ORCID Identifier(s)

0000-0002-1624-8778

Graduation Semester and Year

2023

Language

English

Document Type

Dissertation

Degree Name

Doctor of Philosophy in Kinesiology

Department

Kinesiology

First Advisor

Paul J Fadel

Abstract

Non-Hispanic Black women in the United States have a greater prevalence of hypertension compared to non-Hispanic White women, which contributes to a parallel rise in excessive cardiovascular disease burden. Although women of other race/ethnic groups have a lower prevalence of cardiovascular disease compared to their respective male counterparts, Black women have a similar or greater prevalence to Black men, and early cardiovascular disease markers can manifest even in young adulthood. Heightened sympathetic nervous system reactivity and its transduction to blood pressure (i.e., sympathetic vascular transduction) have been proposed as potential mediators of elevated hypertension risk. In addition, it has been reported that Black adults exhibit greater sympathetic and pressor responses to exercise and stress reactivity, although the mechanisms by which Black adults demonstrate greater sympathetic reactivity remains to be elucidated. Importantly, previous work focused on racial disparities in sympathetic nervous system and blood pressure regulation between young Black and White adults have included men only or were not designed to investigate sex differences. This is significant since evidence suggest that men and women demonstrate different mechanisms for blood pressure regulation, which may lead to lower resting sympathetic transduction and sympathetic and blood pressure responses to sympathoexcitatory stressors. Therefore, this dissertation aimed to investigate resting beat-to-beat sympathetic vascular transduction and sympathetic and blood pressure reactivity to exercise and isolated muscle metaboreflex activation in young, healthy Black women. This work expands our current knowledge of neural control of circulation by identifying potential mechanisms contributing to an increased risk of hypertension in Black women later in life. Study 1 determined to investigate whether young healthy Black women exhibit augmented resting beat-to-beat sympathetic vascular transduction compared to young White women. Study 2 determined to investigate whether young Black women exhibit greater sympathetic and blood pressure reactivity to isometric handgrip exercise and isolated muscle metaboreflex activation, compared to young White women. The findings of Study 1 demonstrate that Black women do not exhibit exaggerated resting sympathetic vascular transduction compared to their White counterparts. Suggesting that alterations in sympathetic transduction are not apparent in young, healthy Black women in early adulthood. Secondly, the findings of Study 2 demonstrate that young Black women have similar sympathetic and blood pressure responses to isometric handgrip exercise and isolated muscle metaboreflex activation when compared to young White women, suggesting a preserved pressor response in young Black women. In conclusion, this research provides further insight into the sympathetic control of blood pressure in a highly understudied, at-risk population.

Keywords

Sympathetic vascular transduction, Sympathetic transduction of blood pressure, Racial differences, Neural control, Muscle metaboreflex

Disciplines

Kinesiology | Life Sciences

Comments

Degree granted by The University of Texas at Arlington

31237-2.zip (1337 kB)

Included in

Kinesiology Commons

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