2, and Pco2 were maintained at values present in normal and hypoxic PH rats. Norepinephrine treatment for 72 h increased DNA and protein content modestly in normoxic PA (+10%, P < 0.05). In hypoxic PA, these effects were augmented threefold ( P < 0.05), and protein synthesis was increased 34-fold ( P < 0.05). Inferior thoracic vena cava from normoxic or hypoxic rats was unaffected. Norepinephrine-induced growth in hypoxic PA was dose dependent, had efficacy greater than or equal to endothelin-1, required the presence of wall tension, and was inhibited by α1A-AR antagonist. In hypoxic pulmonary vasculature, α1A-AR was downregulated the least among α1-AR subtypes. These data demonstrate that norepinephrine has trophic activity in the PA that is augmented by PH. If evident in vivo in the pulmonary vasculature, adrenergic-induced growth may contribute to the vascular hyperplasia that participates in hypoxic PH.
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MESH Headings
- Adrenergic alpha-1 Receptor Agonists
- Adrenergic alpha-1 Receptor Antagonists
- Animals
- DNA/analysis
- DNA/metabolism
- Dose-Response Relationship, Drug
- Endothelin-1/pharmacology
- Fibroblasts/drug effects
- Fibroblasts/metabolism
- Hypertension, Pulmonary/etiology
- Hypertension, Pulmonary/pathology
- Hypertension, Pulmonary/physiopathology
- Hypoxia/complications
- Male
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Norepinephrine/pharmacology
- Organ Culture Techniques
- Proteins/analysis
- Proteins/metabolism
- Pulmonary Artery/drug effects
- Pulmonary Artery/pathology
- Rats
- Rats, Sprague-Dawley
- Receptors, Adrenergic, alpha-1/physiology
- Time Factors
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Affiliation(s)
- James E Faber
- Dept. of Cell and Molecular Physiology, 6309 MBRB, Univ. of North Carolina, Chapel Hill, NC 27599-7545, USA.
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Cavadas C, Céfai D, Rosmaninho-Salgado J, Vieira-Coelho MA, Moura E, Busso N, Pedrazzini T, Grand D, Rotman S, Waeber B, Aubert JF, Grouzmann E. Deletion of the neuropeptide Y (NPY) Y1 receptor gene reveals a regulatory role of NPY on catecholamine synthesis and secretion. Proc Natl Acad Sci U S A 2006; 103:10497-10502. [PMID: 16798884 PMCID: PMC1502486 DOI: 10.1073/pnas.0600913103] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The contribution of neuropeptide Y (NPY), deriving from adrenal medulla, to the adrenosympathetic tone is unknown. We found that in response to NPY, primary cultures of mouse adrenal chromaffin cells secreted catecholamine, and that this effect was abolished in cultures from NPY Y(1) receptor knockout mice (Y(1)-/-). Compared with wild-type mice (Y(1)+/+), the adrenal content and constitutive release of catecholamine were increased in chromaffin cells from Y(1)-/- mice. In resting animals, catecholamine plasma concentrations were higher in Y(1)-/- mice. Comparing the adrenal glands of both genotypes, no differences were observed in the area of the medulla, cortex, and X zone. The high turnover of adrenal catecholamine in Y(1)-/- mice was explained by the enhancement of tyrosine hydroxylase (TH) activity, although no change in the affinity of the enzyme was observed. The molecular interaction between the Y(1) receptor and TH was demonstrated by the fact that NPY markedly inhibited the forskolin-induced luciferin activity in Y(1) receptor-expressing SK-N-MC cells transfected with a TH promoter sequence. We propose that NPY controls the release and synthesis of catecholamine from the adrenal medulla and consequently contributes to the sympathoadrenal tone.
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Affiliation(s)
- Cláudia Cavadas
- *Center for Neurosciences and Cell Biology and Faculty of Pharmacy, University of Coimbra, 3004-517 Coimbra, Portugal
| | | | - Joana Rosmaninho-Salgado
- *Center for Neurosciences and Cell Biology and Faculty of Pharmacy, University of Coimbra, 3004-517 Coimbra, Portugal
| | | | - Eduardo Moura
- Institute of Pharmacology and Therapeutics, Faculty of Medicine, 4200-319 Porto, Portugal
| | | | | | | | - Samuel Rotman
- Institute of Pathology, Centre Hospitalier Universaire Vaudois, 1011 Lausanne, Switzerland; and
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Faber JE, Yang N. Balloon injury alters alpha-adrenoceptor expression across rat carotid artery wall. Clin Exp Pharmacol Physiol 2006; 33:204-10. [PMID: 16487263 DOI: 10.1111/j.1440-1681.2006.04347.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
alpha(1)-Adrenoceptors (AR) mediate growth factor-like activity of catecholamines on vascular smooth muscle cells (SMC) and adventitial fibroblasts. This trophic activity is strongly augmented by balloon injury, contributes significantly to subsequent proliferation, wall hypertrophy and lumen loss and is mediated by alpha(1A)- and alpha(1B)-AR. However, it is not known how injury augments adrenergic trophic activity. The aim of the present study was to examine alpha-AR expression in rat carotid artery and to test the hypothesis that balloon injury augments a(1)-AR expression. 2. Neointima, media and adventitia were isolated at various days after balloon injury of rat carotid artery and subjected to quantitative reverse transcription-polymerase chain reaction and radioligand binding. Cultured SMC were also studied. 3. Transcripts for alpha(1A)-, alpha(1B)-, alpha(1D)- and alpha(2D)-AR were expressed in different proportions in media and adventitia from uninjured carotid artery. Injury caused a reduction by as much as 85% at day 4 in all alpha-AR mRNA (but not cyclophilin) in both the media and adventitia. In both layers, expression returned to control by day 21 for alpha(2D)-AR and by day 42 for alpha(1A)-AR, but remained reduced by 25-50% for alpha(1B)- and alpha(1D)-AR at 42 days. alpha(1)-Adrenoceptor transcripts in the neointima at 21 and 42 days after injury were expressed at levels more than 80% lower than in the media or adventitia of uninjured carotid; alpha(2D)-AR mRNA was undetectable. The density of total alpha(1)-AR binding sites was similar in the media and adventitia of uninjured carotid. Density was reduced by approximately 60% in the intima-media and adventitia 21 days after injury. To examine possible mechanisms, early passaged cultured SMC were studied that express alpha(1D)- and alpha(1B)-AR at levels similar to in vivo but that do not express other alpha-AR. Basic fibroblast growth factor caused downregulation of alpha(1D)-AR mRNA and alpha(1)-AR density, without affecting mRNA half-life, whereas transforming growth factor-beta1 had no effect. Neither growth factor altered alpha(1B)-AR message expression. 4. These data demonstrate that: (i) carotid artery expresses the same four alpha-AR genes and similar total alpha(1)-AR density in the SMC media and fibroblast-rich adventitia; and (ii) injury induced enhancement of adrenergic trophic activity is not caused by upregulation of alpha(1)-AR, but, instead, is associated with a generalized reduction in alpha-AR expression.
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Affiliation(s)
- James E Faber
- Department of Cell and Molecular Physiology, University of North Carolina, Chapel Hill, North Carolina, USA.
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Johnson R, Webb JG, Newman WH, Wang Z. Regulation of Human Vascular Smooth Muscle Cell Migration by β-Adrenergic Receptors. Am Surg 2006. [DOI: 10.1177/000313480607200112] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Migration and proliferation of vascular smooth muscle cells (VSMCs) are two events involved in atherosclerosis, restenosis after balloon angioplasty, and stenosis of grafted vessels. Platelet-derived growth factor (PDGF) found in stenotic vessels is known to induce migration of VSMCs. VSMCs express both α- and β-adrenergic receptors on their surface, and blood vessels are innervated by the adrenergic nervous system and exposed to circulating epinephrine. We examined the role of these receptors on PDGF-induced migration of VSMCs. VSMCs were cultured from saphenous vein segments. Migration was stimulated by PDGF. Effect of pretreatment of VSMCs with the β-agonist isoproterenol, the α-agonist phenylephrine, or forskolin on PDGF-induced migration was examined with a modified Boyden chamber. Cell migration was quantitated by spectrophotometry. Intracellular cyclic AMP was determined by radioimmunoassay. PDGF significantly induced VSMC migration. Isoproterenol (0.1 and 1.0 μM) inhibited PDGF-induced migration by 30 per cent and 50 per cent, respectively. Forskolin (10 μM) completely blocked PDGF-induced migration. The migration inhibition by isoproterenol or forskolin was associated with a significant elevation of intracellular cyclic AMP. In contrast, phenylephrine had no effect on PDGF-induced migration or on cyclic AMP. Activation of β-adrenergic receptors and the consequent rise in intracellular cyclic AMP inhibits migration of VSMCs induced by PDGF. These results are consistent with the notion that adrenergic agonists with substantial β-receptor affinity, such as isoproterenol, can inhibit smooth muscle cell migration.
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Affiliation(s)
- Richard Johnson
- Department of Surgery, Mercer University School of Medicine, Macon, Georgia
| | - Jerry G. Webb
- Department of Pharmacology, Medical University of South Carolina, Charleston, South Carolina; and
| | - Walter H. Newman
- Department of Surgery, Mercer University School of Medicine, Macon, Georgia
- Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, Georgia
| | - Zhongbiao Wang
- Department of Surgery, Mercer University School of Medicine, Macon, Georgia
- Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, Georgia
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Erami C, Zhang H, Tanoue A, Tsujimoto G, Thomas SA, Faber JE. Adrenergic catecholamine trophic activity contributes to flow-mediated arterial remodeling. Am J Physiol Heart Circ Physiol 2005; 289:H744-53. [PMID: 15849236 DOI: 10.1152/ajpheart.00129.2005] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Stimulation of α1-adrenoceptors (ARs) induces proliferation, hypertrophy, and migration of vascular smooth muscle cells and adventitial fibroblasts in cell and organ culture. In vivo studies have confirmed this direct trophic action and found that endogenous catecholamines contribute to neointimal formation and wall hypertrophy induced by mechanical injury. In murine carotid artery, these effects are mediated by α1B-ARs, whereas α1D-ARs mediate contraction and α1A-ARs are not expressed. Herein, we examined whether catecholamines also contribute to arterial wall growth in a noninjury model, i.e., flow-mediated remodeling. In wild-type mice or mice deficient in norepinephrine and epinephrine synthesis [dopamine β-hydroxylase knockout (DBH-KO)], all distal branches of the left carotid artery (LC) except the thyroid artery were ligated to reduce flow in the LC and increase flow in the right carotid artery (RC). Twenty-one days later, negative hypertrophic remodeling of the LC [i.e., −20% (decrease) in lumen area, −2% in circumference of the external elastic lamina (CEEL), +98% (increase) in thickness of the intima media, and +71% in thickness for adventitia; P < 0.01 vs. sham ligation] and positive eutrophic remodeling of the RC [+23% in lumen area, +11% in CEEL; P < 0.01 vs. sham ligation] were inhibited in DBH-KO mice [LC: +10% intima media and +3% adventitia; RC: +9% lumen area and +3% CEEL]. This inhibition was associated with reduced proliferation in the RC and reduced apoptosis and leukocyte accumulation in the RC and LC when examined 5 days after ligation. Carotid remodeling in α1D-AR-knockout mice evidenced little or no inhibition, which suggests dependence on α1B-ARs. These findings suggest that catecholamine-induced trophic activity contributes to both flow-mediated negative remodeling and adaptive positive arterial remodeling.
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Affiliation(s)
- Cauveh Erami
- Department of Cell and Molecular Physiology, 474 MSRB, Univ. of North Carolina, Chapel Hill, NC 27599-7545, USA
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Chalothorn D, Zhang H, Clayton JA, Thomas SA, Faber JE. Catecholamines augment collateral vessel growth and angiogenesis in hindlimb ischemia. Am J Physiol Heart Circ Physiol 2005; 289:H947-59. [PMID: 15833801 DOI: 10.1152/ajpheart.00952.2004] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Catecholamine stimulation of α1-adrenoceptors exerts growth factor-like activity, mediated by generation of reactive oxygen species, on arterial smooth muscle cells and adventitial fibroblasts and contributes to hypertrophy and hyperplasia in models of vascular injury and disease. Adrenergic trophic activity also contributes to flow-mediated positive arterial remodeling by augmenting proliferation and leukocyte accumulation. To further examine this concept, we studied whether catecholamines contribute to collateral growth and angiogenesis in hindlimb insufficiency. Support for this hypothesis includes the above-mentioned studies, evidence that ischemia augments norepinephrine release from sympathetic nerves, and proposed involvement of reactive oxygen species in angiogenesis and collateral growth. Mice deficient in catecholamine synthesis [by gene deletion of dopamine β-hydroxylase (DBH−/−)] were studied. At 3 wk after femoral artery ligation, increases in adductor muscle perfusion were similar in DBH−/− and wild-type mice, whereas recovery of plantar perfusion and calf microsphere flow were attenuated, although not significantly. Preexisting collaterals in adductor of wild-type mice showed increases in lumen diameter (60%) and medial and adventitial thickness (57 and 119%, P < 0.05 here and below). Lumen diameter increased similarly in DBH−/− mice (52%); however, increases in medial and adventitial thicknesses were reduced (30 and 65%). Leukocyte accumulation in the adventitia/periadventitia of collaterals was 39% less in DBH−/− mice. Increased density of α-smooth muscle actin-positive vessels in wild-type adductor (45%) was inhibited in DBH−/− mice (2%). Although both groups experienced similar atrophy in the gastrocnemius (∼22%), the increase in capillary-to-muscle fiber ratio in wild-type mice (21%) was inhibited in DBH−/− mice (7%). These data suggest that catecholamines may contribute to collateral growth and angiogenesis in tissue ischemia.
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Affiliation(s)
- Dan Chalothorn
- Department of Cell and Molecular Physiology, 103 Mason Farm Rd., 6309 MBRB, CB 7545, Univ. of North Carolina, Chapel Hill, NC 27599-7545, USA
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McGrath JC, Deighan C, Briones AM, Shafaroudi MM, McBride M, Adler J, Arribas SM, Vila E, Daly CJ. New aspects of vascular remodelling: the involvement of all vascular cell types. Exp Physiol 2005; 90:469-75. [PMID: 15894533 DOI: 10.1113/expphysiol.2005.030130] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Conventionally, the architecture of arteries is based around the close-packed smooth muscle cells and extracellular matrix. However, the adventitia and endothelium are now viewed as key players in vascular growth and repair. A new dynamic picture has emerged of blood vessels in a constant state of self-maintenance. Recent work raises fundamental questions about the cellular heterogeneity of arteries and the time course and triggering of normal and pathological remodelling. A common denominator emerging in hypertensive remodelling is an early increase in adventitial cell density suggesting that adventitial cells drive remodelling and may initiate subsequent changes such as re-arrangement of smooth muscle cells and extracellular matrix. The organization of vascular smooth muscle cells follows regular arrangements that can be modelled mathematically. In hypertension, new patterns can be quantified in these terms and give insights to how structure affects function. As with smooth muscle, little is known about the organization of the vascular endothelium, or its role in vascular remodelling. Current observations suggest that there may be a close relationship between the helical organization of smooth muscle cells and the underlying pattern of endothelial cells. The function of myoendothelial connections is a topic of great current interest and may relate to the structure of the internal elastic lamina through which the connections must pass. In hypertensive remodelling this must present an organizational challenge. The objective of this paper is to show how the functions of blood vessels depend on their architecture and a continuous interaction of different cell types and extracellular proteins.
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MESH Headings
- Animals
- Arteriosclerosis/pathology
- Blood Vessels/cytology
- Blood Vessels/pathology
- Blood Vessels/physiology
- Endothelial Cells/physiology
- Endothelium, Vascular/physiology
- Extracellular Matrix/physiology
- Humans
- Hypertension/pathology
- Intracellular Membranes/physiology
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/pathology
- Muscle, Smooth, Vascular/physiology
- Myocytes, Smooth Muscle/physiology
- Oxidative Stress/physiology
- Receptors, Adrenergic, alpha-1/physiology
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Affiliation(s)
- John C McGrath
- Autonomic Physiology Unit, Institute of Biomedical & Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
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Lei B, Morris DP, Smith MP, Svetkey LP, Newman MF, Rotter JI, Buchanan TA, Beckstrom-Sternberg SM, Green ED, Schwinn DA. Novel human alpha1a-adrenoceptor single nucleotide polymorphisms alter receptor pharmacology and biological function. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2005; 371:229-39. [PMID: 15900517 PMCID: PMC2367253 DOI: 10.1007/s00210-005-1019-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2004] [Accepted: 12/21/2004] [Indexed: 11/26/2022]
Abstract
We identified nine naturally-occurring human single nucleotide polymorphisms (SNPs) in the alpha(1a)-adrenoceptor (alpha(1a)AR) coding region, seven of which result in amino acid change. Utilizing rat-1 fibroblasts stably expressing wild type alpha(1a)AR or each SNP at both high and low levels, we investigated the effect of these SNPs on receptor function. Compared with wild type, two SNPs (R166K, V311I) cause a decrease in binding affinity for agonists norepinephrine, epinephrine, and phenylephrine, and also shift the dose-response curve for norepinephrine stimulation of inositol phosphate (IP) production to the right (reduced potency) without altering maximal IP activity. In addition, SNP V311I and I200S display altered antagonist binding. Interestingly, a receptor with SNP G247R (located in the third intracellular loop) displays increased maximal receptor IP activity and stimulates cell growth. The increased receptor signaling for alpha(1a)AR G247R is not mediated by altered ligand binding or a deficiency in agonist-mediated desensitization, but appears to be related to enhanced receptor-G protein coupling. In conclusion, four naturally-occurring human alpha(1a)AR SNPs induce altered receptor pharmacology and/or biological activity. This finding has potentially important implications in many areas of medicine and can be used to guide alpha(1a)AR SNP choice for future clinical studies.
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MESH Headings
- Adrenergic alpha-Agonists/pharmacology
- Adrenergic alpha-Antagonists/pharmacology
- Amino Acid Sequence
- Amino Acid Substitution
- Animals
- Cell Division/genetics
- Cells, Cultured
- Dose-Response Relationship, Drug
- GTP-Binding Proteins/metabolism
- Humans
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Phosphoric Monoester Hydrolases/metabolism
- Polymorphism, Single Nucleotide
- Radioligand Assay
- Rats
- Receptors, Adrenergic, alpha-1/drug effects
- Receptors, Adrenergic, alpha-1/genetics
- Receptors, Adrenergic, alpha-1/metabolism
- Signal Transduction
- Transfection
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Affiliation(s)
- Beilei Lei
- Department of Anesthesiology, Duke University Medical Center, Box 3094 Durham, NC, 27710, USA
- Department of Pharmacology/Cancer Biology Duke University Medical Center, Durham, NC, USA
| | - Daniel P. Morris
- Department of Anesthesiology, Duke University Medical Center, Box 3094 Durham, NC, 27710, USA
- Department of Pharmacology/Cancer Biology Duke University Medical Center, Durham, NC, USA
| | - Michael P. Smith
- Department of Anesthesiology, Duke University Medical Center, Box 3094 Durham, NC, 27710, USA
- Department of Pharmacology/Cancer Biology Duke University Medical Center, Durham, NC, USA
| | - Laura P. Svetkey
- Department of Medicine, Duke University Medical Center, Durham, NC, USA
| | - Mark F. Newman
- Department of Anesthesiology, Duke University Medical Center, Box 3094 Durham, NC, 27710, USA
| | - Jerome I. Rotter
- Department of Medicine, Cedars-Sinai Medical Center and the University of California, Los Angeles, CA, USA
- Department of Pediatrics, Cedars-Sinai Medical Center and the University of California, Los Angeles, CA, USA
- Department of Human Genetics, Cedars-Sinai Medical Center and the University of California, Los Angeles, CA, USA
| | - Thomas A. Buchanan
- Department of Medicine, University of Southern California, Los Angeles, CA, USA
| | | | - Eric D. Green
- Genome Technology Branch and NIH Intramural Sequencing Center, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Debra A. Schwinn
- Department of Anesthesiology, Duke University Medical Center, Box 3094 Durham, NC, 27710, USA, e-mail: , Tel.: +1-919-6814781, Fax: +1-919-6814776
- Department of Pharmacology/Cancer Biology Duke University Medical Center, Durham, NC, USA
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Matsumaru T, Sugiura R, Sakai K, Igarashi T, Kuno T. Comparison of toxicity and toxicokinetics/pharmacokinetics of an alpha 1L-adrenoceptor agonist in rats and rhesus monkeys. J Pharmacol Sci 2005; 97:273-83. [PMID: 15699575 DOI: 10.1254/jphs.fp0040248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
We have investigated the toxicity of an alpha(1L)-adrenoceptor agonist, ESR 1150 CL, and compared the toxicokinetics and pharmacokinetics in rats and monkeys. In rats, this compound induced death with remarkable sacculated aneurysms of the aorta in groups given more than 3 mg/kg per day in a 4-week repeated oral administration study. On the other hand, these findings were not observed in monkeys during a 2-week repeated oral administration study at doses up to 30 mg/kg per day. Orally administered ESR 1150 CL raised blood pressure transiently and dose-dependently during the 4-week repeated study in rats, whereas no increase of blood pressure was observed during the 2-week oral toxicity study in monkeys. Contrary to our expectation, the exposure level of ESR 1150 CL in rats was not higher than that in monkeys in the toxicokinetic evaluation. Pharmacokinetic evaluation indicated good absorption of the compound, but the bioavailability was very low in both rats and monkeys. These findings suggest that the potent species difference in toxicity of ESR 1150 CL between rats and monkeys does not depend on differences of toxicokinetics/pharmacokinetics. Rather, we suggest that the reason is likely to be species difference in the biological susceptibility of the alpha(1L)-adrenoceptor subtypes between rats and monkeys, which would be closely related with the effect on blood pressure by alpha(1L)-adrenoceptor agonist.
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Affiliation(s)
- Takehisa Matsumaru
- Division of Molecular Pharmacology and Pharmacogenomics, Department of Genome Sciences, Kobe University Graduate School of Medicine, Hyogo, Japan
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Abstract
The incidence of cardiac failure and chronic renal failure is increasing and it has now become clear that the co-existence of the two problems has an extremely bad prognosis. We propose the severe cardiorenal syndrome (SCRS), a pathophysiological condition in which combined cardiac and renal dysfunction amplifies progression of failure of the individual organ, so that cardiovascular morbidity and mortality in this patient group is at least an order of magnitude higher than in the general population. Guyton has provided an excellent framework describing the physiological relationships between cardiac output, extracellular fluid volume control, and blood pressure. While this model is also sufficient to understand systemic haemodynamics in combined cardiac and renal failure, not all aspects of the observed accelerated atherosclerosis, structural myocardial changes, and further decline of renal function can be explained. Since increased activity of the renin-angiotensin system, oxidative stress, inflammation, and increased activity of the sympathetic nervous system seem to be cornerstones of the pathophysiology in combined chronic renal disease and heart failure, we have explored the potential interactions between these cardiorenal connectors. As such, the cardiorenal connection is an interactive network with positive feedback loops, which, in our view, forms the basis for the SCRS.
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Affiliation(s)
- Lennart G Bongartz
- Department of Cardiology, Heart-Lung Centre Utrecht, Utrecht, The Netherlands
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Zhang H, Cotecchia S, Thomas SA, Tanoue A, Tsujimoto G, Faber JE. Gene deletion of dopamine β-hydroxylase and α1-adrenoceptors demonstrates involvement of catecholamines in vascular remodeling. Am J Physiol Heart Circ Physiol 2004; 287:H2106-14. [PMID: 15231500 DOI: 10.1152/ajpheart.00290.2004] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In vitro studies have shown that stimulation of α1-adrenoceptors (ARs) directly induces proliferation, hypertrophy, and migration of arterial smooth muscle cells and adventitial fibroblasts. In vivo studies confirmed these findings and showed that catecholamine trophic activity becomes excessive after experimental balloon injury and contributes to neointimal growth, adventitial thickening, and lumen loss. However, past studies have been limited by selectivity of pharmacological agents. The aim of this study, in which mice devoid of norepinephrine and epinephrine synthesis [dopamine β-hydroxylase (DBH−/−)] or deficient in α1-AR subtypes expressed in murine carotid (α1B-AR−/− and α1D-AR−/−) were used, was to test the hypothesis that catecholamines contribute to wall hypertrophy after injury. At 3 wk after injury of wild-type mice, lumen area and carotid circumference increased significantly, and hypertrophy of media and adventitia was in excess of that needed to restore circumferential wall stress to normal. In DBH−/− and α1B-AR−/− mice, increases in lumen area, circumference, and hypertrophy of the media and adventitia were reduced by 50–91%, resulting in restoration of wall tension to nearly normal (DBH−/−) or normal (α1B-AR−/−). In contrast, in α1D-AR−/− mice, increases in lumen area, circumference, and wall hypertrophy were unaffected and wall thickening remained in excess of that required to return tension to normal. When examined 5 days after injury, proliferation and leukocyte infiltration were inhibited in DBH−/− mice. These studies suggest that the trophic effects of catecholamines are mediated primarily by α1B-ARs in mouse carotid and contribute to hypertrophic growth after vascular injury.
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Affiliation(s)
- Hua Zhang
- Dept. of Cell and Molecular Physiology, 6309 MBRB, Univ. of North Carolina, Chapel Hill, NC 27599-7545, USA
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