A5006811250- Heart Rate Variability and Autonomic Control
- Cardiovascular and exercise physiology
- Thermoregulation and physiological responses
- Cardiac Health and Mental Health
- Neuroscience of respiration and sleep
- Cardiovascular, Neuropeptides, and Oxidative Stress Research
- Cardiovascular Syncope and Autonomic Disorders
- Cardiovascular Function and Risk Factors
- Cardiovascular Issues in Pregnancy
- Cardiovascular Health and Disease Prevention
- Sports Performance and Training
- Stress Responses and Cortisol
- Biochemical effects in animals
- Cardiovascular Disease and Adiposity
- Neonatal and fetal brain pathology
- Infrared Thermography in Medicine
- Pregnancy and preeclampsia studies
- Menopause: Health Impacts and Treatments
- Neuropeptides and Animal Physiology
- High Altitude and Hypoxia
- Birth, Development, and Health
- Traumatic Brain Injury and Neurovascular Disturbances
- Nitric Oxide and Endothelin Effects
- Intensive Care Unit Cognitive Disorders
- Anesthesia and Neurotoxicity Research
Texas Health Dallas
2020-2025
Institute for Exercise and Environmental Medicine
2020-2025
Presbyterian Hospital
2020-2025
The University of Texas Southwestern Medical Center
2021-2025
Western Sydney University
2015-2019
Background: We tested the hypothesis that patients with heart failure preserved ejection fraction (HFpEF) would have greater muscle sympathetic nerve activity (MSNA) at rest and reactivity during a cold pressor test compared non–heart controls. Further, given importance of baroreflex modulation MSNA in control blood pressure (BP), we hypothesized HFpEF exhibit reduced sensitivity. METHODS: Twenty-eight 44 matched controls (mean±SD: 71±8 versus 70±7 years; 9 men/19 women 16 men/28 women) were...
Abstract The impact of age on exercise pressor responses is equivocal, likely because sex‐specific neuro‐cardiovascular changes with age. However, assessments the interactive effects and sex muscle sympathetic nerve activity (MSNA) to are lacking. We tested hypothesis that older females would exhibit exaggerated increases in blood pressure (BP) MSNA discharge patterns during handgrip compared similarly aged males young adults. Twenty‐five (25 (2) years; mean (SD)) (YM; n = 12) (YF; 13) 23...
Low baroreflex sensitivity (BRS) is associated with elevated cardiovascular risk. However, the evidence based primarily on measurements of cardiac BRS. It cannot be assumed that or sympathetic BRS alone represent a true reflection control blood pressure. The aim this study was to examine relationship between spontaneous and in healthy, young individuals. Continuous pressure, heart rate, muscle nerve activity (MSNA) were made under resting conditions 50 healthy individuals (18-28 years)....
Research indicates that individuals may experience a rise (positive responders) or fall (negative in muscle sympathetic nerve activity (MSNA) during mental stress. In this study, we examined the early blood pressure responses (including peak, time of peak and rate pressure) to stress positive negative responders. Negative MSNA responders exhibit more rapid diastolic at onset stressor, suggesting baroreflex-mediated suppression MSNA. there is sluggish stress, which appears be MSNA-driven....
Sympathetic baroreflex sensitivity (BRS) is a measure of how effectively the buffers beat-to-beat changes in blood pressure through modulation muscle sympathetic nerve activity (MSNA). However, current methods assessment do not take into account transduction at level vasculature, which known to vary between individuals. In this study we tested hypothesis that there an inverse relationship BRS and vascular transduction. 38 (18 men) healthy adults, continuous measurements pressure, MSNA...
Sympathetic vascular transduction is attenuated in older compared with young adults, regardless of biological sex. Males, but not females (regardless age), demonstrate an inverse relationship between central (sympathetic baroreflex sensitivity) and peripheral transduction) components the arc. Young males exhibit resting sympathetic outflow transduction. Our results indicate that age sex exert independent interactive effects on neurohemodynamic balance humans.
While previous work has demonstrated that oral contraceptive pill (OCP) use does not affect resting muscle sympathetic nerve activity (MSNA), growing evidence indicates it attenuates neurogenic vasoconstriction. Despite these advances, remains unknown how OCP affects the ability of MSNA to dynamically control vascular tone and arterial blood pressure (BP) on a beat-by-beat basis. Thus, we tested hypothesis that, compared naturally menstruating females (MC), those using OCPs will exhibit...
Body posture and biological sex exhibit independent effects on the sympathetic neural responses to dynamic exercise. However, mechanisms (e.g., baroreflex) by which impacts outflow during rhythmic muscular contractions, whether affects posture-mediated changes in efferent nerve traffic exercise, remain unknown. Thus, we tested hypotheses that increases muscle activity (MSNA) would be greater upright compared with supine handgrip (RHG) females demonstrate smaller MSNA RHG exercise than males....
Abstract Metabolic inhibition of sympathetic vasoconstriction (functional sympatholysis) is essential for adequate perfusion skeletal muscle during exercise. Neuropeptide Y (NPY) a neurotransmitter that elicits potent and co‐released with noradrenaline sympathoexcitation. NPY released from nerves exercise; however, no study has assessed whether NPY‐mediated sensitive to metabolic in humans. We tested the hypothesis post‐junctional would be handgrip exercise similar degree as α 1 ‐adrenergic...
The ability of the arterial baroreflex to regulate blood pressure may influence magnitude morning surge in pressure. aim was investigate relationships between sympathetic and cardiac sensitivity (BRS) surge. Twenty-four hour ambulatory recorded 14 young individuals. defined via pre-awakening method, which is calculated as difference mean values two hours before after rising from sleep. systolic surge, diastolic pressures were 15 ± 2 mmHg, 13 1 mmHg 11 respectively. During laboratory...
While biological sex affects the neurocirculatory adjustments to exercise, effects of hormones on sympathetic action potential (AP) patterns and ensuing vascular transduction remain unknown. We tested hypothesis that males, females using oral contraceptive pills (OCPs), would demonstrate larger increases in activation compared with naturally menstruating during static handgrip exercise (SHG) postexercise circulatory occlusion (PECO). Young males [n = 14, 25 (5) yr], OCPs 16, 24 (6) 18, 26...
We have previously shown in young males that the rate of rise blood pressure (BP) at onset mental stress determines whether or not muscle sympathetic nerve activity (MSNA) has a role driving pressor response. The aim this study was to investigate these interactions females. BP and MSNA were recorded continuously 19 females 21 during 2-min stressors (mental arithmetic Stroop test). Physical stressor tasks (cold pressor, handgrip exercise, postexercise ischemia) also performed. During first...
Spontaneous sympathetic baroreflex sensitivity (BRS) is a valuable tool for assessing how well the buffers beat-to-beat changes in blood pressure. However, there has yet to be study involving appropriate statistical tests examine stability of BRS within an experimental session and repeatability between separate sessions. The aim this was use intra-class correlations, ordinary least products regression, Bland-Altman analyses spontaneous assessment. In addition, influence recording duration on...
Background: The prevalence of heart failure with preserved ejection fraction (HFpEF) is higher in older women than men, worse clinical outcomes for women. underlying mechanisms are unclear, but aberrant sympathetic neural control may part contribute. Notably, >80% patients HFpEF, particularly women, overweight or obese. This observation important because obesity can augment chronic inflammation, which lead to overactivity. Therefore, we hypothesized that HFpEF would have augmented...
The incidence of cardiovascular events is significantly higher in the morning than other times day. This has previously been associated with poor blood pressure control via cardiac baroreflex. However, it not known whether diurnal variation exists vascular sympathetic baroreflex function, which regulated muscle nerve activity (MSNA). aim this study was to compare sensitivity (BRS) same participants between and afternoon. In 10 (mean age 22 ± 2.9 yrs), continuous measurements pressure, heart...