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The present study was undertaken to address the concern that author compliance with American Physiological Society (APS) journal instructions to authors for data presentation in manuscript figures is inadequate. Common instances of noncompliance are omitted molecular weight markers for immunoblots and bar graphs lacking individual data points. The American Journal of Physiology-Heart and Circulatory Physiology ( AJP-Heart and Circ ) editorial team designed a program to assess figure data presentation in submitted manuscripts. The intended outcome was to improve author compliance with APS data presentation guidelines and to improve overall rigor and reproducibility in articles published in AJP-Heart and Circ . The AJP-Heart and Circ team invited 37 peer reviewers to participate in a figure reviewer project (FRp). Over a period of five months, 32 first-revision manuscripts were enrolled in the FRp. Each manuscript was reviewed by the original peer reviewers and an additional figure reviewer (FR). Post-peer review, corresponding authors and FRs were surveyed for insight into their experiences. Of the 32 corresponding authors invited, 20 (63%) responded to the survey. In response to the survey, 100% of respondents stated that peer review was performed in a timely fashion despite the additional FR. When asked whether the FR experience had any effect on how one would present data in manuscript figures in future submissions, 65% of authors and 83% of FRs said yes. In addition, 63% of authors responding agreed that the overall quality of their figures was improved after revising based on FR comments. This exercise resulted in improved compliance with APS data presentation guidelines and changed attitudes among both authors and reviewers as to the need for consistent and clear data presentation in manuscript figures. NEW & NOTEWORTHY The goal of the American Journal of Physiology-Heart and Circulatory Physiology figure reviewer program was to improve author compliance with existing APS data presentation instructions for manuscript figures. The result was an improvement in compliance with these guidelines. Time from submission to final decision did not significantly increase for papers with the additional figure reviewer, and both figure reviewers and corresponding authors reported positive feedback in post-program surveys.

Underserved minority groups are disproportionately absent from the pursuit of careers in science, technology, engineering, and mathematics (STEM) fields. One such underserved population, Native Americans, are particularly underrepresented in STEM fields. Although recent advocacy and outreach designed toward increasing minority involvement in health care-related occupations have been mostly successful, little is known about the efficacy of outreach programs in increasing minority enthusiasm toward careers in traditional scientific professions. Furthermore, very little is known about outreach among Native American schools toward increasing involvement in STEM. We collaborated with tribal middle and high schools in South Dakota and Nebraska through a National Institutes of Health Science Education Partnership Award to hold a day-long physiology, activity-based event to increase both understanding of physiology and enthusiasm to scientific careers. We recruited volunteer biomedical scientists and trainees from the University of Nebraska Medical Center, Nebraska Wesleyan University, and University of South Dakota. To evaluate the effectiveness of the day of activities, 224 of the ~275-300 participating students completed both a pre- and postevent evaluation assessment. We observed increases in both students self-perceived knowledge of physiology and enthusiasm toward scientific career opportunities after the day of outreach activities. We conclude that activity-based learning opportunities in underserved populations are effective in increasing both knowledge of science and interest in scientific careers., (Copyright © 2017 the American Physiological Society.)

Exercise training has been shown to ameliorate a wide variety of cardiovascular disorders. The mechanisms by which long-term benefits of exercise training are mediated remains incomplete, despite intense research in this area. Exactly how the act of chronic exercise improves function in every tissue is unknown, but many of the cellular, molecular, and genetic mechanisms are becoming progressively clearer. This "Perspectives" article reviews the contributions of 15 articles published in the American Journal of Physiology-Heart and Circulatory Physiology in response to a Call for Papers in this area. Here, we summarize the contributions of these studies at the cardiac, vascular, immune, and molecular levels. We discuss the translational benefit of these studies and conclude that the beneficial effects of exercise training in cardiovascular disease is due to a large interplay of cellular and molecular mediators in the heart and peripheral vasculature as well as changes in neural elements that regulate blood pressure and blood flow. Readers are encouraged to evaluate and learn from this collection of novel studies. [ABSTRACT FROM AUTHOR]

Several sympathoexcitatory reflexes, such as the cardiac sympathetic afferent reflex (CSAR) and arterial chemoreflex, are significantly augmented and contribute to elevated sympathetic outflow in chronic heart failure (CHF). This study was undertaken to investigate the interaction between the CSAR and the chemoreflex in CHF and to further identify the involvement of angiotensin II type I receptors (AT1Rs) in the nucleus of the tractus solitarius (NTS) in this interaction. CHF was induced in rats by coronary ligation. Acute experiments were performed in anesthetized rats. The chemoreflex-induced increase in cardiovascular responses was significantly greater in CHF than in sham-operated rats after either chemical or electrical activation of the CSAR. The inhibition of the CSAR by epicardial lidocaine reduced the chemoreflex-induced effects in CHF rats but not in sham-operated rats. Bilateral NTS injection of the AT1R antagonist losartan (10 and 100 pmol) dose-dependently decreased basal sympathetic nerve activity in CHF but not in sham-operated rats. This procedure also abolished the CSAR-induced enhancement of the chemoreflex. The discharge and chemo-sensitivity of NTS chemosensitive neurons were significantly increased following the stimulation of the CSAR in sham-operated and CHF rats, whereas CSAR inhibition by epicardial lidocaine significantly attenuated chemosensitivity of NTS neurons in CHF but not in sham-operated rats. Finally, the protein expression of AT1R in the NTS was significantly higher in CHF than in sham-operated rats. These results demonstrate that the enhanced cardiac sympathetic afferent input contributes to an excitatory effect of chemoreflex function in CHF, which is mediated by an NTS-AT1R-dependent mechanism. [ABSTRACT FROM AUTHOR]

Focuses on a study that examined the influence of overexpression of neuronal nitric oxide (NO) synthase within the paraventricular nucleus on renal sympatheric nerve discharge. Background on the role of NO in cardiovascular homeostasis; Methods used; Results and discussion.

Focuses on a study which investigated the effect of reduced nitric oxide (NO) on cardiac sympathetic afferent reflex (CSAR) in dogs with congestive heart failure (CHF). Role of cardiac sympathetic excitability in CHF; Experimentations; Inhibitory mechanism of NO on CSAR determined.

Investigates the effect of the neuronal nitric oxide (NO) synthase inhibitor 7-nitroindazole on the baroreflex control of heart rate (HR) and renal sympathetic nerve activity (RSNA) in the rabbit. Influence of blockade of neuronal NO synthase on baroreflex control of HR; Role of endogenous brain NO in decreasing the baroreflex control of HR.

Increased sympathetic nerve activity and the activation of the central renin-angiotensin system are commonly associated with cardiovascular disease states such as hypertension and heart failure, yet the precise mechanisms contributing to the long-term maintenance of this sympatho-excitation are incompletely understood. Due to the established physiological role of neurotrophins contributing toward neuroplasticity and neuronal excitability along with recent evidence linking the renin-angiotensin system and brain-derived neurotrophic factor (BDNF) along with its receptor (TrkB), it is likely the two systems interact to promote sympatho-excitation during cardiovascular disease. However, this interaction has not yet been fully demonstrated, in vivo. Thus, we hypothesized that central angiotensin II (Ang II) treatment will evoke a sympatho-excitatory state mediated through the actions of BDNF/TrkB. We infused Ang II (20 ng/min) into the right lateral ventricle of male Sprague-Dawley rats for twelve days with or without the TrkB receptor antagonist, ANA-12 (50 ng/h). We found that ICV infusion of Ang II increased mean arterial pressure (+ 40.4 mm Hg), increased renal sympathetic nerve activity (+ 19.4% max activity), and induced baroreflex dysfunction relative to vehicle. Co-infusion of ANA-12 attenuated the increase in blood pressure (− 20.6 mm Hg) and prevented the increase in renal sympathetic nerve activity (− 22.2% max) and baroreflex dysfunction relative to Ang II alone. Ang II increased thirst and decreased food consumption, and Ang II + ANA-12 augmented the thirst response while attenuating the decrease in food consumption. We conclude that TrkB signaling is a mediator of the long-term blood pressure and sympathetic nerve activity responses to central Ang II activity. These findings demonstrate the involvement of neurotrophins such as BDNF in promoting Ang II-induced autonomic dysfunction and further implicate TrkB signaling in modulating presympathetic autonomic neurons during cardiovascular disease. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to examine the effect of transthoracic ultrasound (TTU) and intravenous microbubbles (MB) on cardiac mechanoreceptors. In 16 rabbits (eight normal and eight chronic heart failure), renal sympathetic nerve activity (RSNA), heart rate and mean arterial pressure were examined before, during and after 1 MHz TTU at different peak negative pressures (0.12 to 0.43 MPa) and duty cycles in the presence and absence of perfluorocarbon MB. TTU applications were for 10 s, and the overall duration of MB infusion was approximately 60 s for each setting. TTU without MB had no effect on any parameter. During the microbubble infusion, however, TTU at higher peak negative pressures (≥0.27 MPa) and 100% duty cycle resulted in a consistent decrease in RSNA(–41 ± 41% p < 0.001). This was accompanied by brief reflex reductions in mean arterial pressure and heart rate. The changes in RSNA induced by TTU and MB in all rabbits were abolished by vagotomy. TTU, in the presence of MB, stimulates mechanoreceptors in the heart reflexively to reduce RSNA. (E-mail: trporter@unmc.edu) [Copyright &y& Elsevier]