Cardiovascular System Commons^™

Vascular Regulation Via Kir Channels And Na+ /K+-Atpase, Anne R. Crecelius, Frank A. Dinenno

Health and Sport Science Faculty Publications

Despite the longstanding knowledge that blood flow increases in proportion to metabolic activity of skeletal muscle, the underlying mechanisms that govern this response have only recently been identified.¹ Given the role of endothelial cells in mediating exercise hyperemia,² interest has been focused on endothelium-derived vasodilation occurring via the synthesis of nitric oxide (NO) and vasodilating prostaglandins (PGs; i.e. prostacyclin) or endothelium- derived hyperpolarization. A number of studies performed in humans have established a minimal-to-modest role for NO and PGs during mild- and moderate- intensity exercise. In animal preparations, prevention of hyperpolarization attenuates contraction-induced hyperemia; however, performing similar studies …

Intravascular Atp And The Regulation Of Blood Flow And Oxygen Delivery In Humans, Anne R. Crecelius, Brett S. Kirby, Frank A. Dinenno

Health and Sport Science Faculty Publications

Regulation of vascular tone is a complex response that integrates multiple signals which allow for blood flow and oxygen supply to appropriately match oxygen demand. Here, we discuss the potential role of intravascular ATP as a primary factor in these responses and propose that deficient ATP release may contribute to impairments in vascular control exhibited in aged and diseased populations.

Kir Channel Activation Contributes To Onset And Steady-State Exercise Hyperemia In Humans, Anne R. Crecelius, Gary J. Luckasen, Dennis G. Larson, Frank A. Dinenno

Health and Sport Science Faculty Publications

We tested the hypothesis that activation of inwardly rectifying potassium (K_IR) channels and Na⁺-K⁺-ATPase, two pathways that lead to hyperpolarization of vascular cells, contributes to both the onset and steady-state hyperemic response to exercise. We also determined whether after inhibiting these pathways nitric oxide (NO) and prostaglandins (PGs) are involved in the hyperemic response. Forearm blood flow (FBF; Doppler ultrasound) was determined during rhythmic handgrip exercise at 10% maximal voluntary contraction for 5 min in the following conditions: control [saline; trial 1 (T1)]; with combined inhibition of K_IR channels and Na …

Alterations And Specifications Of Excess Post-Exercise Oxygen Consumption: A Review, Genevieve Kocoloski, Anne R. Crecelius

Health and Sport Science Faculty Publications

This review describes oxygen consumption, both in terms of a goal of weight management and aerobic training. It introduces excess postexercise oxygen consumption (EPOC) and the benefits that can come from it. EPOC can aid in weight management as a means to continue to expend energy even after exercise has ceased. This review also discusses the many determinants of EPOC and analyzes the effects of various conditions on the elevated consumption. Such conditions include duration and intensity of exercise, training status, and supplementation. Later discussed are the possible underlying mechanisms and how they are responsible for EPOC. Although they have …

Reactive Hyperemia Occurs Via Activation Of Inwardly Rectifying Potassium Channels And Na+/K+-Atpase In Humans, Anne R. Crecelius, Jennifer C. Richards, Gary J. Luckasen, Dennis G. Larson, Frank A. Dinenno

Health and Sport Science Faculty Publications

Rationale: Reactive hyperemia (RH) in the forearm circulation is an important marker of cardiovascular health, yet the underlying vasodilator signaling pathways are controversial and thus remain unclear.

Objective: We hypothesized that RH occurs via activation of inwardly rectifying potassium (K_IR) channels and Na⁺/K⁺-ATPase and is largely independent of the combined production of the endothelial autocoids nitric oxide (NO) and prostaglandins in young healthy humans.

Methods and Results: In 24 (23±1 years) subjects, we performed RH trials by measuring forearm blood flow (FBF; venous occlusion plethysmography) after 5 minutes of arterial occlusion. In protocol 1, …

Field Testing Adolescent Females For Cardiovascular Disease Risk, C. Jayne Brahler, Wesley R. Stephens, Betsy Donahoe Fillmore

Physical Therapy Faculty Publications

Over-fatness and poor cardiovascular (CV) fitness are well-documented risk factors for cardiovascular disease (CVD) in adults, but less is known about their association with disease risk in adolescents. This study aimed to determine the relationship between anthropometrics, fitness, and CVD risk.

Six anthropometric indicators of body fatness, seven measures of fitness, and seven metabolic and hemodynamic CVD risk factors were measured in a convenience sample of 28 female high school students (15-18 years of age). A tally was made of the number of factors for which each subject was outside the normal reference range (CVD risk).

Correlation analyses were completed …

The Mind-Body Connection: The Association Between Adolescent Locus Of Control And Indicators Of Physical Health, C. Jayne Brahler, James Cropper

Physical Therapy Faculty Publications

Locus of control (LOC) describes an individual’s generalized beliefs or expectancies that their reinforcements are under internal versus external control (1). An individual exhibits either an internal or external LOC. This study examines the link between LOC and selected health risk factors in adolescents. A convenience sample of 167 high school physical education students completed a 13-item LOC questionnaire based on Rotter’s 1966 instrument.

Various anthropometric measurements, blood pressure, body mass index (BMI), and body fat were recorded on all subjects. A subsample of 61 female students received blood chemistry analysis that included a lipid profile, hemoglobin A1c (HbA1c), Apo …

Disaggregating The Relative Influence Of Genetic, Environmental And Individual Factors On Ldl And Hdl Cholesterols And Bmi For A Sample Of African American (Aa) Mothers And Daughters, C. Jayne Brahler, Jewel Harden, Michelle Mchone, Matthew Soules, Eric Evans, Ann Alyanak, Fred Diakpieng, Paul M. Vanderburgh

Health and Sport Science Faculty Publications

There are many reports about the associations between blood lipids, body mass index (BMI) and dietary cholesterol intakes both within the individual and between related individuals. The purpose of this descriptive research project was to investigate the relationships between LDL and HDL cholesterols, body mass index and dietary cholesterol intakes for a sample of African American (AA) mothers and their daughters and to attempt to separate the contribution of genetic versus environmental factors. Mother and daughter participants (n =42 and 66, respectively) were 12-14-hours fasted when blood samples were drawn, heights and weights measured, and 24 hour food recalls completed.

Qtc Is Associated With Obesity And Physical Activity Level For African American Females, C. Jayne Brahler

Health and Sport Science Faculty Publications

Long QT syndrome (LQTS) is an independent risk factor for cardiovascular or ischemic disease mortality. Obesity as a cause for acquired LQTS in otherwise healthy individuals is rapidly gaining the attention of the scientific community. African American people have a higher incidence of obesity compared to Caucasians, yet race-specific information is not available for their prevalence of LQTS. Chronic physical activity can help reduce the incidence of obesity, yet little is known about the effects of chronic physical activity on acquired LQTS. Subjects in this study were a volunteer sample of African American mothers (21-53 yr, n = 44) and …