Physiology Commons^™

Post-Transcriptional Regulation Of The Type Iia Sodium-Phosphate Cotransporter By Parathyroid Hormone., Rebecca Dale Murray

Electronic Theses and Dissertations

The type IIa sodium-phosphate cotransporter (Npt2a) is expressed in the apical membrane of the renal proximal tubule and is responsible for the reabsorption of the majority of the filtered load of phosphate. Parathyroid hormone (PTH) is secreted by the parathyroid gland in response to a decrease in serum calcium or an increase in serum phosphorus, and acutely induces phosphaturia through the rapid stimulation of endocytosis of Npt2a and its subsequent lysosomal degradation. Chronic PTH stimulation leads to sustained phosphaturia, but the mechanisms for the chronic regulation of Npt2a by PTH remain unclear. We hypothesize that PTH decreases Npt2a mRNA levels …

Effects Of Step Training On The Kidneys Following Spinal Cord Injury In Rats., Pradeepa Poudyal

Electronic Theses and Dissertations

Detrusor-sphincter dyssynergia after chronic spinal cord injury (SCI) leads to over-distention, high bladder pressures and vesico-ureteric reflux into the kidney, resulting in repeated infections and pyelonephritis. Given the importance/limited knowledge of SCI effects on the upper urinary tract, this study assessed expression of two proteins in the kidneys of contused (T9) male rats relative to controls that are indicative of tissue stress/damage (TGFβ, CD11b). The impact of two therapeutic rehabilitation strategies, 60 minutes of step training and general exercise, was then assessed on these protein levels relative to non-trained SCI controls, plus the effectiveness of a shorter training duration (30 …

The Effect Of A Controlled Frequency Breath Holding Training Program On Running Economy Among Elite College Swimmers., Patrick Sims 1988-

Electronic Theses and Dissertations

Running economy (RE) is the amount of oxygen consumed while running at a submaximal intensity. Along with aerobic capacity (VO2max), RE is an important predictor of running performance. Little research has investigated changes in RE with restricted breathing training [i.e. controlled breath-holding (CFB)] during exercise. RE may improve ~6% amongst a novice swimming cohort through CFB training, but this has not been established in elite swimmers. The purpose was to further establish that CFB training (16 sessions of 12 x 50-m with ~15 seconds rest between each 50-m, using only ~2 breaths per 50-m) can improve RE in 25 elite …

The Role Of Ceramides In Mediating Endotoxin-Induced Mitochondrial Disruption, Melissa Ellen Hansen

Theses and Dissertations

Ceramides are sphingolipids that serve as important second messengers in an increasing number of stress-induced pathways. Ceramide has long been known to affect the mitochondria, altering both morphology and physiology. Lipopolysaccharide (LPS) is a prevalent circulating inflammatory agent in obesity, potentially mediating some of the pathologies associated with weight gain. Given previous findings of TLR4-mediated ceramide accrual and ceramide-mediated mitochondrial disruption, we questioned whether ceramide is necessary for LPS-induced mitochondrial disruption. We found that LPS treatment increased gene transcript levels of ceramide synthesis enzymes and mitochondrial fission proteins and increased ceramide content in cultured myotubes and in mouse tissue. Mitochondrial …

Using The Minimax Accelerometer To Quantify The Demands Of Preseason Training In Ncaa Volleyball: A Descriptive Case-Study Study, Christopher J. Sole, Nobuhisa Yoshida, Bradley A. Alban, Caleb D. Bazyler, Satoshi Mizuguchi

ETSU Faculty Works

Abstract available in the 9th Annual Coaches and Sport Science College.

Exploring The Glucocorticoid Actions Of 1Α-Hydroxycorticosterone (1Α-Oh-B) In The Elasmobranch Fishes, Faith Nichole Lambert

Master's Theses

The corticosteroid 1α-hydroxycorticosterone (1α-OH-B) is unique to the elasmobranch fishes. It is thought that 1α-OH-B acts as both the primary glucocorticoid (GC) and mineralocorticoid (MC) in these fishes, a dual role analogous to that of cortisol in the teleost fishes. The MC characteristics of 1α-OH-B are well supported, but data supporting its GC functions are lacking. In this study, the putative GC actions of 1α-OH-B were examined. The first experiment characterized the physiological stress response of the Atlantic stingray (Dasyatis sabina) to air exposure, with particular regards to the roles of corticosteroids and metabolic fuels. Results demonstrate that …

Insulin Resistance And Muscle Insulin Receptor Substrate-1 Serine Hyperphosphorylation, Charles A. Stuart, Mary E. A. Howell, Brian M. Cartwright, Melanie P. Mccurry, Michelle L. Lee, Michael W. Ramsey, Michael H. Stone

ETSU Faculty Works

Insulin resistance in metabolic syndrome subjects is profound in spite of muscle insulin receptor and insulin-responsive glucose transporter (GLUT4) expression being nearly normal. Insulin receptor tyrosine kinase phosphorylation of insulin receptor substrate-1 (IRS-1) at Tyr896 is a necessary step in insulin stimulation of translocation of GLUT4 to the cell surface. Serine phosphorylation of IRS-1 by some kinases diminishes insulin action in mice. We evaluated the phosphorylation status of muscle IRS-1 in 33 subjects with the metabolic syndrome and seventeen lean controls. Each underwent euglycemic insulin clamps and a thigh muscle biopsy before and after 8 weeks of either strength or …

An Exploratory Study On The Use Of Concentric Velocities In The Back Squat As A Monitoring Tool, Kevin M. Carroll, Josh D. Christovich, Caleb D. Bazyler, Nicholas J. Fiolo, George K. Beckham, Kimitake Sato

ETSU Faculty Works

Abstract available in the 9th Annual Coaches and Sport Science College .

Central Administration Of Neuropeptide Y (Npy) And Vasotocin 4 Receptor (Vt4r/V1ar) Antagonists On Food Intake And A Stress Response In Chicks, Megan Ann Hancock

Graduate Theses and Dissertations

The objective of this study was to determine the central effect of the VT4R antagonists (SR-49059 and H-5350 (Manning compound)) on corticosterone (CORT) levels during stress and food intake. A 22-gauge stainless steel guide cannula was surgically implanted into the lateral ventricle of the birds. A preliminary study was done to test the antagonists and their role on food intake. Birds were injected with saline, NPY (4µg), NPY (4µg)+SR-49059 (250ng), or NPY (4µg)+Manning compound (250ng). Birds injected with saline had the lowest 1h food intake (17.7g1.6). Birds injected with NPY+saline had a significantly higher intake (27.1g 1.0), which was enhanced …

Analysis Of Changes In Strength, Explosiveness, And Agility Performance Over An Ncaa Division I Tennis Career: A Case Study, Caleb D. Bazyler, Jacob R. Goodin, George Beckham, H. Santana, M. Swartz, Ashley A. Kavanaugh

ETSU Faculty Works

Abstract available in the 9th Annual Coaches and Sport Science College .

Regulation Of Functional Expression Of Mechanosensitive Trpv4 Channel In The Distal Nephron By Dietary Potassium And Sodium Intake, Nabila Boukelmoune

Dissertations and Theses (Open Access)

The Ca²⁺-permeable TRPV4 channel is predominantly expressed in the distal nephron (DN) and its activity is essential for [Ca²⁺]_i elevations in response to increased tubular flow. Here, I probed the physiological mechanisms controlling TRPV4 function and expression in the DN. I found that renal TRPV4 expression and mRNA levels were significantly increased by high K⁺ diet (5%) and decreased by dietary K⁺ restriction (0.003%). In contrast, variations in Na⁺ regimen had no apparent effect on TRPV4 expression and mRNA levels. Regulation of TRPV4 protein expression by K⁺ diet was independent of …

Hif-1Α In The Heart: Provision Of Ischemic Cardioprotection And Remodeling Of Nucleotide Metabolism, Joe Wu

Electronic Theses and Dissertations

In our studies we found that stabilized expression of HIF-1α in heart led to better recovery of function and less tissue death after 30 minutes of global ischemia, via mechanisms that preserve the mitochondrial polarization. Our group previously showed that HIF-1α conferred ischemic tolerance by allowing cardiomyocytes to use fumarate as an alternative terminal electron acceptor to sustain anaerobic mitochondrial polarization. The source of fumarate was identified as the purine nucleotide cycle (PNC). Here we discovered that HIF-1α upregulates AMP deaminase 2 (AMPD2), the entry point to the PNC. The combination of glycolysis and the PNC may protect the heart's …

Functional Characterization Of The Arginine Vasotocin 4 Receptor (Vt4r) In Sensory Circumventricular Organs Of The Chicken Gallus Gallus, Nguiessan Alphonse Aman

Graduate Theses and Dissertations

Past studies have shown that the avian vasotocin 4 receptor (VT4R), homologous to the mammalian arginine vasopressin receptor 1a (V1aR/AVPR1A) is involved in immobilization stress. It was not known, however, whether the receptor is also associated with osmotic stress, and if so, what brain regions may be involved. Four treatment groups of chicks were used for the study. One group was subjected to 1h immobilization stress and two groups were administered intraperitoneal injection of 3 M NaCl or 0.15 M NaCl. One additional group served as controls. After 1 h, blood samples were taken for the determination of plasma levels …

Extent Of Cysteine Modification Of Snap-25 In Vitro, Alex Mcgregor Dabell

Theses and Dissertations

Exocytosis, the fusion of a vesicle to a cellular membrane, involves a protein named SNAP-25. This protein, containing two alpha helices connected with a linker region, is localized to the cell membrane via palmitic acids attached to the cysteine residues of its linker region in a process called palmitoylation. Are cysteine residues of the SNAP-25 linker region palmitoylated in an ordered manner and to a particular extent? The answer to this question may give insight into the regulated nature of exocytosis. While it is generally accepted that SNAP-25 must be palmitoylated in order to perform its exocytotic functions, the details …

Alcohol Modulation Of Dopamine Release, Nathan Dan Schilaty

Theses and Dissertations

The mesolimbic dopamine (DA) system projects from the ventral tegmental area (VTA) to structures associated with the limbic system, primarily the nucleus accumbens (NAc). This system has been implicated in the rewarding effects of drugs of abuse. Many drugs of abuse act in the VTA, the NAc, or both. Dopamine neurons in the VTA that project to the NAc, and the GABA neurons that inhibit DA neurons locally in the VTA or project to the NAc, play an important role in mediating addiction to various drugs of abuse, in particular alcohol. There is a growing body of evidence of co-dependence …

Central Role Of Carotid Body Chemoreceptors In Disordered Breathing And Cardiorenal Dysfunction In Chronic Heart Failure., Noah J. Marcus, Rodrigo Del Rio, Harold D. Schultz

Journal Articles: Cellular & Integrative Physiology

Oscillatory breathing (OB) patterns are observed in pre-term infants, patients with cardio-renal impairment, and in otherwise healthy humans exposed to high altitude. Enhanced carotid body (CB) chemoreflex sensitivity is common to all of these populations and is thought to contribute to these abnormal patterns by destabilizing the respiratory control system. OB patterns in chronic heart failure (CHF) patients are associated with greater levels of tonic and chemoreflex-evoked sympathetic nerve activity (SNA), which is associated with greater morbidity and poor prognosis. Enhanced chemoreflex drive may contribute to tonic elevations in SNA by strengthening the relationship between respiratory and sympathetic neural outflow. …

In Vivo Identification Of Eugenol-Responsive And Muscone-Responsive Mouse Odorant Receptors, Timothy S. Mcclintock, Kaylin Adipietro, William B. Titlow, Patrick Breheny, Andreas Walz, Peter Mombaerts, Hiroaki Matsunami

Physiology Faculty Publications

Our understanding of mammalian olfactory coding has been impeded by the paucity of information about the odorant receptors (ORs) that respond to a given odorant ligand in awake, freely behaving animals. Identifying the ORs that respond in vivo to a given odorant ligand from among the ∼1100 ORs in mice is intrinsically challenging but critical for our understanding of olfactory coding at the periphery. Here, we report an in vivo assay that is based on a novel gene-targeted mouse strain, S100a5-tauGFP, in which a fluorescent reporter selectively marks olfactory sensory neurons that have been activated recently in vivo. Because each …

Cannabinoid Receptor 2 Agonist Attenuates Pain Related Behavior In Rats With Chronic Alcohol/High Fat Diet Induced Pancreatitis, Liping Zhang, Robert H. Kline Iv, Terry A. Mcnearney, Michael P. Johnson, Karin Westlund High

Physiology Faculty Publications

BACKGROUND: Chronic Pancreatitis (CP) is a complex and multifactorial syndrome. Many contributing factors result in development of dysfunctional pain in a significant number of patients. Drugs developed to treat a variety of pain states fall short of providing effective analgesia for patients with chronic pancreatitis, often providing minimal to partial pain relief over time with significant side effects. Recently, availability of selective pharmacological tools has enabled great advances in our knowledge of the role of the cannabinoid receptors in pathophysiology. In particular, cannabinoid receptor 2 (CB2) has emerged as an attractive target for management of chronic pain, as demonstrated in …

The Reduction Of Metabolic Cost While Using Handrail Support During Inclined Treadmill Walking Is Dependent On The Handrail-Use Instruction, Cory Hofmann, Connor Dougherty, Hagop Abkarian, Michele Fox, Paul Juris

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 339-345, 2014. Inclined treadmill walking is a commonly performed activity to increase cardiovascular health. Handrail support on a treadmill provides an individual the opportunity to change their posture with respect to the walking surface. Differences in metabolic cost during inclined walking due to postural changes with handrail use are unknown. To test the hypothesis that metabolic cost will differ depending on how handrail support is used, respiratory gas analysis was performed during inclined walking in 13 healthy subjects. Energy expenditure was quantified while each subject walked in four conditions: 5% incline unsupported, 10% …

Functional Morphology And Feeding Mechanics Of Billfishes, María Laura Habegger

USF Tampa Graduate Theses and Dissertations

Billfishes (marlins, spearfishes, sailfishes and swordfish) are one of the fastest and largest marine apex predators, and perhaps their most recognizable attribute is their bill or rostrum. The proposed function for this novel structure has ranged from hydrodynamic enhancement to defensive weaponry. However, the most supported hypothesis for its function has been linked to feeding. Billfishes have been observed to subdue their prey with their rostrum, either stunning or cutting them into pieces before ingestion. Due to their large body sizes and pelagic lifestyles a thorough investigation of the function of this structure has been logistically challenging. The goal of …

Lactate Threshold Comparison In Anaerobic Vs. Aerobic Athletes And Untrained Subjects, Matt Green, Jared Hornsby, Robert Pritchett, Kelley Pritchett

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 329-338, 2014. This study compared VO₂ max, lactate threshold (LT) and VO₂ at LT (VO_2LT) among aerobic athletes (ARA) (n=10), anaerobic athletes (ANA) (n=9) and untrained participants (UTS) (n=7). From a treadmill test to exhaustion, VO₂ max and LT (4 mmol·L^-1 blood lactate concentration) were assessed. Analysis of variance showed VO₂ max (ml·kg^-1·min^-1) was significantly greater for ARA (67.6 ± 9.4) than ANA (53.4 ± 6.4) and UTS (44.9 + 6.9), with ANA significantly greater than UTS. LT for ARA (82.9 + …

Longitudinal Trajectories Of Cholesterol From Midlife Through Late Life According To Apolipoprotein E Allele Status, Brian Downer, Steven Estus, Yuriko Katsumata, David W. Fardo

Physiology Faculty Publications

Background: Previous research indicates that total cholesterol levels increase with age during young adulthood and middle age and decline with age later in life. This is attributed to changes in diet, body composition, medication use, physical activity, and hormone levels. In the current study we utilized data from the Framingham Heart Study Original Cohort to determine if variations in apolipoprotein E (APOE), a gene involved in regulating cholesterol homeostasis, influence trajectories of total cholesterol, HDL cholesterol, and total: HDL cholesterol ratio from midlife through late life.

Methods: Cholesterol trajectories from midlife through late life were modeled using generalized …

Intercollegiate Cross Country Competition: Effects Of Warm-Up And Racing On Salivary Levels Of Cortisol And Testosterone, Kathleen V. Casto, Christopher Elliott, David A. Edwards

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 318-328, 2014. Team intercollegiate athletic competition is associated with an increase in salivary cortisol (C) and testosterone (T) in men and women. The present study was designed to determine the hormonal effects of warm-up and racing in cross country runners – a sport that has both individual and team components. Members of the Emory University men’s and women’s varsity cross country teams gave saliva samples before warm-up, after warm-up, and immediately after the finish of each of two intercollegiate invitational meets held one year apart in the same setting (2010, N = 10 …

Vo2 Reserve Vs. Heart Rate Reserve During Moderate Intensity Treadmill Exercise, Tanner J. Solheim, Brad G. Keller, Charles J. Fountaine

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 311-317, 2014. ­VO₂ and heart rate (HR) are widely used when determining appropriate training intensities for clinical, healthy, and athletic populations. It has been shown that if the % reserve (%R) is used, rather than % of max, HR and VO₂ can be used interchangeably to accurately prescribe exercise intensities. Thus, heart rate reserve (HRR) can be prescribed if VO₂ reserve (VO₂R) is known. Therefore, the purpose of this study was to compare VO₂ R and HRR during moderate intensity exercise (50%R). Physically active college students …

Muscle Activity In Single- Vs. Double-Leg Squats, Bradley A. Deforest, Gregory S. Cantrell, Brian K. Schilling

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 302-310, 2014. Muscular activity, vertical displacement and ground reaction forces of back squats (BS), rear-leg elevated split squats (RLESS) and split squats (SS) were examined. Nine resistance-trained men reported for two sessions. The first session consisted of the consent process, practice, and BS 1-repetition maximum testing. In the second session, participants performed the three exercises while EMG, displacment and ground reaction force data (one leg on plate) were collected. EMG data were collected from the gluteus maximus (GMX), biceps femoris (BF), semitendinosus (ST), rectus femoris (RF), vastus lateralis (VL), vastus medialis (VM), tibialis …

Occupational Sitting And Physical Activity Among University Employees, Charles J. Fountaine, Meredith Piacentini, Gary A. Liguori

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 295-301, 2014. The prevalence of overweight and obese in the U.S. has been thoroughly documented. With the advent of inactivity physiology research and the subsequent interest in sedentary behavior, the work environment has come under closer scrutiny as a potential opportunity to reverse inactivity. Therefore, the purpose of this study was to determine the sitting and physical activity (PA) habits among different classifications of university employees. University employees (n=625) completed an online survey based on the Occupational Sitting and Physical Activity Questionnaire (OSPAQ). Participants were instructed to describe time spent sitting, standing, walking, …

Time Spent In Mvpa During Exergaming With Xbox Kinect In Sedentary College Students, Chie Yang, Zachary Wickert, Samantha Roedel, Alexandria Berg, Alex Rothbauer, Marquell Johnson, Donald Bredle

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 286-294, 2014. The primary purpose of this study was to determine the amount of time spent in moderate-to-vigorous physical activity (MVPA) during a 30-minute bout of exergaming with the Xbox Kinect game console in sedentary college-aged students. A secondary purpose was to examine enjoyment level of participation in the selected exergame. Twenty college-aged students (14 females and 6 males) who self-reported being physically inactive and having no prior experience with the Xbox Kinect game “Your Shape Fitness Evolved 2012” Break a Sweat activity participated in the study. Participants came into the lab on …

Can Resistance Training Contribute To The Aerobic Components Of The Physical Activity Guidelines?, Travis J. Hrubeniuk, Neal Prokop, Semone Myrie, Martin Sénéchal, Danielle R. Bouchard

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 278-285, 2014. To evaluate if resistance training can reach Moderate to Vigorous Intensity (MVI) and contribute to the aerobic component of the international physical activity guidelines. Sixteen participants aged between 20 and 35 were recruited. Heart rate was recorded by heart rate monitor during a resistance training program. Based on maximal heart rate, time spent at MVI (55-69% of maximal heart rate) was calculated. Participants displayed a HR equal or above MVI for 51.5% ± 21.7% of time. When stratifying by lower and upper body sessions, that proportion was median (25-75th); 75.0% (32.5%-89.2%) …

The Acute Effects Of A Dynamic Stretching Protocol On Wingate Performance, Autumn S. Gipson Ms., Jamarious Jones, Elise N. Ritchey, Colby Murphy, Hope Grimes, John M. Coons

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 271-277, 2014. Stretching before performing anaerobic activity has been a highly debated subject, with studies finding differing results depending on the type (static, dynamic, etc.) and duration of the stretch. Furthermore, the effects of dynamic stretching (DS) on anaerobic performance have been minimally researched. The purpose of this study was to examine the effects a DS protocol had on power performance using a Wingate test (WAnT). College-aged male subjects were recruited for this study. Prior to experimental trials, subjects performed a familiarity WAnT trial. Subjects then performed the WAnT two more times, once …

The Relationship Between Change Of Direction Speed In The Frontal Plane, Power, Reactive Strength, And Strength, Brian T. Mccormick, James C. Hannon, Charlie A. Hicks-Little, Maria Newton, Barry Shultz, Nicole Detling, Warren B. Young

International Journal of Exercise Science

International Journal of Exercise Science 7(4) : 260-270, 2014. Change-of-direction speed (CODS) is an important quality to performance in multi-direction sports. The relationship between CODS in the frontal plane and power, strength, and reactive strength is largely unstudied. Twenty-three male college students participated in this study. The study used a Pearson’s product-moment correlation to measure the relationship between CODS, power, strength, and reactive strength. A lateral shuffle test was used as the measure of CODS. A lateral hop for distance was used as the measure of power in the frontal plane. A countermovement vertical jump test was used as the …