AJP: Heart and Circulatory Physiology This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

A novel method of standardized myocardial infarction in aged rabbits
This study describes the coronary angiographic imaging of young and aged rabbits. We developed and improved a novel minimally invasive approach for coil embolization that targets a specific area of myocardium and yielded a consistent scar encompassing ~30% of the left ventricular free wall of young and aged rabbit hearts. (Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - May 1, 2017 Category: Cardiology Authors: Morrissey, P. J., Murphy, K. R., Daley, J. M., Schofield, L., Turan, N. N., Arunachalam, K., Abbott, J. D., Koren, G. Tags: INNOVATIVE METHODOLOGY Source Type: research

Smooth muscle cell-specific deletion of Col15a1 unexpectedly leads to impaired development of advanced atherosclerotic lesions
We report the first direct in vivo evidence that a smooth muscle cell (SMC)-produced collagen, collagen type XV (COL15A1), is critical for atherosclerotic lesion development. SMC Col15a1 knockout markedly attenuated advanced lesion formation, likely through reducing SMC proliferation and impairing multiple proatherogenic inflammatory processes. (Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - May 1, 2017 Category: Cardiology Authors: Durgin, B. G., Cherepanova, O. A., Gomez, D., Karaoli, T., Alencar, G. F., Butcher, J. T., Zhou, Y.-Q., Bendeck, M. P., Isakson, B. E., Owens, G. K., Connelly, J. J. Tags: RESEARCH ARTICLE Source Type: research

Noninvasive stratification of postinfarction rats based on the degree of cardiac dysfunction using magnetic resonance imaging and echocardiography
The myocardial infarction (MI) rat model plays a crucial role in modern cardiovascular research, but the inherent heterogeneity of this model represents a challenge. We sought to identify subgroups among the post-MI rats and establish simple noninvasive stratification protocols for such subgroups. Six weeks after induction of MI, 49 rats underwent noninvasive examinations using magnetic resonance imaging (MRI) and echocardiography. Twelve sham-operated rats served as controls. Increased end-diastolic left ventricular (LV) pressure and lung weight served as indicators for congestive heart failure (CHF). A clustering algorit...
Source: AJP: Heart and Circulatory Physiology - May 1, 2017 Category: Cardiology Authors: Aronsen, J. M., Espe, E. K. S., Skardal, K., Hasic, A., Zhang, L., Sjaastad, I. Tags: RESEARCH ARTICLE Source Type: research

Effects of {beta}-adrenergic receptor drugs on embryonic ventricular cell proliferation and differentiation and their impact on donor cell transplantation
β-Adrenergic receptors (β-ARs) and catecholamines are present in rodents as early as embryonic day (E)10.5. However, it is not known whether β-AR signaling plays any role in the proliferation and differentiation of ventricular cells in the embryonic heart. Here, we characterized expression profiles of β-AR subtypes and established dose-response curves for the nonselective β-AR agonist isoproterenol (ISO) in the developing mouse ventricular cells. Furthermore, we investigated the effects of ISO on cell cycle activity and differentiation of cultured E11.5 ventricular cells. ISO treatment significantl...
Source: AJP: Heart and Circulatory Physiology - May 1, 2017 Category: Cardiology Authors: Feridooni, T., Hotchkiss, A., Baguma-Nibasheka, M., Zhang, F., Allen, B., Chinni, S., Pasumarthi, K. B. S. Tags: RESEARCH ARTICLE Source Type: research

ERBB signaling attenuates proinflammatory activation of nonclassical monocytes
This study identified a novel role of neuregulin-1 (NRG-1)/ERBB signaling in the control of proinflammatory activation of monocytes. These results further improve our fundamental understanding of cardioprotective effects of NRG-1 in patients with heart failure. (Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - May 1, 2017 Category: Cardiology Authors: Ryzhov, S., Matafonov, A., Galindo, C. L., Zhang, Q., Tran, T.-L., Lenihan, D. J., Lenneman, C. G., Feoktistov, I., Sawyer, D. B. Tags: RESEARCH ARTICLE Source Type: research

Short-term regular aerobic exercise reduces oxidative stress produced by acute in the adipose microvasculature
In conclusion, aerobic exercise prevents high pressure-induced vascular dysfunction through an improved redox environment in the adipose microvasculature. NEW & NOTEWORTHY We describe potential mechanisms contributing to aerobic exercise-conferred protection against high intravascular pressure. Subcutaneous adipose microvessels from exercise mice express less NADPH oxidase (NOX) II and more superoxide dismutase (SOD) and demonstrate less sensitivity to ANG II. In microvascular endothelial cells, shear stress reduced NOX II but did not influence SOD expression. (Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - May 1, 2017 Category: Cardiology Authors: Robinson, A. T., Fancher, I. S., Sudhahar, V., Bian, J. T., Cook, M. D., Mahmoud, A. M., Ali, M. M., Ushio-Fukai, M., Brown, M. D., Fukai, T., Phillips, S. A. Tags: RESEARCH ARTICLE Source Type: research

Mild hypothermia preserves myocardial conduction during ischemia by maintaining gap junction intracellular communication and Na+ channel function
In conclusion, MH preserves myocardial conduction during prolonged ischemia by maintaining Cx43 expression at the ID and maintaining NaCh function. Hypothermic preservation of GJ coupling and NaCh may be novel antiarrhythmic strategies during resuscitation. NEW & NOTEWORTHY Therapeutic hypothermia is now a class I recommendation for resuscitation from cardiac arrest. This study determined that hypothermia preserves gap junction coupling as well as Na+ channel function during acute cardiac ischemia, attenuating conduction slowing and preventing conduction block, suggesting that induced hypothermia may be a novel antiarr...
Source: AJP: Heart and Circulatory Physiology - May 1, 2017 Category: Cardiology Authors: Nassal, M. M. J., Wan, X., Dale, Z., Deschenes, I., Wilson, L. D., Piktel, J. S. Tags: RESEARCH ARTICLE Source Type: research

Hydrogen sulfide alleviates hypertensive kidney dysfunction through an epigenetic mechanism
In this study, we sought to identify whether microRNAs are dysregulated in response to angiotensin II (ANG II)-induced hypertension in the kidney and whether a H2S donor, GYY4137, could reverse the microRNA alteration and kidney function. Wild-type (C57BL/6J) mice were treated without or with ANG II and GYY4137 for 4 wk. Blood pressure, renal blood flow, and resistive index (RI) were measured. MicroRNA microarrays were conducted and subsequent target prediction revealed genes associated with a proinflammatory response. ANG II treatment significantly increased blood pressure, decreased blood flow in the renal cortex, increa...
Source: AJP: Heart and Circulatory Physiology - May 1, 2017 Category: Cardiology Authors: Weber, G. J., Pushpakumar, S. B., Sen, U. Tags: RESEARCH ARTICLE Source Type: research

Psoriasis as a human model of disease to study inflammatory atherogenesis
Inflammation is known to play a significant role in the process of atherogenesis and cardiovascular disease (CVD). Indeed, patients with chronic inflammatory diseases are at increased risk for cardiovascular events. However, the mechanisms linking chronic inflammation and CVD remain poorly understood. Psoriasis, a chronic inflammatory skin disease associated with a greater risk of early cardiovascular events, provides a suitable human model to study the pathophysiology of inflammatory atherogenesis in humans. Additionally, cytokines such as TNF-α, IL-17A, and other immune pathways are the common links between the pat...
Source: AJP: Heart and Circulatory Physiology - May 1, 2017 Category: Cardiology Authors: Harrington, C. L., Dey, A. K., Yunus, R., Joshi, A. A., Mehta, N. N. Tags: REVIEW Source Type: research

Can endothelial hemoglobin-{alpha} regulate nitric oxide vasodilatory signaling?
We used mathematical modeling to investigate nitric oxide (NO)-dependent vasodilatory signaling in the arteriolar wall. Detailed continuum cellular models of calcium (Ca2+) dynamics and membrane electrophysiology in smooth muscle and endothelial cells (EC) were coupled with models of NO signaling and biotransport in an arteriole. We used this theoretical approach to examine the role of endothelial hemoglobin-α (Hbα) as a modulator of NO-mediated myoendothelial feedback, as previously suggested in Straub et al. (Nature 491: 473–477, 2012). The model considers enriched expression of inositol 1,4,5-triphosph...
Source: AJP: Heart and Circulatory Physiology - April 7, 2017 Category: Cardiology Authors: Parikh, J., Kapela, A., Tsoukias, N. M. Tags: RESEARCH ARTICLE Source Type: research

Resveratrol improves exercise performance and skeletal muscle oxidative capacity in heart failure
We investigated whether treatment of mice with established pressure overload-induced heart failure (HF) with the naturally occurring polyphenol resveratrol could improve functional symptoms of clinical HF such as fatigue and exercise intolerance. C57Bl/6N mice were subjected to either sham or transverse aortic constriction surgery to induce HF. Three weeks postsurgery, a cohort of mice with established HF (%ejection fraction <45) was administered resveratrol (~450 mg·kg–1·day–1) or vehicle for 2 wk. Although the percent ejection fraction was similar between both groups of HF mice, those mice tr...
Source: AJP: Heart and Circulatory Physiology - April 7, 2017 Category: Cardiology Authors: Sung, M. M., Byrne, N. J., Robertson, I. M., Kim, T. T., Samokhvalov, V., Levasseur, J., Soltys, C.-L., Fung, D., Tyreman, N., Denou, E., Jones, K. E., Seubert, J. M., Schertzer, J. D., Dyck, J. R. B. Tags: RESEARCH ARTICLE Source Type: research

Impaired peripheral vasodilation during graded systemic hypoxia in healthy older adults: role of the sympathoadrenal system
Systemic hypoxia is a physiological and pathophysiological stress that activates the sympathoadrenal system and, in young adults, leads to peripheral vasodilation. We tested the hypothesis that peripheral vasodilation to graded systemic hypoxia is impaired in older healthy adults and that this age-associated impairment is due to attenuated β-adrenergic mediated vasodilation and elevated α-adrenergic vasoconstriction. Forearm blood flow was measured (Doppler ultrasound), and vascular conductance (FVC) was calculated in 12 young (24 ± 1 yr) and 10 older (63 ± 2 yr) adults to determine the local dilat...
Source: AJP: Heart and Circulatory Physiology - April 7, 2017 Category: Cardiology Authors: Richards, J. C., Crecelius, A. R., Larson, D. G., Luckasen, G. J., Dinenno, F. A. Tags: RESEARCH ARTICLE Source Type: research

Transcranial Doppler-determined change in posterior cerebral artery blood flow velocity does not reflect vertebral artery blood flow during exercise
We examined whether a change in posterior cerebral artery flow velocity (PCAv) reflected the posterior cerebral blood flow in healthy subjects during both static and dynamic exercise. PCAv and vertebral artery (VA) blood flow, as an index of posterior cerebral blood flow, were continuously measured during an exercise trial using transcranial Doppler (TCD) ultrasonography and Doppler ultrasound, respectively. Static handgrip exercise significantly increased both PCAv and VA blood flow. Increasing intensity of dynamic exercise further increased VA blood flow from moderate exercise, while PCAv decreased to almost resting leve...
Source: AJP: Heart and Circulatory Physiology - April 7, 2017 Category: Cardiology Authors: Washio, T., Sasaki, H., Ogoh, S. Tags: RESEARCH ARTICLE Source Type: research

Exosomes from pediatric dilated cardiomyopathy patients modulate a pathological response in cardiomyocytes
Stimulation of the renin-angiotensin-aldosterone system (RAAS) and β-adrenergic receptors plays an important role in adult heart failure (HF). Despite the demonstrated benefits of RAAS inhibition and β-adrenergic receptor blockade in adult HF patients, no substantial improvement in survival rate has been observed in children with HF. This suggests that the underlying disease mechanism is uniquely regulated in pediatric HF. Here, we show that treatment of human-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) and neonatal rat ventricular myocytes (NRVMs) with serum from pediatric dilated cardiomyopa...
Source: AJP: Heart and Circulatory Physiology - April 7, 2017 Category: Cardiology Authors: Jiang, X., Sucharov, J., Stauffer, B. L., Miyamoto, S. D., Sucharov, C. C. Tags: RESEARCH ARTICLE Source Type: research

Optogenetic identification of hypothalamic orexin neuron projections to paraventricular spinally projecting neurons
Orexin neurons, and activation of orexin receptors, are generally thought to be sympathoexcitatory; however, the functional connectivity between orexin neurons and a likely sympathetic target, the hypothalamic spinally projecting neurons (SPNs) in the paraventricular nucleus of the hypothalamus (PVN) has not been established. To test the hypothesis that orexin neurons project directly to SPNs in the PVN, channelrhodopsin-2 (ChR2) was selectively expressed in orexin neurons to enable photoactivation of ChR2-expressing fibers while examining evoked postsynaptic currents in SPNs in rat hypothalamic slices. Selective photoacti...
Source: AJP: Heart and Circulatory Physiology - April 7, 2017 Category: Cardiology Authors: Dergacheva, O., Yamanaka, A., Schwartz, A. R., Polotsky, V. Y., Mendelowitz, D. Tags: RESEARCH ARTICLE Source Type: research