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Behringer EJ. Impact of aging on vascular ion channels: perspectives and knowledge gaps across major organ systems. Am J Physiol Heart Circ Physiol 2023; 325:H1012-H1038. [PMID: 37624095 PMCID: PMC10908410 DOI: 10.1152/ajpheart.00288.2023] [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: 05/16/2023] [Revised: 08/21/2023] [Accepted: 08/21/2023] [Indexed: 08/26/2023]
Abstract
Individuals aged ≥65 yr will comprise ∼20% of the global population by 2030. Cardiovascular disease remains the leading cause of death in the world with age-related endothelial "dysfunction" as a key risk factor. As an organ in and of itself, vascular endothelium courses throughout the mammalian body to coordinate blood flow to all other organs and tissues (e.g., brain, heart, lung, skeletal muscle, gut, kidney, skin) in accord with metabolic demand. In turn, emerging evidence demonstrates that vascular aging and its comorbidities (e.g., neurodegeneration, diabetes, hypertension, kidney disease, heart failure, and cancer) are "channelopathies" in large part. With an emphasis on distinct functional traits and common arrangements across major organs systems, the present literature review encompasses regulation of vascular ion channels that underlie blood flow control throughout the body. The regulation of myoendothelial coupling and local versus conducted signaling are discussed with new perspectives for aging and the development of chronic diseases. Although equipped with an awareness of knowledge gaps in the vascular aging field, a section has been included to encompass general feasibility, role of biological sex, and additional conceptual and experimental considerations (e.g., cell regression and proliferation, gene profile analyses). The ultimate goal is for the reader to see and understand major points of deterioration in vascular function while gaining the ability to think of potential mechanistic and therapeutic strategies to sustain organ perfusion and whole body health with aging.
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Affiliation(s)
- Erik J Behringer
- Basic Sciences, Loma Linda University, Loma Linda, California, United States
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Grunz EA, Jones BW, Lateef OM, Sen S, Wilkinson K, Joshi T, Boerman EM. Adventitial macrophage accumulation impairs perivascular nerve function in mesenteric arteries with inflammatory bowel disease. Front Physiol 2023; 14:1198066. [PMID: 37342800 PMCID: PMC10278583 DOI: 10.3389/fphys.2023.1198066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 05/09/2023] [Indexed: 06/23/2023] Open
Abstract
Introduction: Inflammatory bowel disease involves aberrant immune responses and is associated with both cardiovascular disease risk and altered intestinal blood flow. However, little is known about how inflammatory bowel disease affects regulation of perivascular nerves that mediate blood flow. Previous work found perivascular nerve function is impaired in mesenteric arteries with Inflammatory bowel disease. The purpose of this study was to determine the mechanism of impaired perivascular nerve function. Methods: RNA sequencing was performed on mesenteric arteries from IL10-/- mice treated with H. hepaticus to induce disease (inflammatory bowel disease) or left non-gavaged (Control). For all other studies, Control and Inflammatory bowel disease mice received either saline or clodronate liposome injections to study the effect of macrophage depletion. Perivascular nerve function was assessed using pressure myography and electrical field stimulation. Leukocyte populations, and perivascular nerves, and adventitial neurotransmitter receptors were labeled using fluorescent immunolabeling. Results: Inflammatory bowel disease was associated with increases in macrophage-associated gene expression, and immunolabeling showed accumulation of adventitial macrophages. Clodronate liposome injection eliminated adventitial macrophages, which reversed significant attenuation of sensory vasodilation, sympathetic vasoconstriction and sensory inhibition of sympathetic constriction in inflammatory bowel disease. Acetylcholine-mediated dilation was impaired in inflammatory bowel disease and restored after macrophage depletion, but sensory dilation remained nitric oxide independent regardless of disease and/or macrophage presence. Conclusion: Altered neuro-immune signaling between macrophages and perivascular nerves in the arterial adventitia contributes to impaired vasodilation, particularly via dilatory sensory nerves. Targeting the adventitial macrophage population may help preserve intestinal blood flow in Inflammatory bowel disease patients.
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Affiliation(s)
- Elizabeth A. Grunz
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
| | - Benjamin W. Jones
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
| | - Olubodun Michael Lateef
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
| | - Sidharth Sen
- MU Institute for Data Science and Informatics, University of Missouri, Columbia, MO, United States
| | - Katie Wilkinson
- MU Institute for Data Science and Informatics, University of Missouri, Columbia, MO, United States
| | - Trupti Joshi
- MU Institute for Data Science and Informatics, University of Missouri, Columbia, MO, United States
- Department of Health Management and Informatics and Christopher S Bond Life Science Center, University of Missouri, Columbia, MO, United States
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Grunz EA, Jones BW, Sen S, Wilkenson K, Joshi T, Boerman EM. Adventitial macrophage accumulation impairs perivascular nerve function in mesenteric arteries with inflammatory bowel disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.04.535591. [PMID: 37066314 PMCID: PMC10104036 DOI: 10.1101/2023.04.04.535591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Introduction Inflammatory bowel disease (IBD) involves aberrant immune responses and is associated with both cardiovascular disease risk and altered intestinal blood flow. However, little is known about how IBD affects regulation of perivascular nerves that mediate blood flow. Previous work found perivascular nerve function is impaired in mesenteric arteries with IBD. The purpose of this study was to determine the mechanism of impaired perivascular nerve function. Methods RNA sequencing was performed on mesenteric arteries from IL10 -/- mice treated with H.hepaticus to induce disease (IBD) or left non-gavaged (Control). For all other studies, Control and IBD mice received either saline or clodronate liposome injections to study the effect of macrophage depletion. Perivascular nerve function was assessed using pressure myography and electrical field stimulation. Fluorescent immunolabeling was used to label leukocyte populations and perivascular nerves. Results IBD was associated with increased in macrophage-associated gene expression, and immunolabeling showed accumulation of adventitial macrophages. Clodronate liposome injection eliminated adventitial macrophages, which reversed significant attenuation of sensory vasodilation, sympathetic vasoconstriction and sensory inhibition of sympathetic constriction in IBD. Acetylcholine-mediated dilation was impaired in IBD and restored after macrophage depletion, but sensory dilation remained nitric oxide independent regardless of disease and/or macrophage presence. Conclusion Altered neuro-immune signaling between macrophages and perivascular nerves in the arterial adventitia contributes to impaired vasodilation, particularly via dilatory sensory nerves. Targeting the adventitial macrophage population may help preserve intestinal blood flow in IBD patients.
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Impact of Non-Pharmacological Interventions on the Mechanisms of Atherosclerosis. Int J Mol Sci 2022; 23:ijms23169097. [PMID: 36012362 PMCID: PMC9409393 DOI: 10.3390/ijms23169097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/08/2022] [Accepted: 08/10/2022] [Indexed: 11/30/2022] Open
Abstract
Atherosclerosis remains the leading cause of mortality and morbidity worldwide characterized by the deposition of lipids and fibrous elements in the form of atheroma plaques in vascular areas which are hemodynamically overloaded. The global burden of atherosclerotic cardiovascular disease is steadily increasing and is considered the largest known non-infectious pandemic. The management of atherosclerotic cardiovascular disease is increasing the cost of health care worldwide, which is a concern for researchers and physicians and has caused them to strive to find effective long-term strategies to improve the efficiency of treatments by managing conventional risk factors. Primary prevention of atherosclerotic cardiovascular disease is the preferred method to reduce cardiovascular risk. Fasting, a Mediterranean diet, and caloric restriction can be considered useful clinical tools. The protective impact of physical exercise over the cardiovascular system has been studied in recent years with the intention of explaining the mechanisms involved; the increase in heat shock proteins, antioxidant enzymes and regulators of cardiac myocyte proliferation concentration seem to be the molecular and biochemical shifts that are involved. Developing new therapeutic strategies such as vagus nerve stimulation, either to prevent or slow the disease’s onset and progression, will surely have a profound effect on the lives of millions of people.
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Norton CE, Boerman EM, Segal SS. Differential hyperpolarization to substance P and calcitonin gene-related peptide in smooth muscle versus endothelium of mouse mesenteric artery. Microcirculation 2021; 28:e12733. [PMID: 34633728 PMCID: PMC9996665 DOI: 10.1111/micc.12733] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 09/16/2021] [Accepted: 10/06/2021] [Indexed: 11/26/2022]
Abstract
OBJECTIVE We sought to define how sensory neurotransmitters substance P and calcitonin gene-related peptide (CGRP) affect membrane potential of vascular smooth muscle and endothelium. METHODS Microelectrodes recorded membrane potential of smooth muscle from pressurized mouse mesenteric arteries (diameter, ~150 µm) and in endothelial tubes. RESULTS Resting potential was similar (~ -45 mV) for each cell layer. Substance P hyperpolarized smooth muscle and endothelium ~ -15 mV; smooth muscle hyperpolarization was abolished by endothelial disruption or NO synthase inhibition. Blocking KCa channels (apamin + charybdotoxin) attenuated hyperpolarization in both cell types. CGRP hyperpolarized endothelium and smooth muscle ~ -30 mV; smooth muscle hyperpolarization was independent of endothelium. Blocking KCa channels prevented hyperpolarization to CGRP in endothelium but not smooth muscle. Inhibiting KATP channels with glibenclamide or genetic deletion of KIR 6.1 attenuated hyperpolarization in smooth muscle but not endothelium. Pinacidil (KATP channel agonist) hyperpolarized smooth muscle more than endothelium (~ -35 vs. ~ -20 mV). CONCLUSIONS Calcitonin gene-related peptide elicits greater hyperpolarization than substance P. Substance P hyperpolarizes both cell layers through KCa channels and involves endothelium-derived NO in smooth muscle. Endothelial hyperpolarization to CGRP requires KCa channels, while KATP channels mediate hyperpolarization in smooth muscle. Differential K+ channel activation in smooth muscle and endothelium through sensory neurotransmission may selectively tune mesenteric blood flow.
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Affiliation(s)
- Charles E Norton
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri, USA
| | - Erika M Boerman
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri, USA
| | - Steven S Segal
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri, USA.,Dalton Cardiovascular Research Center, Columbia, Missouri, USA
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Norton CE, Grunz-Borgmann EA, Hart ML, Jones BW, Franklin CL, Boerman EM. Role of perivascular nerve and sensory neurotransmitter dysfunction in inflammatory bowel disease. Am J Physiol Heart Circ Physiol 2021; 320:H1887-H1902. [PMID: 33710922 PMCID: PMC8163646 DOI: 10.1152/ajpheart.00037.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/03/2021] [Accepted: 03/03/2021] [Indexed: 02/06/2023]
Abstract
Inflammatory bowel disease (IBD) is associated with both impaired intestinal blood flow and increased risk of cardiovascular disease, but the functional role of perivascular nerves that control vasomotor function of mesenteric arteries (MAs) perfusing the intestine during IBD is unknown. Because perivascular sensory nerves and their transmitters calcitonin gene-related peptide (CGRP) and substance P (SP) are important mediators of both vasodilation and inflammatory responses, our objective was to identify IBD-related deficits in perivascular sensory nerve function and vascular neurotransmitter signaling. In MAs from an interleukin-10 knockout (IL-10-/-) mouse model, IBD significantly impairs electrical field stimulation (EFS)-mediated sensory vasodilation and inhibition of sympathetic vasoconstriction, despite decreased sympathetic nerve density and vasoconstriction. The MA content and EFS-mediated release of both CGRP and SP are decreased with IBD, but IBD has unique effects on each transmitter. CGRP nerve density, receptor expression, hyperpolarization, and vasodilation are preserved with IBD. In contrast, SP nerve density and receptor expression are increased, and SP hyperpolarization and vasodilation are impaired with IBD. A key finding is that blockade of SP receptors restores EFS-mediated sensory vasodilation and enhanced CGRP-mediated vasodilation in MAs from IBD but not Control mice. Together, these data suggest that an aberrant role for the perivascular sensory neurotransmitter SP and its downstream signaling in MAs underlies vascular dysfunction with IBD. We propose that with IBD, SP signaling impedes CGRP-mediated sensory vasodilation, contributing to impaired blood flow. Thus, substance P and NK1 receptors may represent an important target for treating vascular dysfunction in IBD.NEW & NOTEWORTHY Our study is the first to show that IBD causes profound impairment of sensory vasodilation and inhibition of sympathetic vasoconstriction in mesenteric arteries. This occurs alongside decreased SP-containing nerve density and increased expression of NK1 receptors for SP. In contrast, CGRP dilation, nerve density, and receptor expression are unchanged. Blocking NK1 receptors restores sensory vasodilation in MAs and increases CGRP-mediated vasodilation, indicating that SP interference with CGRP signaling may underlie impaired sensory vasodilation with IBD.
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Affiliation(s)
- Charles E Norton
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | | | - Marcia L Hart
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri
| | - Benjamin W Jones
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Craig L Franklin
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri
| | - Erika M Boerman
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
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Rybtsova N, Berezina T, Kagansky A, Rybtsov S. Can Blood-Circulating Factors Unveil and Delay Your Biological Aging? Biomedicines 2020; 8:E615. [PMID: 33333870 PMCID: PMC7765271 DOI: 10.3390/biomedicines8120615] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/09/2020] [Accepted: 12/14/2020] [Indexed: 12/15/2022] Open
Abstract
According to the World Health Organization, the population of over 60 will double in the next 30 years in the developed countries, which will enforce a further raise of the retirement age and increase the burden on the healthcare system. Therefore, there is an acute issue of maintaining health and prolonging active working longevity, as well as implementation of early monitoring and prevention of premature aging and age-related disorders to avoid early disability. Traditional indicators of biological age are not always informative and often require extensive and expensive analysis. The study of blood factors is a simple and easily accessible way to assess individual health and supplement the traditional indicators of a person's biological age with new objective criteria. With age, the processes of growth and development, tissue regeneration and repair decline; they are gradually replaced by enhanced catabolism, inflammatory cell activity, and insulin resistance. The number of senescent cells supporting the inflammatory loop rises; cellular clearance by autophagy and mitophagy slows down, resulting in mitochondrial and cellular damage and dysfunction. Monitoring of circulated blood factors not only reflects these processes, but also allows suggesting medical intervention to prevent or decelerate the development of age-related diseases. We review the age-related blood factors discussed in recent publications, as well as approaches to slowing aging for healthy and active longevity.
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Affiliation(s)
- Natalia Rybtsova
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK;
| | - Tatiana Berezina
- Department of Scientific Basis of Extreme Psychology, Moscow State University of Psychology and Education, 127051 Moscow, Russia;
| | - Alexander Kagansky
- Centre for Genomic and Regenerative Medicine, School of Biomedicine, Far Eastern Federal University, 690922 Vladivostok, Russia
| | - Stanislav Rybtsov
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh EH16 4UU, UK;
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Mittal A, Park PD, Mitchell R, Fang H, Bagher P. Comparison of Adrenergic and Purinergic Receptor Contributions to Vasomotor Responses in Mesenteric Arteries of C57BL/6J Mice and Wistar Rats. J Vasc Res 2020; 58:1-15. [PMID: 33311016 DOI: 10.1159/000511462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 09/07/2020] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION The sympathetic nervous system can modulate arteriolar tone through release of adenosine triphosphate and norepinephrine, which bind to purinergic and adrenergic receptors (ARs), respectively. The expression pattern of these receptors, as well as the composition of neurotransmitters released from perivascular nerves (PVNs), can vary both in organ systems within and across species, such as mice and rats. OBJECTIVE This study explores the function of α1A subtypes in mouse and rat third-order mesenteric arteries and investigates PVN-mediated vasoconstriction to identify which neurotransmitters are released from sympathetic PVNs. METHODS Third-order mesenteric arteries from male C57BL/6J mice and Wistar rats were isolated and mounted on a wire myograph for functional assessment. Arteries were exposed to phenylephrine (PE) and then incubated with either α1A antagonist RS100329 (RS) or α1D antagonist BMY7378, before reexposure to PE. Electrical field stimulation was performed by passing current through platinum electrodes positioned adjacent to arteries in the absence and presence of a nonspecific alpha AR blocker phentolamine and/or P2X1-specific purinergic receptor blocker NF449. RESULTS Inhibition of α1 ARs by RS revealed that PE-induced vasoconstriction is primarily mediated through α1A and that the contribution of the α1A AR is greater in rats than in mice. In the mouse model, sympathetic nerve-mediated vasoconstriction is mediated by both ARs and purinergic receptors, whereas in rats, vasoconstriction appeared to only be mediated by ARs and a nonpurinergic neurotransmitter. Further, neither model demonstrated that α1D ARs play a significant role in PE-mediated vasoconstriction. CONCLUSIONS The mesenteric arteries of male C57BL/6J mice and Wistar rats have subtle differences in the signaling mechanisms used to mediate vasoconstriction. As signaling pathways in humans under physiological and pathophysiological conditions become better defined, the current study may inform animal model selection for preclinical studies.
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Affiliation(s)
- Astha Mittal
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, Texas, USA
| | - Peter D Park
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, Texas, USA
| | - Ray Mitchell
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, Texas, USA
| | - Hanwei Fang
- Department of Microbiology and Molecular Medicine University of Geneva, Geneva, Switzerland
| | - Pooneh Bagher
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, Texas, USA,
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Aalkjær C, Nilsson H, De Mey JGR. Sympathetic and Sensory-Motor Nerves in Peripheral Small Arteries. Physiol Rev 2020; 101:495-544. [PMID: 33270533 DOI: 10.1152/physrev.00007.2020] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Small arteries, which play important roles in controlling blood flow, blood pressure, and capillary pressure, are under nervous influence. Their innervation is predominantly sympathetic and sensory motor in nature, and while some arteries are densely innervated, others are only sparsely so. Innervation of small arteries is a key mechanism in regulating vascular resistance. In the second half of the previous century, the physiology and pharmacology of this innervation were very actively investigated. In the past 10-20 yr, the activity in this field was more limited. With this review we highlight what has been learned during recent years with respect to development of small arteries and their innervation, some aspects of excitation-release coupling, interaction between sympathetic and sensory-motor nerves, cross talk between endothelium and vascular nerves, and some aspects of their role in vascular inflammation and hypertension. We also highlight what remains to be investigated to further increase our understanding of this fundamental aspect of vascular physiology.
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Affiliation(s)
| | - Holger Nilsson
- Department Physiology, Gothenburg University, Gothenburg, Sweden
| | - Jo G R De Mey
- Deptartment Pharmacology and Personalized Medicine, Maastricht University, Maastricht, The Netherlands
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Boerman EM, Segal SS. Aging alters spontaneous and neurotransmitter-mediated Ca 2+ signaling in smooth muscle cells of mouse mesenteric arteries. Microcirculation 2020; 27:e12607. [PMID: 31994289 DOI: 10.1111/micc.12607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 12/30/2019] [Accepted: 01/22/2020] [Indexed: 01/11/2023]
Abstract
OBJECTIVE Aging impairs MA dilation by reducing the ability of sensory nerves to counteract sympathetic vasoconstriction. This study tested whether altered SMC Ca2+ signals to sympathetic (NE) and sensory (CGRP) neurotransmitters underlie aging-related deficits in vasodilation. METHODS MAs from young and old mice were pressurized and loaded with Fluo-4 dye for confocal measurement of SMC Ca2+ sparks and waves. Endothelial denudation resolved the influence of ECs. SMCs were immunolabeled for RyR isoforms and compared with transcript levels for RyRs and CGRP receptor components. RESULTS SMCs from young vs old mice exhibited more spontaneous Ca2+ spark sites with no difference in Ca2+ waves. NE reduced spark sites and increased waves for both groups; addition of CGRP restored sparks and reduced waves only for young mice. Endothelial denudation attenuated Ca2+ responses to CGRP for young but not old mice, which were already attenuated, suggesting a diminished role for ECs with aging. CGRP receptor expression was similar between ages with increased serum CGRP in old mice, where RyR1 expression was replaced by RyR3. CONCLUSION With aging, we suggest that altered RyR expression in SMCs contributes to impaired ability of sensory neurotransmission to restore Ca2+ signaling underlying vasomotor control during sympathetic activation.
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Affiliation(s)
- Erika M Boerman
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA
| | - Steven S Segal
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA.,Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
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Norton CE, Jacobsen NL, Sinkler SY, Manrique-Acevedo C, Segal SS. Female sex and Western-style diet protect mouse resistance arteries during acute oxidative stress. Am J Physiol Cell Physiol 2019; 318:C627-C639. [PMID: 31891519 DOI: 10.1152/ajpcell.00342.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A Western-style diet (WD; high in fat and carbohydrates) increases vascular oxidative stress. We hypothesized that vascular cells adapt to a WD by developing resilience to oxidative stress. Male and female C57BL/6J mice (4 wk of age) were fed a control diet (CD) or a WD for 16-20 wk. Superior epigastric arteries (SEAs; diameter, ~125 µm) were isolated and pressurized for study. Basal reactive oxygen species production was greatest in SEAs from males fed the WD. During exposure to H2O2 (200 μM, 50 min), propidium iodide staining identified nuclei of disrupted endothelial cells (ECs) and smooth muscle cells (SMCs). For mice fed the CD, death of SMCs (21%) and ECs (6%) was greater (P < 0.05) in SEAs from males than females (9% and 2%, respectively). WD consumption attenuated cell death most effectively in SEAs from males. With no difference at rest, H2O2 increased intracellular Ca2+ concentration ([Ca2+]i) to the greatest extent in SEAs from males, as shown by fura 2 fluorescence. Selective disruption of the endothelium (luminal air bubble) increased [Ca2+]i and SMC death during H2O2 exposure irrespective of sex; the WD reduced both responses most effectively in males. Nonselective transient receptor potential (TRP) channel inhibition (ruthenium red, 5 μM) attenuated the rise of [Ca2+]i, as did selective inhibition of TRP vanilloid type 4 (TRPV4) channels (HC-067047, 1 μM), which also attenuated cell death. In contrast, inhibition of voltage-gated Ca2+ channels (diltiazem, 50 μM) was without effect. Thus, for resistance arteries during acute oxidative stress: 1) ECs are more resilient than (and can protect) SMCs, 2) vessels from females are inherently more resilient than those from males, and 3) a WD increases vascular resilience by diminishing TRPV4 channel-dependent Ca2+ entry.
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Affiliation(s)
- Charles E Norton
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Nicole L Jacobsen
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Shenghua Y Sinkler
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Camila Manrique-Acevedo
- Department of Medicine, University of Missouri, Columbia, Missouri.,Research Services, Harry S Truman Memorial Veterans Hospital, Columbia, Missouri.,Dalton Cardiovascular Research Center, Columbia, Missouri
| | - Steven S Segal
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri.,Dalton Cardiovascular Research Center, Columbia, Missouri
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Michalska JM, Ran C, Fourier C, Steinberg A, Sjöstrand C, Waldenlind E, Belin AC. Involvement of CGRP receptor RAMP1 in cluster headache: A Swedish case-control study. CEPHALALGIA REPORTS 2019. [DOI: 10.1177/2515816319879886] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Background: Increased levels of the potent vasodilator calcitonin gene-related peptide (CGRP) have been found in ipsilateral jugular vein blood during the active phase of cluster headache (CH) and this is hypothesized to cause distinctive vasodilation. The receptor activity-modifying protein 1 (RAMP1) is part of the CGRP receptor complex responsible for ligand binding and specificity and therefore constitutes a promising candidate gene for CH. The aim of this study was to investigate the possible genetic association of RAMP1 with CH in Sweden, with focus on two RAMP1 single nucleotide polymorphisms, rs3754701 and rs7590387, and quantify RAMP1 mRNA expression levels in biological tissue from CH patients and controls. Methods: rs3754701 and rs7590387 were genotyped by quantitative polymerase chain reaction (qPCR) in 542 CH patients and 585 control subjects. RAMP1 mRNA expression was determined by reverse transcription qPCR in tissue from 12 CH patients and 12 controls. Results: We identified a significant difference between the CH patient and control groups for rs3754701 ( p = 0.0088). In addition, RAMP1 mRNA expression was enhanced in primary fibroblasts from CH patients compared to controls ( p = 0.0073). Conclusion: The association between rs3754701 and CH and the enhanced RAMP1 mRNA expression in CH patients support the hypothesis that CGRP and its receptor component RAMP1 are involved in CH pathophysiology.
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Affiliation(s)
- Julia M Michalska
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Caroline Ran
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Carmen Fourier
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Anna Steinberg
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Department of Neurology, Karolinska University Hospital, Stockholm, Sweden
| | - Christina Sjöstrand
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Department of Neurology, Karolinska University Hospital, Stockholm, Sweden
| | - Elisabet Waldenlind
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Department of Neurology, Karolinska University Hospital, Stockholm, Sweden
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Norton CE, Sinkler SY, Jacobsen NL, Segal SS. Advanced age protects resistance arteries of mouse skeletal muscle from oxidative stress through attenuating apoptosis induced by hydrogen peroxide. J Physiol 2019; 597:3801-3816. [PMID: 31124136 DOI: 10.1113/jp278255] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 05/23/2019] [Indexed: 01/16/2023] Open
Abstract
KEY POINTS Vascular oxidative stress increases with advancing age. We hypothesized that resistance vessels develop resilience to oxidative stress to protect functional integrity and tested this hypothesis by exposing isolated pressurized superior epigastric arteries (SEAs) of old and young mice to H2 O2 . H2 O2 -induced death was greater in smooth muscle cells (SMCs) than endothelial cells (ECs) and lower in SEAs from old vs. young mice; the rise in vessel wall [Ca2+ ]i induced by H2 O2 was attenuated with ageing, as was the decline in noradrenergic vasoconstriction; genetic deletion of IL-10 mimicked the effects of advanced age on cell survival. Inhibiting NO synthase or scavenging peroxynitrite reduced SMC death; endothelial denudation or inhibiting gap junctions increased SMC death; delocalization of cytochrome C activated caspases 9 and 3 to induce apoptosis. Vascular cells develop resilience to H2 O2 during ageing by preventing Ca2+ overload and endothelial integrity promotes SMC survival. ABSTRACT Advanced age is associated with elevated oxidative stress and can protect the endothelium from cell death induced by H2 O2 . Whether such protection occurs for intact vessels or differs between smooth muscle cell (SMC) and endothelial cell (EC) layers is unknown. We tested the hypothesis that ageing protects SMCs and ECs during acute exposure to H2 O2 (200 µm, 50 min). Mouse superior epigastric arteries (SEAs; diameter, ∼150 µm) were isolated and pressurized to 100 cmH2 O at 37˚C. For SEAs from young (4 months) mice, H2 O2 killed 57% of SMCs and 11% of ECs in males vs. 8% and 2%, respectively, in females. Therefore, SEAs from males were studied to resolve the effect of ageing and experimental interventions. For old (24 months) mice, SMC death was reduced to 10% with diminished accumulation of [Ca2+ ]i in the vessel wall during H2 O2 exposure. In young mice, genetic deletion of IL-10 mimicked the protective effect of ageing on cell death and [Ca2+ ]i accumulation. Whereas endothelial denudation or gap junction inhibition (carbenoxolone; 100 µm) increased SMC death, inhibiting NO synthase (l-NAME, 100 µm) or scavenging peroxynitrite (FeTPPS, 5 µm) reduced SMC death along with [Ca2+ ]i . Despite NO toxicity via peroxynitrite formation, endothelial integrity protects SMCs. Caspase inhibition (Z-VAD-FMK, 50 µm) attenuated cell death with immunostaining for annexin V, cytochrome C, and caspases 3 and 9 pointing to induction of intrinsic apoptosis during H2 O2 exposure. We conclude that advanced age reduces Ca2+ influx that triggers apoptosis, thereby promoting resilience of the vascular wall during oxidative stress.
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Affiliation(s)
- Charles E Norton
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, 65212, USA
| | - Shenghua Y Sinkler
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, 65212, USA
| | - Nicole L Jacobsen
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, 65212, USA
| | - Steven S Segal
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, 65212, USA.,Dalton Cardiovascular Research Center, Columbia, MO, 65211, USA
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14
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Søndergaard AM, Overgaard CB, Mazur A, Postnov DD, Matchkov VV, Aalkjaer C. Rat mesenteric small artery neurogenic dilatation is predominantly mediated by β 1 -adrenoceptors in vivo. J Physiol 2019; 597:1819-1831. [PMID: 30693527 DOI: 10.1113/jp277368] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Accepted: 01/23/2019] [Indexed: 01/19/2023] Open
Abstract
KEY POINTS The prevailing dogma about neurogenic regulation of vascular tone consists of major vasodilatation caused by CGRP (and possibly substance P) released from sensory-motor nerves and vasoconstriction caused by noradrenaline, ATP and neuropeptode Y release from sympathetic nerves. Most studies on perivascular nerve-mediated vasodilatation are made in vitro. In the present study, we provide evidence indicating that in vivo electrical perivascular nerve stimulation in rat mesenteric small arteries causes a large β1-adrenoceptor-mediated vasodilatation, which contrasts with a smaller vasodilatation caused by endogenous CGRP that is only visible after inhibition of Y1 NPY receptors. ABSTRACT Mesenteric arteries are densely innervated and the nerves are important regulators of vascular tone and hence blood pressure and blood flow. Perivascular sensory-motor nerves have been shown to cause vasodilatation in vitro. However, less is known about their function in vivo. Male Wistar rats (10-12 weeks old; n = 72) were anaesthetized with ketamine (3 mg kg-1 ) and xylazine (0.75 mg kg-1 ) or pentobarbital (60 mg kg-1 ). After a laparotomy, a section of second-order mesenteric artery was visualized in an organ bath after minimal removal of perivascular adipose tissue. The effects of electrical field stimulation (EFS) and drugs on artery diameter and blood flow were recorded with intravital microscopy and laser speckle imaging. EFS caused vasodilatation in arteries constricted with 1 μm U46619 in the presence of 140 μm suramin and 1 μm prazosin. The vasodilatation was inhibited by 1 μm tetrodotoxin and 5 μm guanethidine, although not by the 1 μm of the CGRP receptor antagonist BIBN4096bs. In the presence of 0.3 μm Y1 receptor antagonist BIBP3226, BIBN4096bs partly inhibited the vasodilatation. Atenolol at a concentration 1 μm inhibited the vasodilatation, whereas 0.1 μm of the β2 -adrenoceptor selective antagonist ICI-118,551 had no effect. Increasing the extracellular [K+ ] to 20 mm caused vasodilatation but was converted to vasoconstriction in the presence of 1 μm BIBN4096bs, and constriction to 30 mm potassium was potentiated by BIBN4096bs. Atenolol but not BIBN4096bs increased contraction to EFS in the absence of suramin and prazosin. In mesenteric small arteries of anaesthetized rats, EFS failed to stimulate major dilatation via sensory-motor nerves but induced sympathetic β1 -adrenoceptor-mediated dilatation.
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Affiliation(s)
| | | | - Aleksandra Mazur
- Department of Biomedicine, Membranes, University of Aarhus, Aarhus, Denmark
| | - Dmitry D Postnov
- Department of Biomedical Sciences, University of Copenhagen, Denmark.,Neurophotonics Center, Boston University, Boston, MA, USA
| | | | - Christian Aalkjaer
- Department of Biomedicine, Membranes, University of Aarhus, Aarhus, Denmark.,Department of Biomedical Sciences, University of Copenhagen, Denmark
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15
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Corliss BA, Mathews C, Doty R, Rohde G, Peirce SM. Methods to label, image, and analyze the complex structural architectures of microvascular networks. Microcirculation 2019; 26:e12520. [PMID: 30548558 PMCID: PMC6561846 DOI: 10.1111/micc.12520] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 10/31/2018] [Accepted: 11/26/2018] [Indexed: 12/30/2022]
Abstract
Microvascular networks play key roles in oxygen transport and nutrient delivery to meet the varied and dynamic metabolic needs of different tissues throughout the body, and their spatial architectures of interconnected blood vessel segments are highly complex. Moreover, functional adaptations of the microcirculation enabled by structural adaptations in microvascular network architecture are required for development, wound healing, and often invoked in disease conditions, including the top eight causes of death in the Unites States. Effective characterization of microvascular network architectures is not only limited by the available techniques to visualize microvessels but also reliant on the available quantitative metrics that accurately delineate between spatial patterns in altered networks. In this review, we survey models used for studying the microvasculature, methods to label and image microvessels, and the metrics and software packages used to quantify microvascular networks. These programs have provided researchers with invaluable tools, yet we estimate that they have collectively attained low adoption rates, possibly due to limitations with basic validation, segmentation performance, and nonstandard sets of quantification metrics. To address these existing constraints, we discuss opportunities to improve effectiveness, rigor, and reproducibility of microvascular network quantification to better serve the current and future needs of microvascular research.
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Affiliation(s)
- Bruce A Corliss
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Corbin Mathews
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Richard Doty
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Gustavo Rohde
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
| | - Shayn M Peirce
- Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia
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16
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Boerman EM, Sen S, Shaw RL, Joshi T, Segal SS. Gene expression profiles of ion channels and receptors in mouse resistance arteries: Effects of cell type, vascular bed, and age. Microcirculation 2018; 25:e12452. [PMID: 29577514 PMCID: PMC5949082 DOI: 10.1111/micc.12452] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 03/19/2018] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Receptors and ion channels of smooth muscle cells (SMCs) and endothelial cells (ECs) are integral to the regulation of vessel diameter and tissue blood flow. Physiological roles of ion channels and receptors in skeletal muscle and mesenteric arteries have been identified; however, their gene expression profiles are undefined. We tested the hypothesis that expression profiles for ion channels and receptors governing vascular reactivity vary with cell type, vascular bed, and age. METHODS Mesenteric and superior epigastric arteries were dissected from Old (24-26 months) and Young (3-6 months) C57BL/6J mice. ECs and SMCs were collected for analysis with custom qRT-PCR arrays to determine expression profiles of 80 ion channel and receptor genes. Bioinformatics analyses were applied to gain insight into functional interactions. RESULTS We identified 68 differences in gene expression with respect to cell type, vessel type, and age. Heat maps illustrate differential expression, and distance matrices predict patterns of coexpression. Gene networks based upon protein-protein interaction datasets and KEGG pathways illustrate biological processes affected by specific differences in gene expression. CONCLUSIONS Differences in gene expression profiles are most pronounced between microvascular ECs and SMCs with subtle variations between vascular beds and age groups.
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Affiliation(s)
- Erika M. Boerman
- Medical Pharmacology and Physiology, School of Medicine, University of Missouri, Columbia, MO 65212
| | - Sidharth Sen
- MU Informatics Institute, University of Missouri, Columbia, MO 65211
| | - Rebecca L. Shaw
- Medical Pharmacology and Physiology, School of Medicine, University of Missouri, Columbia, MO 65212
| | - Trupti Joshi
- MU Informatics Institute, University of Missouri, Columbia, MO 65211
- Health Management and Informatics and Office of Research, School of Medicine, University of Missouri, Columbia, MO 65212
- Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO 65211
| | - Steven S. Segal
- Medical Pharmacology and Physiology, School of Medicine, University of Missouri, Columbia, MO 65212
- Dalton Cardiovascular Research Center, Columbia, MO 65211
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17
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Norton CE, Segal SS. Calcitonin gene-related peptide hyperpolarizes mouse pulmonary artery endothelial tubes through K ATP channel activation. Am J Physiol Lung Cell Mol Physiol 2018. [PMID: 29543503 DOI: 10.1152/ajplung.00044.2018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The sensory neurotransmitter calcitonin gene-related peptide (CGRP) is associated with vasodilation of systemic arteries through activation of ATP-sensitive K+ (KATP) channels in smooth muscle cells (SMCs); however, its effects on endothelial cell (EC) membrane potential ( Vm) are unresolved. In pulmonary arteries (PAs) of C57BL/6J mice, we questioned whether CGRP would hyperpolarize ECs as well as SMCs. Intact PAs were isolated and immunostained for CGRP to confirm sensory innervation; vessel segments (1-2 mm long, ∼150 µm diameter) with intact or denuded endothelium were cannulated and pressurized to 16 cmH2O at 37°C. Increasing concentrations (10-10-10-6 M) of CGRP progressively dilated PAs preconstricted with UTP (10-5 M); SMCs hyperpolarized similarly (Δ Vm ∼20 mV) before and after endothelial denudation. To study native intact PA ECs, SMCs were dissociated to isolate endothelial tubes, and their integrity was confirmed by vital dye uptake, nuclear staining, and reproducible electrical and intracellular Ca2+ responses to acetylcholine (10-5 M) over 2 h. Increasing [CGRP] hyperpolarized ECs in a manner similar to SMCs, with each cell layer demonstrating robust immunostaining for CGRP receptor proteins. Increasing concentrations (10-10-10-6 M) of pinacidil, a KATP channel agonist, resulted in progressive hyperpolarization of SMCs of intact PAs (Δ Vm ∼30 mV), which was blocked by glibenclamide (10-6 M), as was hyperpolarization of ECs and SMCs to CGRP. Inhibition of protein kinase A with protein kinase inhibitor (10-5 M) also inhibited hyperpolarization to CGRP. We demonstrate [CGRP]-dependent hyperpolarization of ECs for the first time while validating freshly isolated PA endothelial tubes as an experimental model. Redundant electrical signaling to CGRP in ECs and SMCs implies an integral role for KATP channels in PA dilation.
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Affiliation(s)
- Charles E Norton
- Department of Medical Pharmacology and Physiology, University of Missouri , Columbia, Missouri
| | - Steven S Segal
- Department of Medical Pharmacology and Physiology, University of Missouri , Columbia, Missouri.,Dalton Cardiovascular Research Center , Columbia, Missouri
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18
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Sheng Y, Zhu L. The crosstalk between autonomic nervous system and blood vessels. INTERNATIONAL JOURNAL OF PHYSIOLOGY, PATHOPHYSIOLOGY AND PHARMACOLOGY 2018; 10:17-28. [PMID: 29593847 PMCID: PMC5871626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 02/24/2018] [Indexed: 06/08/2023]
Abstract
The autonomic nervous system (ANS), comprised of two primary branches, sympathetic and parasympathetic nervous system, plays an essential role in the regulation of vascular wall contractility and tension. The sympathetic and parasympathetic nerves work together to balance the functions of autonomic effector organs. The neurotransmitters released from the varicosities in the ANS can regulate the vascular tone. Norepinephrine (NE), adenosine triphosphate (ATP) and Neuropeptide Y (NPY) function as vasoconstrictors, whereas acetylcholine (Ach) and calcitonin gene-related peptide (CGRP) can mediate vasodilation. On the other hand, vascular factors, such as endothelium-derived relaxing factor nitric oxide (NO), and constriction factor endothelin, play an important role in the autonomic nervous system in physiologic conditions. Endothelial dysfunction and inflammation are associated with the sympathetic nerve activity in the pathological conditions, such as hypertension, heart failure, and diabetes mellitus. The dysfunction of the autonomic nervous system could be a risk factor for vascular diseases and the overactive sympathetic nerve is detrimental to the blood vessel. In this review, we summarize findings concerning the crosstalk between ANS and blood vessels in both physiological and pathological conditions and hope to provide insight into the development of therapeutic interventions of vascular diseases.
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Affiliation(s)
- Yulan Sheng
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology of Jiangsu Province, State Key Laboratory of Radiation Medicine and Protection, Soochow UniversitySuzhou 215123, China
| | - Li Zhu
- Cyrus Tang Hematology Center, Collaborative Innovation Center of Hematology of Jiangsu Province, State Key Laboratory of Radiation Medicine and Protection, Soochow UniversitySuzhou 215123, China
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19
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Behringer EJ. Calcium and electrical signaling in arterial endothelial tubes: New insights into cellular physiology and cardiovascular function. Microcirculation 2018; 24. [PMID: 27801542 DOI: 10.1111/micc.12328] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 10/25/2016] [Indexed: 12/23/2022]
Abstract
The integral role of the endothelium during the coordination of blood flow throughout vascular resistance networks has been recognized for several decades now. Early examination of the distinct anatomy and physiology of the endothelium as a signaling conduit along the vascular wall has prompted development and application of an intact endothelial "tube" study model isolated from rodent skeletal muscle resistance arteries. Vasodilatory signals such as increased endothelial cell (EC) Ca2+ ([Ca2+ ]i ) and hyperpolarization take place in single ECs while shared between electrically coupled ECs through gap junctions up to distances of millimeters (≥2 mm). The small- and intermediate-conductance Ca2+ activated K+ (SKCa /IKCa or KCa 2.3/KCa 3.1) channels function at the interface of Ca2+ signaling and hyperpolarization; a bidirectional relationship whereby increases in [Ca2+ ]i activate SKCa /IKCa channels to produce hyperpolarization and vice versa. Further, the spatial domain of hyperpolarization among electrically coupled ECs can be finely tuned via incremental modulation of SKCa /IKCa channels to balance the strength of local and conducted electrical signals underlying vasomotor activity. Multifunctional properties of the voltage-insensitive SKCa /IKCa channels of resistance artery endothelium may be employed for therapy during the aging process and development of vascular disease.
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Affiliation(s)
- Erik J Behringer
- Department of Basic Sciences, Loma Linda University, Loma Linda, CA, USA
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20
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Burnstock G. Purinergic Signaling in the Cardiovascular System. Circ Res 2017; 120:207-228. [PMID: 28057794 DOI: 10.1161/circresaha.116.309726] [Citation(s) in RCA: 259] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 11/21/2016] [Accepted: 11/23/2016] [Indexed: 02/07/2023]
Abstract
There is nervous control of the heart by ATP as a cotransmitter in sympathetic, parasympathetic, and sensory-motor nerves, as well as in intracardiac neurons. Centers in the brain control heart activities and vagal cardiovascular reflexes involve purines. Adenine nucleotides and nucleosides act on purinoceptors on cardiomyocytes, AV and SA nodes, cardiac fibroblasts, and coronary blood vessels. Vascular tone is controlled by a dual mechanism. ATP, released from perivascular sympathetic nerves, causes vasoconstriction largely via P2X1 receptors. Endothelial cells release ATP in response to changes in blood flow (via shear stress) or hypoxia, to act on P2 receptors on endothelial cells to produce nitric oxide, endothelium-derived hyperpolarizing factor, or prostaglandins to cause vasodilation. ATP is also released from sensory-motor nerves during antidromic reflex activity, to produce relaxation of some blood vessels. Purinergic signaling is involved in the physiology of erythrocytes, platelets, and leukocytes. ATP is released from erythrocytes and platelets, and purinoceptors and ectonucleotidases are expressed by these cells. P1, P2Y1, P2Y12, and P2X1 receptors are expressed on platelets, which mediate platelet aggregation and shape change. Long-term (trophic) actions of purine and pyrimidine nucleosides and nucleotides promote migration and proliferation of vascular smooth muscle and endothelial cells via P1 and P2Y receptors during angiogenesis, vessel remodeling during restenosis after angioplasty and atherosclerosis. The involvement of purinergic signaling in cardiovascular pathophysiology and its therapeutic potential are discussed, including heart failure, infarction, arrhythmias, syncope, cardiomyopathy, angina, heart transplantation and coronary bypass grafts, coronary artery disease, diabetic cardiomyopathy, hypertension, ischemia, thrombosis, diabetes mellitus, and migraine.
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Affiliation(s)
- Geoffrey Burnstock
- From the Autonomic Neuroscience Institute, Royal Free and University College Medical School, London, United Kingdom.
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21
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Sinkler SY, Fernando CA, Segal SS. Differential α-adrenergic modulation of rapid onset vasodilatation along resistance networks of skeletal muscle in old versus young mice. J Physiol 2016; 594:6987-7004. [PMID: 27501249 DOI: 10.1113/jp272409] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 07/27/2016] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS Rapid onset vasodilatation (ROV) initiates functional hyperaemia upon skeletal muscle contraction and is attenuated during ageing via α-adrenoreceptor (αAR) stimulation, but it is unknown where this effect predominates in resistance networks. In gluteus maximus muscles of young (4 months) and old (24 months) male C57BL/6 mice, tetanic contraction while observing feed arteries and arterioles initiated ROV, which increased with contraction duration, peaked later in upstream versus downstream vessel branches and was attenuated throughout networks with advanced age. With no effect on muscle force production, inhibiting αARs improved ROV in old mice while activating αARs attenuated ROV in young mice. Modulating ROV through αARs was greater in upstream feed arteries and arterioles compared to downstream arterioles, with α2 ARs more effective than α1 ARs. ROV is coordinated along resistance networks and modulated differentially between young and old mice via αARs; with advanced age, attenuated dilatation of upstream branches will restrict muscle blood flow. ABSTRACT Rapid onset vasodilatation (ROV) in skeletal muscle is attenuated during advanced age via α-adrenoreceptor (αAR) activation, but it is unknown where such effects predominate in the resistance vasculature. Studying the gluteus maximus muscle (GM) of anaesthetized young (4 months) and old (24 months) male C57BL/6 mice, we tested the hypothesis that attenuation of ROV during advanced age is most effective in proximal branches of microvascular resistance networks. Diameters of a feed artery (FA) and first- (1A), second- (2A) and third- (3A) order arterioles were studied in response to single tetanic contractions (100 Hz, 100-1000 ms). ROV began within 1 s and peaked sooner in 2A and 3A (∼3 s) than in 1A or FA (∼4 s). Relative amplitudes of dilatation increased with contraction duration and with vessel branch order (FA<1A<2A<3A). In old mice, attenuation of ROV was greater in FA and 1A compared to 2A and 3A. With no effect on muscle force production, inhibiting αARs (phentolamine; 10-6 m) improved ROV in FA and 1A of old mice while subthreshold stimulation of αARs in young mice (noradrenaline; 10-9 m) depressed ROV most effectively in FA and 1A. In young mice, stimulating α1 ARs (phenylephrine; 10-7 m) and α2 ARs (UK 14304; 10-7 m) attenuated ROV primarily in FA. In old mice, inhibiting α2 ARs (rauwolscine; 10-7 m) restored ROV more effectively in FA and 1A than did inhibiting α1 ARs (prazosin; 10-8 m). We conclude that, with temporal and spatial coordination along resistance networks, attenuation of ROV with advanced age is most effective in proximal branches via constitutive activation of α2 ARs.
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Affiliation(s)
- Shenghua Y Sinkler
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, 65212, USA
| | - Charmain A Fernando
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, 65212, USA
| | - Steven S Segal
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, 65212, USA.,Dalton Cardiovascular Research Center, Columbia, MO, 65211, USA
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22
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Mann GE. Cardiovascular and skeletal muscle ageing: consequences for longevity. J Physiol 2016; 594:1961-3. [PMID: 27079628 PMCID: PMC4933101 DOI: 10.1113/jp270578] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 02/04/2016] [Indexed: 01/16/2023] Open
Affiliation(s)
- Giovanni E Mann
- Cardiovascular Division, BHF Centre of Research Excellence, Faculty of Life & Health Sciences, King's College London, 150 Stamford Street, London, SE1 9NH, UK
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