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Sandroni PB, Schroder MA, Hawkins HT, Bailon JD, Huang W, Hagen JT, Montgomery M, Hong SJ, Chin AL, Zhang J, Rodrigo MC, Kim B, Simpson PC, Schisler JC, Ellis JM, Fisher-Wellman KH, Jensen BC. The alpha-1A adrenergic receptor regulates mitochondrial oxidative metabolism in the mouse heart. J Mol Cell Cardiol 2024; 187:101-117. [PMID: 38331556 PMCID: PMC10861168 DOI: 10.1016/j.yjmcc.2023.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 12/11/2023] [Accepted: 12/12/2023] [Indexed: 02/10/2024]
Abstract
AIMS The sympathetic nervous system regulates numerous critical aspects of mitochondrial function in the heart through activation of adrenergic receptors (ARs) on cardiomyocytes. Mounting evidence suggests that α1-ARs, particularly the α1A subtype, are cardioprotective and may mitigate the deleterious effects of chronic β-AR activation by shared ligands. The mechanisms underlying these adaptive effects remain unclear. Here, we tested the hypothesis that α1A-ARs adaptively regulate cardiomyocyte oxidative metabolism in both the uninjured and infarcted heart. METHODS We used high resolution respirometry, fatty acid oxidation (FAO) enzyme assays, substrate-specific electron transport chain (ETC) enzyme assays, transmission electron microscopy (TEM) and proteomics to characterize mitochondrial function comprehensively in the uninjured hearts of wild type and α1A-AR knockout mice and defined the effects of chronic β-AR activation and myocardial infarction on selected mitochondrial functions. RESULTS We found that isolated cardiac mitochondria from α1A-KO mice had deficits in fatty acid-dependent respiration, FAO, and ETC enzyme activity. TEM revealed abnormalities of mitochondrial morphology characteristic of these functional deficits. The selective α1A-AR agonist A61603 enhanced fatty-acid dependent respiration, fatty acid oxidation, and ETC enzyme activity in isolated cardiac mitochondria. The β-AR agonist isoproterenol enhanced oxidative stress in vitro and this adverse effect was mitigated by A61603. A61603 enhanced ETC Complex I activity and protected contractile function following myocardial infarction. CONCLUSIONS Collectively, these novel findings position α1A-ARs as critical regulators of cardiomyocyte metabolism in the basal state and suggest that metabolic mechanisms may underlie the protective effects of α1A-AR activation in the failing heart.
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Affiliation(s)
- Peyton B Sandroni
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America; McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America
| | - Melissa A Schroder
- McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America
| | - Hunter T Hawkins
- McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America
| | - Julian D Bailon
- McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America
| | - Wei Huang
- McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America
| | - James T Hagen
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, United States of America; East Carolina University Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, United States of America
| | - McLane Montgomery
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, United States of America; East Carolina University Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, United States of America
| | - Seok J Hong
- McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America
| | - Andrew L Chin
- McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America
| | - Jiandong Zhang
- McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America; Department of Medicine, Division of Cardiology, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America
| | - Manoj C Rodrigo
- Cytokinetics, Inc., South San Francisco, CA, United States of America
| | - Boa Kim
- McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America; Department of Cell Biology and Physiology, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America
| | - Paul C Simpson
- Department of Medicine and Research Service, San Francisco Veterans Affairs Medical Center, San Francisco, CA, United States of America; Cardiovascular Research Institute, University of California, San Francisco, CA, United States of America
| | - Jonathan C Schisler
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America; McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America
| | - Jessica M Ellis
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, United States of America; East Carolina University Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, United States of America
| | - Kelsey H Fisher-Wellman
- Department of Physiology, East Carolina University, Brody School of Medicine, Greenville, NC, United States of America; East Carolina University Diabetes and Obesity Institute, East Carolina University, Brody School of Medicine, Greenville, NC, United States of America
| | - Brian C Jensen
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America; McAllister Heart Institute, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America; Department of Medicine, Division of Cardiology, University of North Carolina School of Medicine, Chapel Hill, NC, United States of America.
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Menon A, Hong L, Savio-Galimberti E, Sridhar A, Youn SW, Zhang M, Kor K, Blair M, Kupershmidt S, Darbar D. Electrophysiologic and molecular mechanisms of a frameshift NPPA mutation linked with familial atrial fibrillation. J Mol Cell Cardiol 2019; 132:24-35. [PMID: 31077706 DOI: 10.1016/j.yjmcc.2019.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/01/2019] [Accepted: 05/03/2019] [Indexed: 11/28/2022]
Abstract
A frameshift (fs) mutation in the natriuretic peptide precursor A (NPPA) gene, encoding a mutant atrial natriuretic peptide (Mut-ANP), has been linked with familial atrial fibrillation (AF) but the underlying mechanisms by which the mutation causes AF remain unclear. We engineered 2 transgenic (TG) mouse lines expressing the wild-type (WT)-NPPA gene (H-WT-NPPA) and the human fs-Mut-NPPA gene (H-fsMut-NPPA) to test the hypothesis that mice overexpressing the human NPPA mutation are more susceptible to AF and elucidate the underlying electrophysiologic and molecular mechanisms. Transthoracic echocardiography and surface electrocardiography (ECG) were performed in H-fsMut-NPPA, H-WT-NPPA, and Non-TG mice. Invasive electrophysiology, immunohistochemistry, Western blotting and patch clamping of membrane potentials were performed. To examine the role of the Mut-ANP in ion channel remodeling, we measured plasma cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) levels and protein kinase A (PKA) activity in the 3 groups of mice. In H-fsMut-NPPA mice mean arterial pressure (MAP) was reduced when compared to H-WT-NPPA and Non-TG mice. Furthermore, injection of synthetic fs-Mut-ANP lowered the MAP in H-WT-NPPA and Non-TG mice while synthetic WT-ANP had no effect on MAP in the 3 groups of mice. ECG characterization revealed significantly prolonged QRS duration in H-fsMut-NPPA mice when compared to the other two groups. Trans-Esophageal (TE) atrial pacing of H-fsMut-NPPA mice showed increased AF burden and AF episodes when compared with H-WT-NPPA or Non-TG mice. The cardiac Na+ (NaV1.5) and Ca2+ (CaV1.2/CaV1.3) channel expression and currents (INa, ICaL) and action potential durations (APD90/APD50/APD20) were significantly reduced in H-fsMut-NPPA mice while the rectifier K+ channel current (IKs) was markedly increased when compared to the other 2 groups of mice. In addition, plasma cGMP levels were only increased in H-fsMut-NPPA mice with a corresponding reduction in plasma cAMP levels and PKA activity. In summary, we showed that mice overexpressing an AF-linked NPPA mutation are more prone to develop AF and this risk is mediated in part by remodeling of the cardiac Na+, Ca2+ and K+ channels creating an electrophysiologic substrate for reentrant AF.
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Affiliation(s)
- Ambili Menon
- Departments of Medicine, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Liang Hong
- Departments of Medicine, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Eleonora Savio-Galimberti
- Department of Biomedical Sciences, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, United States of America
| | - Arvind Sridhar
- Departments of Medicine, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Seock-Won Youn
- Departments of Medicine, University of Illinois at Chicago, Chicago, IL, United States of America; Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Meihong Zhang
- Departments of Medicine, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Kaylen Kor
- Department of Pharmacology, Vanderbilt University Medical Center, United States of America
| | - Marcia Blair
- Department of Pharmacology, Vanderbilt University Medical Center, United States of America
| | - Sabina Kupershmidt
- Department of Nursing, University of South Dakota Sioux Falls, SD, United States of America
| | - Dawood Darbar
- Departments of Medicine, University of Illinois at Chicago, Chicago, IL, United States of America; Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, United States of America; Pharmacology, University of Illinois at Chicago, Chicago, IL, United States of America.
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Docherty JR. The pharmacology of α 1-adrenoceptor subtypes. Eur J Pharmacol 2019; 855:305-320. [PMID: 31067439 DOI: 10.1016/j.ejphar.2019.04.047] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 04/17/2019] [Accepted: 04/29/2019] [Indexed: 01/30/2023]
Abstract
This review examines the functions of α1-adrenoceptor subtypes, particularly in terms of contraction of smooth muscle. There are 3 subtypes of α1-adrenoceptor, α1A- α1B- and α1D-adrenoceptors. Evidence is presented that the postulated α1L-adrenoceptor is simply the native α1A-adrenoceptor at which prazosin has low potency. In most isolated tissue studies, smooth muscle contractions to exogenous agonists are mediated particularly by α1A-, with a lesser role for α1D-adrenoceptors, but α1B-adrenoceptors are clearly involved in contractions of some tissues, for example, the spleen. However, nerve-evoked responses are the most crucial physiologically, so that these studies of exogenous agonists may overestimate the importance of α1A-adrenoceptors. The major α1-adrenoceptors involved in blood pressure control by sympathetic nerves are the α1D- and the α1A-adrenoceptors, mediating peripheral vasoconstrictor actions. As noradrenaline has high potency at α1D-adrenceptors, these receptors mediate the fastest response and seem to be targets for neurally released noradrenaline especially to low frequency stimulation, with α1A-adrenoceptors being more important at high frequencies of stimulation. This is true in rodent vas deferens and may be true in vasopressor nerves controlling peripheral resistance and tissue blood flow. The αlA-adrenoceptor may act mainly through Ca2+ entry through L-type channels, whereas the α1D-adrenoceptor may act mainly through T-type channels and exhaustable Ca2+ stores. α1-Adrenoceptors may also act through non-G-protein linked second messenger systems. In many tissues, multiple subtypes of α-adrenoceptor are present, and this may be regarded as the norm rather than exception, although one receptor subtype is usually predominant.
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Affiliation(s)
- James R Docherty
- Department of Physiology, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland.
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Yeh CC, Fan Y, Xu Y, Yang YL, Simpson PC, Mann MJ. Shift toward greater pathologic post-myocardial infarction remodeling with loss of the adaptive hypertrophic signaling of alpha1 adrenergic receptors in mice. PLoS One 2017; 12:e0188471. [PMID: 29216197 PMCID: PMC5720786 DOI: 10.1371/journal.pone.0188471] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 11/07/2017] [Indexed: 11/18/2022] Open
Abstract
Rationale We have hypothesized that post-infarction cardiac remodeling can be influenced by shifts in the balance between intracellular mediators of “pathologic” and “physiologic” hypertrophy. Although alpha1 adrenergic receptors (alpha1-ARs) mediate pro-adaptive hypertrophy during pressure overload, little is known about their role or downstream mediators after myocardial infarction. Methods We performed loss-of-function experiments via coronary ligation in alpha1A-AR knockout (AKO) mice. Post-myocardial infarction (MI) remodeling was evaluated via echocardiography, quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis of cardiac fetal gene expression, histologic analysis of myocyte size, post-MI fibrosis and apoptosis, and Western blot analysis of apoptotic regulators. Results Alpha1A-AR knockout paradoxically increased post-MI hypertrophy compared to wild type controls (WT), but also increased ventricular dilatation, fibrosis, apoptosis, and 4-week post-MI mortality (64% in AKO vs. 25% in WT, P = 0.02), suggesting a shift toward greater pathologic hypertrophy in the absence of pro-adaptive alpha1A effects. alpha1A-AR knockout increased phospho-p38 levels in the pre-MI myocardium compared to WT (0.55 ± 0.16 vs. 0.03 ± 0.01, P<0.05) but decreased phospho-ERK1/2 post-MI (0.49 ± 0.35 arbitrary units vs. 1.55 ± 0.43 in WT, P<0.05). Furthermore, expression of pro-apoptotic factor Bax was increased (1.19 ± 0.15 vs. 0.78 ± 0.08, P<0.05) and expression of anti-apoptotic factors Bcl2 was decreased (0.26 ± 0.01 vs. 0.55 ± 0.06, P<0.01) compared to WT. Conclusions Alpha1A-AR provides an important counterbalance to pathologic pathways during post-MI remodeling that may be mediated through ERK1/2 signaling; these observations provide support for further development of an alpha1A-AR/ERK-based molecular intervention for this chronic, often fatal disease.
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Affiliation(s)
- Che-Chung Yeh
- Cardiothoracic Translational Research Laboratory, University of California San Francisco, San Francisco, California, United States of America
| | - Yanying Fan
- Cardiothoracic Translational Research Laboratory, University of California San Francisco, San Francisco, California, United States of America
| | - Yanchun Xu
- Cardiothoracic Translational Research Laboratory, University of California San Francisco, San Francisco, California, United States of America
| | - Yi-Lin Yang
- Cardiothoracic Translational Research Laboratory, University of California San Francisco, San Francisco, California, United States of America
| | - Paul C. Simpson
- Division of Cardiology, Veterans Affairs Medical Center and University of California San Francisco, San Francisco, California, United States of America
| | - Michael J. Mann
- Cardiothoracic Translational Research Laboratory, University of California San Francisco, San Francisco, California, United States of America
- * E-mail:
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Altoama K, Mallem MY, Thorin C, Betti E, Desfontis JC. Effect of nebivolol treatment during pregnancy on the intrauterine fetal growth, mortality and pup postnatal development in the l-NAME-induced hypertensive rats. Eur J Pharmacol 2016; 791:465-472. [DOI: 10.1016/j.ejphar.2016.09.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 09/14/2016] [Accepted: 09/19/2016] [Indexed: 01/14/2023]
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Altoama K, Yassine Mallem M, Thorin C, Betti E, Desfontis JC. Effect of nebivolol treatment during pregnancy on the genital circulation, fetal growth and postnatal development in the Wistar rat. Eur J Pharmacol 2015; 758:31-9. [DOI: 10.1016/j.ejphar.2015.04.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 03/27/2015] [Accepted: 04/01/2015] [Indexed: 12/14/2022]
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Zacharia J, Mauban JRH, Raina H, Fisher SA, Wier WG. High vascular tone of mouse femoral arteries in vivo is determined by sympathetic nerve activity via α1A- and α1D-adrenoceptor subtypes. PLoS One 2013; 8:e65969. [PMID: 23776582 PMCID: PMC3680395 DOI: 10.1371/journal.pone.0065969] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 05/02/2013] [Indexed: 02/04/2023] Open
Abstract
Background and purpose Determining the role of vascular receptors in vivo is difficult and not readily accomplished by systemic application of antagonists or genetic manipulations. Here we used intravital microscopy to measure the contributions of sympathetic receptors, particularly α1-adrenoceptor subtypes, to contractile activation of femoral artery in vivo. Experimental approach Diameter and intracellular calcium ([Ca2+]i) in femoral arteries were determined by intravital fluorescence microscopy in mice expressing a Myosin Light Chain Kinase (MLCK) based calcium-calmodulin biosensor. Pharmacological agents were applied locally to the femoral artery to determine the contributions of vascular receptors to tonic contraction and [Ca2+]i,. Key results In the anesthetized animal, femoral arteries were constricted to a diameter equal to 54% of their passive diameter (i.e. tone = 46%). Of this total basal tone, 16% was blocked by RS79948 (0.1 µM) and thus attributable to α2-adrenoceptors. A further 46% was blocked by prazosin (0.1 µM) and thus attributable to α1-adrenoceptors. Blockade of P2X and NPY1 receptors with suramin (0.5 mM) and BIBP3226 (1.0 µM) respectively, reduced tone by a further 22%, leaving 16% of basal tone unaffected at these concentrations of antagonists. Application of RS100329 (α1A-selective antagonist) and BMY7378 (α1D-selective) decreased tone by 29% and 26%, respectively, and reduced [Ca2+]i. Chloroethylclonidine (1 µM preferential for α1B-) had no effect. Abolition of sympathetic nerve activity (hexamethonium, i.p.) reduced basal tone by 90%. Conclusion and Implications Tone of mouse femoral arteries in vivo is almost entirely sympathetic in origin. Activation of α1A- and α1D-adrenoceptors elevates [Ca2+]i and accounts for at least 55% of the tone.
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Affiliation(s)
- Joseph Zacharia
- University of Maryland, School of Medicine, Baltimore, Maryland, United States of America.
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Kolb EM, Kelly SA, Garland T. Mice from lines selectively bred for high voluntary wheel running exhibit lower blood pressure during withdrawal from wheel access. Physiol Behav 2013; 112-113:49-55. [PMID: 23458632 DOI: 10.1016/j.physbeh.2013.02.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 11/23/2012] [Accepted: 02/20/2013] [Indexed: 01/23/2023]
Abstract
Exercise is known to be rewarding and have positive effects on mental and physical health. Excessive exercise, however, can be the result of an underlying behavioral/physiological addiction. Both humans who exercise regularly and rodent models of exercise addiction sometimes display behavioral withdrawal symptoms, including depression and anxiety, when exercise is denied. However, few studies have examined the physiological state that occurs during this withdrawal period. Alterations in blood pressure (BP) are common physiological indicators of withdrawal in a variety of addictions. In this study, we examined exercise withdrawal in four replicate lines of mice selectively bred for high voluntary wheel running (HR lines). Mice from the HR lines run almost 3-fold greater distances on wheels than those from non-selected control lines, and have altered brain activity as well as increased behavioral despair when wheel access is removed. We tested the hypothesis that male HR mice have an altered cardiovascular response (heart rate, systolic, diastolic, and mean arterial pressure [MAP]) during exercise withdrawal. Measurements using an occlusion tail-cuff system were taken during 8 days of baseline, 6 days of wheel access, and 2 days of withdrawal (wheel access blocked). During withdrawal, HR mice had significantly lower systolic BP, diastolic BP, and MAP than controls, potentially indicating a differential dependence on voluntary wheel running in HR mice. This is the first characterization of a cardiovascular withdrawal response in an animal model of high voluntary exercise.
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Affiliation(s)
- Erik M Kolb
- Department of Biology, University of California, Riverside, CA 92521, USA
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Dorn GW. Adrenergic signaling polymorphisms and their impact on cardiovascular disease. Physiol Rev 2010; 90:1013-62. [PMID: 20664078 DOI: 10.1152/physrev.00001.2010] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
This review examines the impact of recent discoveries defining personal genetics of adrenergic signaling polymorphisms on scientific discovery and medical practice related to cardiovascular diseases. The adrenergic system is the major regulator of minute-by-minute cardiovascular function. Inhibition of adrenergic signaling with pharmacological beta-adrenergic receptor antagonists (beta-blockers) is first-line therapy for heart failure and hypertension. Advances in pharmacology, molecular biology, and genetics of adrenergic signaling pathways have brought us to the point where personal genetic differences in adrenergic signaling factors are being assessed as determinants of risk or progression of cardiovascular disease. For a few polymorphisms, functional data generated in cell-based systems, genetic mouse models, and pharmacological provocation of human subjects are concordant with population studies that suggest altered risk of cardiovascular disease or therapeutic response to beta-blockers. For the majority of adrenergic pathway polymorphisms however, published data conflict, and the clinical relevance of individual genotyping remains uncertain. Here, the current state of laboratory and clinical evidence that adrenergic pathway polymorphisms can affect cardiovascular pathophysiology is comprehensively reviewed and compared, with a goal of placing these data in the broad context of potential clinical applicability.
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Affiliation(s)
- Gerald W Dorn
- Center for Pharmacogenomics, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
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Sanbe A, Tanaka Y, Fujiwara Y, Miyauchi N, Mizutani R, Yamauchi J, Cotecchia S, Koike K, Tsujimoto G, Tanoue A. Enhanced vascular contractility in alpha1-adrenergic receptor-deficient mice. Life Sci 2009; 84:713-8. [DOI: 10.1016/j.lfs.2009.02.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2008] [Revised: 01/28/2009] [Accepted: 02/12/2009] [Indexed: 11/24/2022]
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