11,052 results match your criteria American Journal Of Physiology-Heart And Circulatory Physiology[Journal]


Impact of breakthrough COVID-19 cases during the Omicron wave on vascular health and cardiac autonomic function in young adults.

Am J Physiol Heart Circ Physiol 2022 May 20. Epub 2022 May 20.

Department of Kinesiology, The University of Texas at Arlington, Arlington, Texas, United States.

We and others have previously shown that COVID-19 results in vascular and autonomic impairments in young adults. However, the newest variant of COVID-19 (Omicron) appears to have less severe complications. Therefore, we investigated whether recent breakthrough infection with COVID-19 during the Omicron wave impacts cardiovascular health in young adults. Read More

View Article and Full-Text PDF

Advancement toward predicting maternal vascular adaptations to pregnancy.

Am J Physiol Heart Circ Physiol 2022 May 20. Epub 2022 May 20.

Department of Pharmaceutical Sciences, University of North Texas Health Science Center, Fort Worth, Texas, United States.

View Article and Full-Text PDF

Cytokine receptor gp130 promotes postnatal proliferation of cardiomyocytes required for the normal functional development of the heart.

Am J Physiol Heart Circ Physiol 2022 May 20. Epub 2022 May 20.

Department of Molecular Pharmacology, Shinshu University School of Medicine, Nagano, Japan.

Mammalian ventricular cardiomyocytes are premature at birth and exhibit substantial phenotypic changes before weaning. Mouse ventricular myocytes undergo cell division several times after birth; however, the regulatory mechanisms and roles of cardiomyocyte division in postnatal heart development remain unclear. Here, we investigated the physiological role of gp130, the main subunit of multifunctional receptors for the IL-6 family of cytokines, in postnatal cardiomyocyte proliferation. Read More

View Article and Full-Text PDF

Piezo1 regulates shear-dependent nitric oxide production in human erythrocytes.

Am J Physiol Heart Circ Physiol 2022 May 13. Epub 2022 May 13.

Biorheology Research Laboratory, Menzies Health Institute Queensland, Australia.

Mature circulating red blood cells (RBC) are classically viewed as passive participants in circulatory function, given erythroblasts eject their organelles during maturation. Endogenous production of nitric oxide (NO) and its effects are of particular significance; however, the integration between RBC sensation of the local environment and subsequent activation of mechano-sensitive signaling networks that generate NO remain poorly understood. The present study investigated endogenous NO-production via the RBC-specific nitric oxide synthase-isoform (RBC-NOS), connecting membrane strain with intracellular enzymatic processes. Read More

View Article and Full-Text PDF

Reliability of Heart Rate Variability During Stable and Disrupted Polysomnographic Sleep.

Am J Physiol Heart Circ Physiol 2022 May 13. Epub 2022 May 13.

Department of Microbiology & Cell Biology, Montana State University, Bozeman, MT, United States.

Heart rate variability (HRV) is commonly used within sleep and cardiovascular research, yet HRV reliability across various sleep stages remains equivocal. The present study examined the reliability of frequency- and time-domain HRV within stage II (N2), slow wave (SWS), and rapid eye movement (REM) sleep during both stable and disrupted sleep. We hypothesized that high-frequency (HF) HRV would be reliable in all three sleep stages, low-frequency (LF) HRV would be reliable during N2 and SWS, and that disrupted sleep via spontaneous cortical arousals would decrease HRV reliability. Read More

View Article and Full-Text PDF

Myocardial Injury, Troponin Release and Cardiomyocyte Death in Brief Ischemia, Failure and Ventricular Remodeling.

Authors:
John M Canty

Am J Physiol Heart Circ Physiol 2022 May 13. Epub 2022 May 13.

VA WNY Health Care System, the Departments of Medicine, Physiology & Biophysics, Biomedical Engineering and The Clinical and Translational Research Center of the University at Buffalo, Buffalo, NY, United States.

Troponin released from irreversibly injured myocytes is the gold standard biomarker for the rapid identification of an acute coronary syndrome. In acute myocardial infarction, necrotic cell death is characterized by sarcolemmal disruption in response to a critical level of energy depletion after more than 15-minutes of ischemia. While troponin I and T are highly specific for cardiomyocyte death, high-sensitivity assays have demonstrated that measurable circulating levels of troponin are present in the majority of normal subjects. Read More

View Article and Full-Text PDF

Hyperspectral Wide-Field-Of-View Imaging to Study Dynamic Microcirculatory Changes During Hypoxia.

Am J Physiol Heart Circ Physiol 2022 May 6. Epub 2022 May 6.

Department of Bioengineering, University of California San Diego, La Jolla, CA, United States.

Objective: Hyperspectral imaging (HSI) provides a fast, reliable, and non-invasive way the study vascular microcirculation in animal models. Rapid hyperspectral imaging of large portions of the microcirculatory preparation is critical for understanding the function and regulation of vascular microcirculatory networks.

Methods: This report presents the application of an off-the-shelf, benchtop, HSI linear scanning system to acquire larger field-of-view images of microcirculatory preparations. Read More

View Article and Full-Text PDF

Arteriolar dysgenesis in ischemic, regenerating skeletal muscle revealed by automated micro-morphometry, computational modeling, and perfusion analysis.

Am J Physiol Heart Circ Physiol 2022 May 6. Epub 2022 May 6.

Robarts Research Institute, University of Western Ontario, London, Ontario, Canada.

Rebuilding the local vasculature is central to restoring the health of muscles subjected to ischemic injury. Arteriogenesis yields remodeled collateral arteries that circumvent the obstruction, and angiogenesis produces capillaries to perfuse the regenerating myofibers. However, the vital intervening network of arterioles that feed the regenerated capillaries is poorly understood and an investigative challenge. Read More

View Article and Full-Text PDF

Integrin α11β1 and syndecan-4 dual receptor ablation attenuate cardiac hypertrophy in the pressure overloaded heart.

Am J Physiol Heart Circ Physiol 2022 Jun 6;322(6):H1057-H1071. Epub 2022 May 6.

Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway.

Pathological myocardial hypertrophy in response to an increase in left ventricular (LV) afterload may ultimately lead to heart failure. Cell surface receptors bridge the interface between the cell and the extracellular matrix (ECM) in cardiac myocytes and cardiac fibroblasts and have been suggested to be important mediators of pathological myocardial hypertrophy. We identify for the first time that integrin α11 (α11) is preferentially upregulated among integrin β1 heterodimer-forming α-subunits in response to increased afterload induced by aortic banding (AB) in wild-type (WT) mice. Read More

View Article and Full-Text PDF

α-Tubulin acetylation on lysine 40 controls cardiac glucose uptake.

Am J Physiol Heart Circ Physiol 2022 Jun 29;322(6):H1032-H1043. Epub 2022 Apr 29.

Institut de Recherche Expérimentale et Clinique, Pole of Cardiovascular Research, Université catholique de Louvain, Brussels, Belgium.

Our group previously demonstrated that an excess of nutrients, as observed in diabetes, provokes an increase in cardiac protein acetylation responsible for a reduced insulin-stimulated translocation of the glucose transporter GLUT4 to the plasma membrane. The acetylated proteins involved in this event have yet not been identified. α-Tubulin is a promising candidate as a major cytoskeleton component involved, among other things, in the translocation of GLUT4-containing vesicles from their intracellular pools toward the plasma membrane. Read More

View Article and Full-Text PDF

Effect of oral hormonal contraceptive pill use on the hemodynamic response to the cold pressor test.

Am J Physiol Heart Circ Physiol 2022 Jun 29;322(6):H1072-H1079. Epub 2022 Apr 29.

Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri.

Acute increases in sympathetic nervous system activity (SNA) often elicit peripheral vasoconstriction and increases in blood pressure (BP). Given sympathetic support of BP is modulated by ovarian sex hormones (e.g. Read More

View Article and Full-Text PDF

Evaluation of early bilateral ovariectomy in mice as a model of left heart disease.

Am J Physiol Heart Circ Physiol 2022 Jun 29;322(6):H1080-H1085. Epub 2022 Apr 29.

Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee.

Postmenopausal women tend to have worse cardiovascular outcomes in a manner that is associated with osteoporosis severity. In this study, we performed the first evaluation of the left ventricle and aortic valve phenotype of ovariectomized mice aged on Western diet to 1 yr. Disease was monitored in vivo using echocardiography and dual X-ray absorptiometry imaging and ex vivo using quantitative histological and immunostaining analysis. Read More

View Article and Full-Text PDF

Subcutaneous B16 melanoma impairs intrinsic pressure generation and relaxation of the heart, which are not restored by short-term voluntary exercise in mice.

Am J Physiol Heart Circ Physiol 2022 Jun 29;322(6):H1044-H1056. Epub 2022 Apr 29.

Laboratory of Animal Physiology, Department of Biology, University of Turku, Turku, Finland.

The aim of this study was to investigate whether subcutaneous melanoma impairs intrinsic cardiac function and hypoxia tolerance in mice. In addition, it was investigated whether these changes could be prevented by voluntary wheel-running exercise. The roles of different molecular pathways were also analyzed. Read More

View Article and Full-Text PDF

The role of adipose tissue dysfunction in PM-induced vascular pathology.

Am J Physiol Heart Circ Physiol 2022 Jun;322(6):H971-H972

Department of Nutritional Sciences, College of Human Sciences, Texas Tech University, Lubbock, Texas.

View Article and Full-Text PDF

Reply to Della Guardia and Shin.

Authors:
Petra Haberzettl

Am J Physiol Heart Circ Physiol 2022 Jun;322(6):H973-H974

Division of Environmental Medicine, Christina Lee Brown Envirome Institute, Diabetes and Obesity Center, University of Louisville, Louisville, Kentucky.

View Article and Full-Text PDF

Predicting pregnancy specific uterine vascular reactivity: A data driven computational model of shear-dependent, myogenic, and mechanical radial artery features.

Am J Physiol Heart Circ Physiol 2022 Apr 22. Epub 2022 Apr 22.

Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand.

The entire maternal circulation adapts to pregnancy, and this adaption is particularly extensive in the uterine circulation where the major vessels double in size to facilitate an approximately 15-fold increase in blood supply to this organ over the course of pregnancy. Several factors may play a role in both the remodelling and biomechanical function of the uterine vasculature including the paracrine microenvironment, passive properties of the vessel wall, and active components of vascular function (incorporating the myogenic response and response to shear stress induced by intravascular blood flow). However, the interplay between these factors, and how this plays out in an organ-specific manner to induce the extent of remodelling observed in the uterus is not well understood. Read More

View Article and Full-Text PDF

Low-Dose Morphine Reduces Tolerance to Central Hypovolemia in Healthy Adults Without Affecting Muscle Sympathetic Outflow.

Am J Physiol Heart Circ Physiol 2022 Apr 22. Epub 2022 Apr 22.

Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, United States.

Hemorrhage is a leading cause of preventable battlefield and civilian trauma deaths. Low-dose (i.e. Read More

View Article and Full-Text PDF

A step toward a unifying preclinical model of dilated cardiomyopathy.

Am J Physiol Heart Circ Physiol 2022 Jun 15;322(6):H1028-H1031. Epub 2022 Apr 15.

Department of Pharmacology, Dalhousie University, Saint John, New Brunswick, Canada.

View Article and Full-Text PDF

expression in the adult mouse heart modulates Na influx in myocytes and reveals a mechanistic link between Na entry and diastolic function.

Am J Physiol Heart Circ Physiol 2022 Jun 8;322(6):H975-H993. Epub 2022 Apr 8.

Department of Physiology, New York Medical College, Valhalla, New York.

Voltage-gated sodium channels (VGSCs) are macromolecular assemblies composed of a number of proteins regulating channel conductance and properties. VGSCs generate Na current () in myocytes and play fundamental roles in excitability and impulse conduction in the heart. Moreover, VGSCs condition mechanical properties of the myocardium, a process that appears to involve the late component of . Read More

View Article and Full-Text PDF

Reverse is a complicated direction.

Am J Physiol Heart Circ Physiol 2022 May 8;322(5):H842-H843. Epub 2022 Apr 8.

Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, New York.

View Article and Full-Text PDF

Short-term salicylate treatment improves microvascular endothelium-dependent dilation in young adults with major depressive disorder.

Am J Physiol Heart Circ Physiol 2022 May 1;322(5):H880-H889. Epub 2022 Apr 1.

Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania.

Reactive oxygen species (ROS)-mediated reductions in nitric oxide (NO)-dependent dilation are evident in adults with major depressive disorder (MDD); however, the upstream mechanisms remain unclear. Here, we hypothesized that nuclear factor-κB (NF-κB) activation-induced ROS production contributes to microvascular endothelial dysfunction in MDD. Thirteen treatment-naive adults with MDD (6 women; 19-23 yr) and 10 healthy nondepressed adults (HAs; 5 women; 20-25 yr) were tested before and after (open-label design) systemic NF-κB knockdown (nonacetylated salicylate; 3,000-4,500 mg/day × 4 days). Read More

View Article and Full-Text PDF

Mechanisms and clinical implications of endothelium-dependent vasomotor dysfunction in coronary microvasculature.

Am J Physiol Heart Circ Physiol 2022 May 25;322(5):H819-H841. Epub 2022 Mar 25.

Cardiovascular Research Center, Rhode Island Hospital, Providence, Rhode Island.

Coronary microvascular disease (CMD), which affects the arterioles and capillary endothelium that regulate myocardial perfusion, is an increasingly recognized source of morbidity and mortality, particularly in the setting of metabolic syndrome. The coronary endothelium plays a pivotal role in maintaining homeostasis, though factors such as diabetes, hypertension, hyperlipidemia, and obesity can contribute to endothelial injury and consequently arteriolar vasomotor dysfunction. These disturbances in the coronary microvasculature clinically manifest as diminished coronary flow reserve, which is a known independent risk factor for cardiac death, even in the absence of macrovascular atherosclerotic disease. Read More

View Article and Full-Text PDF

Assessments of microvascular function in organ systems.

Am J Physiol Heart Circ Physiol 2022 Jun 25;322(6):H891-H905. Epub 2022 Mar 25.

Cardiovascular Research Center, Rhode Island Hospital, Providence, Rhode Island.

Microvascular disease plays critical roles in the dysfunction of all organ systems, and there are many methods available to assess the microvasculature. These methods can either assess the target organ directly or assess an easily accessible organ such as the skin or retina so that inferences can be extrapolated to the other systems and/or related diseases. Despite the abundance of exploratory research on some of these modalities and their possible applications, there is a general lack of clinical use. Read More

View Article and Full-Text PDF

Loss of talin in cardiac fibroblasts results in augmented ventricular cardiomyocyte hypertrophy in response to pressure overload.

Am J Physiol Heart Circ Physiol 2022 May 25;322(5):H857-H866. Epub 2022 Mar 25.

Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee.

Pressure overload of the heart is characterized by concentric hypertrophy and interstitial fibrosis. Cardiac fibroblasts (CFs) in the ventricular wall become activated during injury and synthesize and compact the extracellular matrix, which causes interstitial fibrosis and stiffening of the ventricular heart walls. Talin1 (Tln1) and Talin2 (Tln2) are mechanosensitive proteins that participate in focal adhesion transmission of signals from the extracellular environment to the actin cytoskeleton of CFs. Read More

View Article and Full-Text PDF

Metabolic transformation of fat in obesity determines the inflammation resolving capacity of splenocardiac and cardiorenal networks in heart failure.

Am J Physiol Heart Circ Physiol 2022 Jun 25;322(6):H953-H970. Epub 2022 Mar 25.

Department of Cellular and Integrative Physiology, Center for Heart and Vascular Research, University of Nebraska Medical Center, Omaha, Nebraska.

All fats are not created equal, and despite the extensive literature, the effect of fat intake is the most debated question in obesity, cardiovascular, and cardiorenal research. Cellular and molecular mechanisms underlying cardiac dysfunction and consequent heart failure in the setting of obesity are not well understood. Our understanding of how fats are metabolically transformed after nonreperfused myocardial infarction (MI), in particular, is incomplete. Read More

View Article and Full-Text PDF

Matrix anisotropy promotes angiogenesis in a density-dependent manner.

Am J Physiol Heart Circ Physiol 2022 May 25;322(5):H806-H818. Epub 2022 Mar 25.

Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah.

Angiogenesis is necessary for wound healing, tumorigenesis, implant inosculation, and homeostasis. In each situation, matrix structure and mechanics play a role in determining whether new vasculatures can establish transport to new or hypoxic tissues. Neovessel growth and directional guidance are sensitive to three-dimensional (3-D) matrix anisotropy and density, although the individual and integrated roles of these matrix features have not been fully recapitulated in vitro. Read More

View Article and Full-Text PDF

Global Reach 2018: sympathetic neural and hemodynamic responses to submaximal exercise in Andeans with and without chronic mountain sickness.

Am J Physiol Heart Circ Physiol 2022 May 25;322(5):H844-H856. Epub 2022 Mar 25.

Department of Applied Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas.

Andeans with chronic mountain sickness (CMS) and polycythemia have similar maximal oxygen uptakes to healthy Andeans. Therefore, this study aimed to explore potential adaptations in convective oxygen transport, with a specific focus on sympathetically mediated vasoconstriction of nonactive skeletal muscle. In Andeans with (CMS, = 7) and without (CMS, = 9) CMS, we measured components of convective oxygen delivery, hemodynamic (arterial blood pressure via intra-arterial catheter), and autonomic responses [muscle sympathetic nerve activity (MSNA)] at rest and during steady-state submaximal cycling exercise [30% and 60% peak power output (PPO) for 5 min each]. Read More

View Article and Full-Text PDF

Microvascular dysfunction and neurovascular uncoupling are exacerbated in peripheral artery disease, increasing the risk of cognitive decline in older adults.

Am J Physiol Heart Circ Physiol 2022 Jun 25;322(6):H924-H935. Epub 2022 Mar 25.

Vascular Cognitive Impairment and Neurodegeneration Program, Oklahoma Center for Geroscience and Healthy Brain Aging, Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.

Peripheral artery disease (PAD) is a vascular pathology with high prevalence among the aging population. PAD is associated with decreased cognitive performance, but the underlying mechanisms remain obscure. Normal brain function critically depends on an adequate adjustment of cerebral blood supply to match the needs of active brain regions via neurovascular coupling (NVC). Read More

View Article and Full-Text PDF

Impact of ischemia on left atrial remodeling and dysfunction in swine models of mitral regurgitation.

Am J Physiol Heart Circ Physiol 2022 Jun 25;322(6):H914-H923. Epub 2022 Mar 25.

Cardiovascular Research Institute, Icahn School of Medicine at Mount Sinai, New York, New York.

Left atrial (LA) dysfunction is one of the predictive factors of worse outcomes after mitral valve surgery for mitral regurgitation (MR). We aimed to investigate the effect of MR etiology on progression of LA remodeling in swine MR models. MR was induced in 14 Yorkshire pigs using catheter-based procedures. Read More

View Article and Full-Text PDF