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.

Parental vitamin D deficiency during pregnancy is associated with increased blood pressure in offspring via Panx1 hypermethylation
Vitamin D deficiency is one of the most common nutritional deficiencies worldwide. Maternal vitamin D deficiency is associated with increased susceptibility to hypertension in offspring, but the reasons for this remain unknown. The aim of this study was to determine if parental vitamin D deficiency leads to altered DNA methylation in offspring that may relate to hypertension. Male and female Sprague-Dawley rats were fed a standard or vitamin D-depleted diet. After 10 wk, nonsibling rats were mated. The conceived pups received standard chow. We observed an increased systolic and diastolic blood pressure in the offspring fro...
Source: AJP: Heart and Circulatory Physiology - December 1, 2016 Category: Cardiology Authors: Meems, L. M. G., Mahmud, H., Buikema, H., Tost, J., Michel, S., Takens, J., Verkaik-Schakel, R. N., Vreeswijk-Baudoin, I., Mateo-Leach, I. V., van der Harst, P., Plösch, T., de Boer, R. A. Tags: CALL FOR PAPERS Source Type: research

H2S concentrations in the heart after acute H2S administration: methodological and physiological considerations
In this study, we have tried to characterize the limits of the approach typically used to determine H2S concentrations in the heart based on the amount of H2S evaporating from heart homogenates—spontaneously, after reaction with a strong reducing agent, or in a very acidic solution. Heart homogenates were prepared from male rats in control conditions or after H2S infusion induced a transient cardiogenic shock (CS) or cardiac asystole (CA). Using a method of determination of gaseous H2S with a detection limit of 0.2 nmol, we found that the process of homogenization could lead to a total disappearance of free H2S unles...
Source: AJP: Heart and Circulatory Physiology - December 1, 2016 Category: Cardiology Authors: Sonobe, T., Haouzi, P. Tags: CALL FOR PAPERS Source Type: research

Hydrogen sulfide-induced vasodilation mediated by endothelial TRPV4 channels
Hydrogen sulfide (H2S) is a recently described gaseous vasodilator produced within the vasculature by the enzymes cystathionine -lyase and 3-mercaptopyruvate sulfurtransferase. Previous data demonstrate that endothelial cells (EC) are the source of endogenous H2S production and are required for H2S-induced dilation. However, the signal transduction pathway activated by H2S within EC has not been elucidated. TRPV4 and large-conductance Ca2+-activated K channels (BK channels) are expressed in EC. H2S-induced dilation is inhibited by luminal administration of iberiotoxin and disruption of the endothelium. Calcium influx throu...
Source: AJP: Heart and Circulatory Physiology - December 1, 2016 Category: Cardiology Authors: Naik, J. S., Osmond, J. M., Walker, B. R., Kanagy, N. L. Tags: CALL FOR PAPERS Source Type: research

Ebselen does not improve oxidative stress and vascular function in patients with diabetes: a randomized, crossover trial
Oxidative stress is a key driver of vascular dysfunction in diabetes mellitus. Ebselen is a glutathione peroxidase mimetic. A single-site, randomized, double-masked, placebo-controlled, crossover trial was carried out in 26 patients with type 1 or type 2 diabetes to evaluate effects of high-dose ebselen (150 mg po twice daily) administration on oxidative stress and endothelium-dependent vasodilation. Treatment periods were in random order of 4 wk duration, with a 4-wk washout between treatments. Measures of oxidative stress included nitrotyrosine, plasma 8-isoprostanes, and the ratio of reduced to oxidized glutathione. Vas...
Source: AJP: Heart and Circulatory Physiology - November 30, 2016 Category: Cardiology Authors: Beckman, J. A., Goldfine, A. B., Leopold, J. A., Creager, M. A. Tags: VASCULAR BIOLOGY AND MICROCIRCULATION Source Type: research

Ion channel mechanisms of rat tail artery contraction-relaxation by menthol involving, respectively, TRPM8 activation and L-type Ca2+ channel inhibition
Transient receptor potential melastatin 8 (TRPM8) is the principal cold and menthol receptor channel. Characterized primarily for its cold-sensing role in sensory neurons, it is expressed and functional in several nonneuronal tissues, including vasculature. We previously demonstrated that menthol causes variable mechanical responses (vasoconstriction, vasodilatation, or biphasic reactions) in isolated arteries, depending on vascular tone. Here we aimed to dissect the specific ion channel mechanisms and corresponding Ca2+ signaling pathways underlying such complex responses to menthol and other TRPM8 ligands in rat tail art...
Source: AJP: Heart and Circulatory Physiology - November 30, 2016 Category: Cardiology Authors: Melanaphy, D., Johnson, C. D., Kustov, M. V., Watson, C. A., Borysova, L., Burdyga, T. V., Zholos, A. V. Tags: VASCULAR BIOLOGY AND MICROCIRCULATION Source Type: research

Association of CYP2C19 variants and epoxyeicosatrienoic acids on patients with microvascular angina
We examined the association of CYP2C19 polymorphisms and EETs on microvascular angina (MVA) caused by coronary microvascular dysfunction. We examined CYP2C19 genotypes in patients with MVA (n = 71) and healthy subjects as control (n = 71). MVA was defined as the absence of coronary artery stenosis and epicardial spasms and the presence of inversion of lactic acid levels between intracoronary and coronary sinuses in acetylcholine-provocation test or the adenosine-triphosphate-induced coronary flow reserve ratio was below 2.5. CYP2C19 PM have two loss-of-functon alleles (*2, *3). We measured serum dihydroxyeicosatrienoic aci...
Source: AJP: Heart and Circulatory Physiology - November 30, 2016 Category: Cardiology Authors: Akasaka, T., Sueta, D., Arima, Y., Tabata, N., Takashio, S., Izumiya, Y., Yamamoto, E., Yamamuro, M., Tsujita, K., Kojima, S., Kaikita, K., Kajiwara, A., Morita, K., Oniki, K., Saruwatari, J., Nakagawa, K., Ogata, Y., Matsui, K., Hokimoto, S. Tags: VASCULAR BIOLOGY AND MICROCIRCULATION Source Type: research

Carboxy-terminal deletion of the HDL receptor reduces receptor levels in liver and steroidogenic tissues, induces hypercholesterolemia, and causes fatal heart disease
The HDL receptor SR-BI mediates the transfer of cholesteryl esters from HDL to cells and controls HDL abundance and structure. Depending on the genetic background, loss of SR-BI causes hypercholesterolemia, anemia, reticulocytosis, splenomegaly, thrombocytopenia, female infertility, and fatal coronary heart disease (CHD). The carboxy terminus of SR-BI (505QEAKL509) must bind to the cytoplasmic adaptor PDZK1 for normal hepatic—but not steroidogenic cell—expression of SR-BI protein. To determine whether SR-BI's carboxy terminus is also required for normal protein levels in steroidogenic cells, we introduced into ...
Source: AJP: Heart and Circulatory Physiology - November 30, 2016 Category: Cardiology Authors: Pal, R., Ke, Q., Pihan, G. A., Yesilaltay, A., Penman, M. L., Wang, L., Chitraju, C., Kang, P. M., Krieger, M., Kocher, O. Tags: SIGNALING AND STRESS RESPONSE Source Type: research

Influence of menopause status and age on integrated central and peripheral hemodynamic responses to subsystolic cuffing during submaximal exercise
Although pathophysiological links between postmenopause and healthy aging remain unclear, both factors are associated with increased blood pressure and sympathetic nerve activity (SNA) in women. Activation of polymodal musculoskeletal neural afferents originating within adventia of venules modulates SNA and blood pressure control during exercise in healthy adults. We hypothesized transient subsystolic regional circulatory occlusion (RCO) during exercise sensitizes these afferents leading to augmented systemic vascular resistance (SVR)-mediated increased mean arterial pressure (MAP) in postmenopause vs. premenopause. Normot...
Source: AJP: Heart and Circulatory Physiology - November 30, 2016 Category: Cardiology Authors: Van Iterson, E. H., Gramm, C., Randall, N. R., Olson, T. P. Tags: INTEGRATIVE CARDIOVASCULAR PHYSIOLOGY AND PATHOPHYSIOLOGY Source Type: research

Exercise-induced brachial artery blood flow and vascular function is impaired in systemic sclerosis
Systemic sclerosis (SSc) is a rare autoimmune disease characterized by debilitating fibrosis and vascular dysfunction; however, little is known about the circulatory response to exercise in this population. Therefore, we examined the peripheral hemodynamic and vasodilatory responses to handgrip exercise in 10 patients with SSc (61 ± 4 yr) and 15 age-matched healthy controls (56 ± 5 yr). Brachial artery diameter, blood flow, and mean arterial pressure (MAP) were determined at rest and during progressive static-intermittent handgrip exercise. Patients with SSc and controls were similar in body stature, handgrip...
Source: AJP: Heart and Circulatory Physiology - November 30, 2016 Category: Cardiology Authors: Machin, D. R., Clifton, H. L., Garten, R. S., Gifford, J. R., Richardson, R. S., Wray, D. W., Frech, T. M., Donato, A. J. Tags: INTEGRATIVE CARDIOVASCULAR PHYSIOLOGY AND PATHOPHYSIOLOGY Source Type: research

Heart-lung interaction in a model of COPD: importance of lung volume and direct ventricular interaction
Chronic obstructive pulmonary disease (COPD) is associated with dynamic lung hyperinflation (DH), increased pulmonary vascular resistance (PVR), and large increases in negative intrathoracic pressure (nITP). The individual and interactive effect of these stressors on left ventricular (LV) filling, emptying, and geometry and the role of direct ventricular interaction (DVI) in mediating these interactions have not been fully elucidated. Twenty healthy subjects were exposed to the following stressors alone and in combination: 1) inspiratory resistive loading of –20 cmH2O (nITP), 2) expiratory resistive loading to cause ...
Source: AJP: Heart and Circulatory Physiology - November 30, 2016 Category: Cardiology Authors: Cheyne, W. S., Williams, A. M., Harper, M. I., Eves, N. D. Tags: INTEGRATIVE CARDIOVASCULAR PHYSIOLOGY AND PATHOPHYSIOLOGY Source Type: research

Effects of various types of anesthesia on hemodynamics, cardiac function, and glucose and lipid metabolism in rats
Anesthesia can affect respiratory, circulatory, and endocrine systems but is necessary for certain experimental procedures such as echocardiography and blood sampling in small animals. We have now investigated the effects of four types of anesthesia [pentobarbital sodium (PENT), ketamine-xylazine (K/X), and low- or high-dose isoflurane (ISO)] on hemodynamics, cardiac function, and glucose and lipid metabolism in Sprague-Dawley rats. Aortic pressure, heart rate, and echocardiographic parameters were measured at various time points up to 45 min after the induction of anesthesia, and blood was then collected for measurement o...
Source: AJP: Heart and Circulatory Physiology - November 30, 2016 Category: Cardiology Authors: Sano, Y., Ito, S., Yoneda, M., Nagasawa, K., Matsuura, N., Yamada, Y., Uchinaka, A., Bando, Y. K., Murohara, T., Nagata, K. Tags: CARDIOVASCULAR NEUROHORMONAL REGULATION Source Type: research

Dyssynchronous calcium removal in heart failure-induced atrial remodeling
We tested the hypothesis that in atrial myocytes from a rabbit left ventricular heart failure (HF) model, spatial inhomogeneity and temporal dyssynchrony of Ca removal during excitation-contraction coupling together with increased Na/Ca exchange (NCX) activity generate a substrate for proarrhythmic Ca release. Ca removal occurs via Ca reuptake into the sarcoplasmic reticulum and extrusion via NCX exclusively in the cell periphery since rabbit atrial myocytes lack transverse tubules. Ca removal kinetics were assessed by the time constant of decay of local peripheral subsarcolemmal (SS) and central (CT) action potential (AP)...
Source: AJP: Heart and Circulatory Physiology - November 30, 2016 Category: Cardiology Authors: Hohendanner, F., DeSantiago, J., Heinzel, F. R., Blatter, L. A. Tags: CARDIAC EXCITATION AND CONTRACTION Source Type: research

Coronary microvascular dysfunction after long-term diabetes and hypercholesterolemia
In conclusion, 15 mo of DM + HFD, as well as HFD alone, resulted in CMD. Although the overall vasodilation to BK was unperturbed, the relative contributions of NO and endothelium-derived hyperpolarizing factor pathways were altered. Moreover, the vasoconstrictor response to ET-1 was enhanced, involving the ETB receptors. In conjunction with our previous study, these findings highlight the time dependence of the phenotype of CMD. (Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - November 30, 2016 Category: Cardiology Authors: Sorop, O., van den Heuvel, M., van Ditzhuijzen, N. S., de Beer, V. J., Heinonen, I., van Duin, R. W. B., Zhou, Z., Koopmans, S. J., Merkus, D., van der Giessen, W. J., Danser, A. H. J., Duncker, D. J. Tags: CALL FOR PAPERS Source Type: research

Reply to "Letter to the editor: Why persist in the fallacy that mean systemic pressure drives venous return?"
(Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - October 31, 2016 Category: Cardiology Authors: Berger, D., Moller, P. W., Takala, J. Tags: Editorials and Letters to the Editor LETTER TO THE EDITOR Source Type: research

Letter to the editor: Why persist in the fallacy that mean systemic pressure drives venous return?
(Source: AJP: Heart and Circulatory Physiology)
Source: AJP: Heart and Circulatory Physiology - October 31, 2016 Category: Cardiology Authors: Brengelmann, G. L. Tags: Editorials and Letters to the Editor LETTER TO THE EDITOR Source Type: research