Neural Control of Kidney Blood Flow During Exercise in African American Adults
- Conditions
- Healthy
- Interventions
- Other: Acute exerciseOther: Cold pressor testOther: Mental stress test
- Registration Number
- NCT03981640
- Lead Sponsor
- University of Massachusetts, Boston
- Brief Summary
African American (AA) adults have a greater prevalence of developing cardiovascular and renal disease (CVRD) than White (W) adults. Elevated sympathetic nervous system activity is associated with increased incidence of CVRD. Physical exertion, such as exercise, acutely increases sympathetic nervous system activity directed towards the kidneys, resulting in renal vasoconstriction and reduced renal blood flow (RBF). However, the acute renal vasoconstrictor response to any sympathetic nervous system activation has not been investigated to date in AA adults. During sympathetic nervous system activation such as exercise, sympathetic outflow to the kidneys in AA adults might be exaggerated, contributing to greater renal vasoconstriction and a larger reduction in RBF. Over time, this exaggerated neurovascular response to sympathetic activation could have a negative cumulative effect on the kidneys, which could be a contributing factor to the greater incidence of CVRD in this population. Therefore, this study aims to examine the renal vasoconstrictor response to sympathetic stressors in healthy AA adults prior to development of CVRD to test the hypotheses that the renal vasoconstrictor response to acute dynamic exercise, as well as a cold pressor and mental stress tests, is exaggerated in healthy young AA compared to W adults. To test these hypotheses, the investigators will measure RBF and blood pressure at rest and during cycling exercise and a cold pressor and mental stress tests to calculate renal vascular resistance responses to these acute interventions. Using the highly innovative approach of Doppler ultrasound to measure RBF during exercise and non-exercise sympathetic stressors non-invasively and with high temporal resolution will enable us to assess the renal vasoconstrictor response to sympathetic stressors in healthy AA adults prior to development of CVRD, so the underlying integrative physiological responses to sympathetic activation in AA adults can be understood. Findings from this study in this understudied yet clinically significant area will contribute to the ultimate goal of creating and implementing treatment strategies to reduce the risk of developing CVRD in AA adults.
- Detailed Description
African American (AA) adults have a greater prevalence of developing cardiovascular and renal disease (CVRD) than White (W) adults. Elevated sympathetic nervous system activity is associated with increased incidence of CVRD. Physical exertion, such as exercise, acutely increases sympathetic nervous system activity directed towards the kidneys, resulting in renal vasoconstriction and reduced renal blood flow (RBF). Limited research shows that healthy young AA adults exhibit exaggerated sympathetic responsiveness both at rest and during sympathetic activation, which may be a major contributor to the increased risk of CVRD in this population. However, the acute renal vasoconstrictor response to any sympathetic nervous system activation has not been investigated to date in AA adults. During sympathetic nervous system activation such as exercise, sympathetic outflow to the kidneys in AA adults might be exaggerated, contributing to greater renal vasoconstriction and a larger reduction in RBF. Over time, this exaggerated neurovascular response to sympathetic activation could have a negative cumulative effect on the kidneys, which could be a contributing factor to the greater incidence of CVRD in this population.
Therefore, this study aims to examine the renal vasoconstrictor response to sympathetic stressors in healthy AA adults prior to development of CVRD, which will be achieved via two Specific Aims. In Specific Aim 1, the investigators will test the hypothesis that the renal vasoconstrictor response to acute dynamic exercise is exaggerated in healthy young AA compared to W adults. Specifically, the investigators will measure RBF and blood pressure at rest and during cycling exercise to calculate renal vascular resistance responses to exercise, enabling us to test the hypothesis that healthy young AA adults exhibit an exaggerated renal vasoconstrictor response to acute cycling exercise compared to healthy young W adults. In Specific Aim 2, the investigators will test the hypothesis that the renal vasoconstrictor response to non-exercise sympathetic stressors is exaggerated in healthy young AA compared to W adults. Specifically, the investigators will measure RBF and blood pressure at rest and during a cold pressor and mental stress tests to calculate renal vascular resistance responses to these non-exercise sympathetic stressors, enabling us to test the hypothesis that healthy young AA adults exhibit exaggerated renal vasoconstrictor responses to non-exercise sympathetic stressors compared to healthy young W adults.
Using the highly innovative approach of Doppler ultrasound to measure RBF during exercise and non-exercise sympathetic stressors non-invasively and with high temporal resolution will enable us to assess the renal vasoconstrictor response to sympathetic stressors in healthy AA adults prior to development of CVRD, so the underlying integrative physiological responses to sympathetic activation in AA adults can be understood. Findings from this study in this understudied yet clinically significant area will contribute to the ultimate goal of creating and implementing treatment strategies to reduce the risk of developing CVRD in AA adults.
Recruitment & Eligibility
- Status
- RECRUITING
- Sex
- All
- Target Recruitment
- 32
- Self-report as either African American or White racial identity
- Born in United States
- Both biological parents identify as same racial identity as participant
- Recreationally active (participating in physical activity for at least 20 minutes per day, at least three times per week, but not training for competitive events)
- Fluent in English
- Hispanic or Latino
- Females who are pregnant or lactating
- Cardiovascular or renal disease
- Hypertension (blood pressure of more than or equal to 130/80 mmHg)
- Diabetes
- Obesity (body mass index of more than or equal to 30 kg/m2)
- Smoker/Tobacco user
- Acute medical conditions
- Taking prescribed cardiovascular, antihypertensive, or renal medications
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description African American Adults Cold pressor test African American adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded. White Adults Cold pressor test White adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded. White Adults Mental stress test White adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded. African American Adults Acute exercise African American adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded. African American Adults Mental stress test African American adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded. White Adults Acute exercise White adults will undergo the interventions of acute exercise, a cold pressor test, and a mental stress test while beat-to-beat renal blood flow velocity, mean arterial blood pressure, and heart rate are recorded.
- Primary Outcome Measures
Name Time Method Change in renal vascular resistance during acute exercise Pre-acute exercise and during steady-state exercise For the acute exercise intervention, the percent change from pre-acute exercise to during steady-state exercise will be assessed.
Change in renal vascular resistance during cold pressor test Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test For the cold pressor test intervention, the percent change from pre-cold pressor test to 30-second intervals during the cold pressor test will be assessed.
Change in renal vascular resistance during mental stress test Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test For the mental stress test intervention, the percent change from pre-mental stress test to 1-minute intervals during the mental stress test will be assessed.
- Secondary Outcome Measures
Name Time Method Change in diastolic blood pressure during acute exercise Pre-acute exercise and during steady-state exercise For the acute exercise intervention, the absolute change from pre-acute exercise to during steady-state exercise will be assessed.
Change in stroke volume during acute exercise Pre-acute exercise and during steady-state exercise For the acute exercise intervention, the absolute change from pre-acute exercise to during steady-state exercise will be assessed.
Change in renal blood flow velocity during cold pressor test Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test For the cold pressor test intervention, the absolute change from pre-cold pressor test to 30-second intervals during the cold pressor test will be assessed.
Change in heart rate during cold pressor test Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test For the cold pressor test intervention, the absolute change from pre-cold pressor test to 30-second intervals during the cold pressor test will be assessed.
Change in renal blood flow velocity during mental stress test Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test For the mental stress test intervention, the absolute change from pre-mental stress test to 1-minute intervals during the mental stress test will be assessed.
Change in mean arterial blood pressure during mental stress test Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test For the mental stress test intervention, the absolute change from pre-mental stress test to 1-minute intervals during the mental stress test will be assessed.
Change in renal blood flow velocity during acute exercise Pre-acute exercise and during steady-state exercise For the acute exercise intervention, the absolute change from pre-acute exercise to during steady-state exercise will be assessed.
Change in mean arterial blood pressure during acute exercise Pre-acute exercise and during steady-state exercise For the acute exercise intervention, the absolute change from pre-acute exercise to during steady-state exercise will be assessed.
Change in systolic blood pressure during acute exercise Pre-acute exercise and during steady-state exercise For the acute exercise intervention, the absolute change from pre-acute exercise to during steady-state exercise will be assessed.
Change in heart rate during acute exercise Pre-acute exercise and during steady-state exercise For the acute exercise intervention, the absolute change from pre-acute exercise to during steady-state exercise will be assessed.
Change in cardiac output during acute exercise Pre-acute exercise and during steady-state exercise For the acute exercise intervention, the absolute change from pre-acute exercise to during steady-state exercise will be assessed.
Change in total peripheral resistance during acute exercise Pre-acute exercise and during steady-state exercise For the acute exercise intervention, the absolute change from pre-acute exercise to during steady-state exercise will be assessed.
Change in mean arterial blood pressure during cold pressor test Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test For the cold pressor test intervention, the absolute change from pre-cold pressor test to 30-second intervals during the cold pressor test will be assessed.
Change in systolic blood pressure during cold pressor test Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test For the cold pressor test intervention, the absolute change from pre-cold pressor test to 30-second intervals during the cold pressor test will be assessed.
Change in diastolic blood pressure during cold pressor test Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test For the cold pressor test intervention, the absolute change from pre-cold pressor test to 30-second intervals during the cold pressor test will be assessed.
Change in cardiac output during cold pressor test Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test For the cold pressor test intervention, the absolute change from pre-cold pressor test to 30-second intervals during the cold pressor test will be assessed.
Change in total peripheral resistance during mental stress test Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test For the mental stress test intervention, the absolute change from pre-mental stress test to 1-minute intervals during the mental stress test will be assessed.
Change in stroke volume during cold pressor test Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test For the cold pressor test intervention, the absolute change from pre-cold pressor test to 30-second intervals during the cold pressor test will be assessed.
Change in total peripheral resistance during cold pressor test Pre-cold pressor test to after 30, 60, 90, and 120 seconds of cold pressor test For the cold pressor test intervention, the absolute change from pre-cold pressor test to 30-second intervals during the cold pressor test will be assessed.
Change in diastolic blood pressure during mental stress test Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test For the mental stress test intervention, the absolute change from pre-mental stress test to 1-minute intervals during the mental stress test will be assessed.
Change in systolic blood pressure during mental stress test Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test For the mental stress test intervention, the absolute change from pre-mental stress test to 1-minute intervals during the mental stress test will be assessed.
Change in heart rate during mental stress test Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test For the mental stress test intervention, the absolute change from pre-mental stress test to 1-minute intervals during the mental stress test will be assessed.
Change in cardiac output during mental stress test Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test For the mental stress test intervention, the absolute change from pre-mental stress test to 1-minute intervals during the mental stress test will be assessed.
Change in stroke volume during mental stress test Pre-mental stress test to after 1, 2, 3, 4, and 5 minutes of mental stress test For the mental stress test intervention, the absolute change from pre-mental stress test to 1-minute intervals during the mental stress test will be assessed.
Trial Locations
- Locations (1)
University of Massachusetts Boston
🇺🇸Boston, Massachusetts, United States