Medicine and Health Sciences Commons^™

Sexual Dimorphism Of Glomerular Capillary Morphology In Rats, Zackarias Coker

Undergraduate Honors Theses

Chronic kidney disease (CKD) progresses faster in males than females; however, the underlying mechanisms remain poorly understood. Sex differences in glomerular capillary morphology has been hypothesized to contribute, in part, to the increased susceptibility to hypertension-induced renal injury and CKD progression in males, but this has not been investigated. The goal of the present study was to assess glomerular capillary morphology in male vs. female rats with intact kidneys and after uninephrectomy (UNX). We hypothesized that glomerular capillary radii (R_CAP) and length (L_CAP) would be greater in male rats.

Male (n=4) and female (n=4) with intact …

The Impact Of Long Term Ovariectomy On Diastolic Function And Fibrosis Following Chronic Sympathetic Stimulation In Mice, Erin Moore

Undergraduate Honors Theses

Cardiovascular Disease (CVD) accounts for the leading number of deaths worldwide. Prior to menopause, women exhibit lower rates of CVD compared to age-matched men, however, risks for women increase with menopause. Studies show estrogen loss and age exacerbating cardiac β-adrenergic receptor (β-AR) signaling and contractile function. We therefore hypothesized that prolonged estrogen deficiency and chronic β-adrenergic stimulation cause decreases in cardiac function and increases in fibrosis in aged female hearts. Female mice underwent either an ovariectomy (OVX) or a control SHAM surgery at 10 weeks old and were infused with Isoproterenol for three days via mini osmotic pumps in …

Neuroanatomical Distribution Of Neurons Within The Hypothalamic Paraventricular Nucleus That Project To The Brainstem Rostral Ventrolateral Medulla, Nicolas Fuller

Undergraduate Honors Theses

The sympathetic nervous system is important in maintaining cardiovascular homeostasis. Elevated cardiovascular-related sympathetic activity can lead to neurogenic hypertension and a host of other serious cardiac-related abnormalities. The paraventricular nucleus (PVN) of the hypothalamus plays an important role in sympathetic cardiovascular regulation. Neurons from the PVN project to the rostral ventrolateral medulla (RVLM), which is the main brain stem sympathetic cardiovascular control center. While RVLM-projecting PVN neurons have been well characterized, the topographical organization within the PVN subnuclei is still not fully known. This neuroanatomical study aimed to map the topographical distribution of RVLM-projecting PVN neurons. Four different carboxylate FluoSphereTM …

Role Of Ataxia Telangiectasia Mutated Kinase In Western-Type Diet-Induced Cardiac Outcomes Under Basal And Ischemic Conditions, Mary Wingard

Electronic Theses and Dissertations

Ataxia-telangiectasia mutated kinase (ATM), a serine/threonine kinase, plays a role in DNA damage repair, redox sensing, and metabolism. In the heart, ATM contributes significantly in the myocardial infarction (MI)-induced cardiac remodeling with effects on fibrosis, hypertrophy, apoptosis and inflammation. This study investigates the role of ATM deficiency in 14 weeks Western-type diet (WD)-induced cardiac outcomes prior to and 1-day post-MI in a sex-specific manner using wild-type (WT) and ATM heterozygous knockout (hKO) mice. In male mice, ATM deficiency induced rapid body weight gain and preload-associated dysfunction, while WT mice displayed afterload-associated dysfunction 14 weeks post-WD. Myocyte apoptosis and hypertrophy were …

Preserving Safety While Upholding The Integrity Of Medical Education And Practical Skills: The Impact Of Covid-19 On Teaching Human Anatomy, Anna Cowan

Undergraduate Honors Theses

The global pandemic caused by COVID-19 placed constraints on several aspects of normal life, especially those of higher level education. While many programs moved to teaching in a strictly online format, there are some courses in which this structure was not appropriate. This study observed the outcome of the adapted course structure employed at Quillen College of Medicine during their Gross Human Anatomy course. Through a voluntary survey and multiple independent t-tests, it was demonstrated that the students who took the adapted course performed, on average, 2 points lower on each exam than previous classes. Also, this study showed that …

Ctrp3 And Alcoholic Liver Disease In Female Mice, Callie Root

Undergraduate Honors Theses

C1q TNF Related Protein 3 (CTRP3), is a cytokine that is primarily secreted from adipose tissue, which classifies it as an adipokine. Our previous research has shown that CTRP3 prevents alcoholic fatty liver disease (ALD) in male mice. However, even when accounting for confounding factors such as absolute and relative alcohol intake, females are more sensitive to the effects of consumption compared to male mice. Therefore, the goal of this project was to determine whether CTRP3 prevented ALD in female mice. Methods: Female wild type (WT) and female CTRP3 transgenic over expressing (Tg) mice were fed an ethanol containing liquid …

The Effects Of Chronic Alcohol Consumption On The Mouse Endometrium, Sophia Fledderman

Undergraduate Honors Theses

As a result of alcohol consumption being highly prevalent in today’s society, research has been done to investigate the effects of alcohol on the body’s physiological systems. Research has indicated that heavy alcohol consumption is detrimental to the normal structure and function of some organs, especially the liver. However, little research has focused on the effects of chronic alcohol consumption on the female reproductive system. To investigate these effects, the uterine tissues of mice fed an ethanol diet (the NIAAA model also known as the Lieber-DeCarli diet) and mice fed a control diet were compared. The NIAAA model was chosen …

Gut Pathophysiology In Mouse Models Of Social Behavior Deficits, Kyla Scott

Undergraduate Honors Theses

Autism spectrum disorders (ASD) encompass neurodevelopment disorders characterized by atypical patterns of development that impact multiple areas of functioning beginning in early childhood. The etiology of ASD is unknown and there are currently no preventative treatment options. Gastrointestinal symptoms are commonly associated comorbidities. The microbiota-gut-brain axis is a multidirectional communication chain that connects the central and enteric nervous system that relates brain function to peripheral intestinal functions. Changes within this axis have been postulated in ASD. For example, the “leaky gut theory” proposes that chronic inflammation is linked to alterations in the bacterial profiles of the gut microbiome and subsequent …

The Influence Of Strength In Load-Velocity Relationships In The Back Squat, Thaddeus Light

Electronic Theses and Dissertations

Load-velocity relationships may vary between people of different strength levels and across different loads. The purpose of this dissertation was to investigate how external loads influence the velocity characteristics of the back squat exercise, and the influence of strength on these variables. Healthy male students with a history of resistance training completed repetitions at specified intensities of their estimated one-repetition maximum (1RM) until they reached 1RM. Back squat 3D motion analysis was captured using four Vicon T010 cameras (Vicon Motion Systems Ltd.; Oxford, UK) and Vicon Nexus 1.8.5 software. Data were transported into R custom coding statistical analysis software (version …

The Study Of Alcoholic Liver Diseases, Seun Emmanuel Owoseni

Electronic Theses and Dissertations

Excessive alcohol consumption is the primary contributing factor in the development of alcoholic liver diseases (ALD). Nicotine contained in tobacco is a major addictive alkaloid, which enhances the effects of ALDs. The major enzyme involved in nicotine metabolism is cytochrome P450 2A5 (CYP2A5) which is produced in the liver. Alcohol can stimulate the CYP2A5 enzyme. We utilized cyp2a5-/- knockout mice in this research to examine the effects of CYP2A5.

The cyp2a5-/- mice and wild-type (WT) mice were fed liquid ethanol diet with or without nicotine to induce ALD. Nicotine enhancing effects on ALD were observed in WT mice but not …

Success Rates Of Second Semester Anatomy Students In Online And On-Ground Classes At A Community College In East Tennessee, William Sproat

Electronic Theses and Dissertations

Educators expect the number of institutions offering online courses and the number of students enrolling in these courses to increase as many students, particularly nontraditional students, discover the advantages of online content delivery. Online courses require new methods of communication between students and faculty as well as discovering new ways to build relationships, earn student trust, conduct appropriate assessment, and deliver useful course content. Many institutions—public, private, and for-profit—offer a wide variety of online coursework but faculty, employers, and the public have expressed concerns about the quality of online course content. In particular, online delivery of coursework in the natural …

Immunodeficient R2g2 Mouse Strain Yields Spleens With Unusual Cytoarchitecture And Sympathetic Innervation, Nicholas Mason Britt, Madeleine Kate Miller, Donald B. Hoover Ph.D., John B. Schweitzer M.D.

Appalachian Student Research Forum

The nervous system and immune system contact one another through two-way communication in order to establish and preserve homeostasis. The sympathetic neurotransmitter norepinephrine has an impact on how the immune system responds by affecting regional blood flow and activation of adrenergic receptors on leukocytes. Former studies showed that immune cells are capable of releasing nerve growth factor allowing for the establishment and continuation of sympathetic nerves in targeted tissues. From this gathered information, it was hypothesized that sympathetic nerves would prove to be less frequent in spleens from the immunodeficient R2G2 mouse strain (Envigo) when compared to 129P3/J (129) and …

Effects Of Lower Extremity Aerobic Exercise And Conditioned Pain Modulation On Evoked Shoulder Pain, Logan Lumpkins, Craig Wassinger

Undergraduate Honors Theses

Background: Emerging evidence suggests that aerobic exercise and conditioned pain modulation may be advocated in treating patients with musculoskeletal pain. The effects of lower extremity aerobic exercise and conditioned pain modulation on evoked shoulder pain are not known.

Purpose: To determine the acute effects of lower extremity aerobic exercise and conditioned pain modulation on outcomes of evoked shoulder pain from pain pressure threshold measurements.

Study Design: Repeated measures.

Methods: Thirty (30) healthy volunteers were tested over the course of two sessions. Session 1 consisted of collecting pain pressure threshold measurements over the infraspinatus before and immediately following a conditioned pain …

Chat Expression In Chlamydia Muridarum-Infected Female Murine Genital Tract, Hallie Sartain

Undergraduate Honors Theses

Chlamydia trachomatis is the most prevalent agent of bacterial sexually transmitted infections in the world. However, a profuse number of cases are unreported, as the infection is often asymptomatic. Sequelae such as pelvic inflammatory disease, an increased risk of cervical cancer, premature birth, and perinatal infections in pregnant women can occur. Inflammation occurs in the body in response to infection or injury. Although inflammation can lead to some unwanted secondary effects, such as pain, it serves to return the body to homeostasis by restoring injured tissues and eliminating pathogens. One recently identified connection between the central nervous system and the …

In Vitro Investigation Of The Effect Of Exogenous Ubiquitin On Processes Associated With Atherosclerosis, Chase W. Mussard

Undergraduate Honors Theses

Atherosclerosis, characterized by the build-up of cholesterol, immune cells and cellular debris within arterial walls, is accelerated following myocardial infarction by poorly understood mechanisms. Ubiquitin, a small, well-studied intracellular protein involved in protein turnover via the proteasome pathway, has recently been shown to exert extracellular effects on cardiac myocytes, in vitro, and in mice undergoing myocardial remodeling. This study investigates the potential role of extracellular ubiquitin in atherosclerosis by determining its effects on two critical atherosclerotic processes: the migration of vascular smooth muscles cells and the uptake of modified LDL by monocyte/macrophages in foam cell formation. In the presence …

Role Of Ataxia Telangiectasia Mutated Kinase In The Healing Process Of The Heart Following Myocardial Infarction, Laura L. Daniel

Electronic Theses and Dissertations

Ataxia telangiectasia (AT), caused by mutations in the gene encoding ataxia telangiectasia mutated kinase (ATM), is a rare autosomal recessive disorder. AT individuals exhibit neuronal degeneration and are predisposed to cancer. Carriers of this disorder are predisposed to cancer and ischemic heart disease. Heart disease, mostly due to myocardial infarction (MI), is a leading cause of death in the US. Following MI, release of catecholamines in the heart stimulates β- adrenergic receptors (β-AR). Our lab has shown that β-AR stimulation increases ATM expression in the heart and myocytes, and ATM plays an important role in β-AR-stimulated myocardial remodeling with effects …

Characterization Of Murine Cardiac Cholinergic Innervation And Its Remodeling In Type 1 Diabetes., Abigail Marie Mabe

Electronic Theses and Dissertations

Murine models have become increasingly popular to study various aspects of cardiovascular diseases due to their ease of genetic manipulation. Unfortunately, there has been little effort put into describing the distribution of autonomic nerves in the mouse heart, making it difficult to compare current findings from clinical and experimental models related to cardiovascular diseases. Furthermore, determination of the requirements for the development of this system and its maintenance in adult mice remains largely unexplored. This study represents the first detailed mapping of cholinergic neuroanatomy of the mouse heart based on immunohistochemical staining using true cholinergic markers. We found cholinergic innervation …

In Vitro Assessment Of The Toxicity Of Cocaine And Its Metabolites In The Human Umbilical Artery, Tessa L. Long

Electronic Theses and Dissertations

An in vitro model was used to assess the effect of cocaine and its metabolites on the umbilical artery. Objectives were to pharmacologically confirm the presence of adrenergic innervation using tyramine, evaluate the ability of cocaine, benzoylecgonine, norcocaine and cocaethylene to potentiate vasoconstriction by serotonin and norepinephrine, examine the ability of ketanserin to block the enhanced vasoconstriction produced by cocaine, and determine displacement of 3 H-ketanserin by serotonin, norepinephrine, tyramine and mianserin. The vasoconstrictive effect of tyramine (100 μM) was enhanced in the presence of cocaine by 257%. Vasoconstrictive effects of serotonin and norepinephrine were significantly enhanced by cocaine by …

Quantal Mechanisms Underlying Stimulation-Induced Augmentation And Potentiation, Hong Cheng

Electronic Theses and Dissertations

Repetitive stimulation of motor nerves causes an increase in the number of packets of transmitter ("quanta") that can be released in the ensuing period. This represents a type of conditioning, in which synaptic transmission may be enhanced by prior activity. Despite many studies of this phenomenon, there have been no investigations of the quantal mechanisms underlying these events, due to the rapid changes in transmitter output and the short time periods involved. To examine this problem, a method was developed in which estimates of the quantal release parameters could be obtained over very brief periods (3 s). Conventional microelectrode techniques …

Gross And Histological Features Of A Myofascial Trigger Point In The Upper Trapezius, Kathryn E. Levee

Electronic Theses and Dissertations

The purpose of this study was to precisely locate, in living humans, a myofascial trigger point associated with the upper portion of the trapezius muscle (TrP1) that refers pain to the head and neck and to determine if this point is associated with anatomical structures. This study is descriptive and utilizes data from measurements of the location of TrP1 in relation to anatomical landmarks, of pressure sensitivity overlying the trigger point and electromyography recordings in localizing the trigger point. Information obtained from living humans was used to determine anatomical correlation to structures in cadavers. Results indicated there is little variability …

Microcirculation: Electrophysiological Basis For The Response Of Endothelial Cells To Inflammatory Mediators-Bradykinin, Kai Miao

Electronic Theses and Dissertations

Using conventional microelectrodes, I studied the electrical basis for determining the resting V$\sb{\rm m}$ in intact EC's from hamsters. The resting V$\sb{\rm m}$ were found to be $-$40 mV for aortic EC's and $-$43 mV for vena caval EC's. The contributions of ions to the resting V$\sb{\rm m}$ of aortic EC's were compared in terms of the transference number (t$\sb{\rm ion}$). To develop a technique for in situ monitoring changes in V$\sb{\rm m}$ of postcapillary venular EC's in the hamster mesentery, a voltage-sensitive fluorescent probe, bisoxonol, was used to load the cells and the fluorescence signals were analyzed under an …

Cytokines And Ovulation In The Mouse Ovary, Jong G. Kim

Electronic Theses and Dissertations

Ovulation has been hypothesized as an inflammatory process. Interleukin(IL)-1$\alpha$, IL-1$\beta$ and tumor necrosis factor(TNF)-$\alpha$ are potent cytokines produced from macrophages and various other cell types, and are pivotal components of inflammation. Although previous studies have investigated cytokine activities in the reproductive system, there is little information on their precise localization and activities during the periovulatory period. To investigate the role of cytokines in ovulation, experiments were designed to determine the immunohistochemical localization and time specific production of cytokines IL-1 and TNF-$\alpha$ using a mouse model at 36h, 12h, 6h, 2h before ovulation, and at 6h and 18h after ovulation in …

Denervation Supersensitivity Of The Rat Vas Deferens: A Role For Protein Kinase C, Sonny T. Abraham

Electronic Theses and Dissertations

A role for protein kinase C (PKC) in the denervation-induced supersensitivity of the rat vas deferens was investigated. Chronic, surgical denervation of the rat vas deferens (up to 8 days) resulted in tissues that produced enhanced contractile responses to norepinephrine (NE) in isolated organ baths. Single challenges of NE (10 $\mu$M) produced 0.6 $\pm$ 0.1 g of maximal tension in the control vas whereas in the paired, denervated tissue 2.2 $\pm$ 0.3 g of tension was recorded (n = 6). Cumulative concentration-effect curves to NE produced in the denervated vas deferens were shifted 18-fold to the left of the control …

Differential Role Of The Endothelium In Regulating Microvascular Blood Flow, Tao Tang

Electronic Theses and Dissertations

The vascular endothelial cell (EC) plays an important role in regulating vascular tone and local blood flow by sensing chemical and mechanical stimuli on the vascular wall and releasing a host of vasoactive substances upon activations of endogenous or exogenous vasoactive substances. The central hypothesis is that local control of blood now and autoregulatory behavior in the microcirculation is distinctive at different levels of the vasculature and is dependent on the cellular activities of the EC and its interaction with the local environment. The in vivo as well as the ex vivo, flow-controlled preparations of the hamster cheek pouch were …

Characterization Of The Vasoactivity Of Tachykinins In Isolated Rat Kidney: Functional Studies And In Vitro Receptor Autoradiography, Yuejin Chen

Electronic Theses and Dissertations

Although tachykinins have potent vascular actions, their effect on renal resistance blood vessels is currently unknown. The vasoactive properties of tachykinins and related analogs were assessed in isolated perfused rat kidney. At a basal perfusion pressure (PP) of 75 $\pm$ 6 mm Hg (n = 5), bolus injections of substance P (SP) had no significant vasoactive effect. Following a sustained increase in baseline PP (134 $\pm$ 10 mm Hg) produced by phenylephrine (1 $\mu$M), SP evoked a dose-dependent increase in PP. The largest dose of SP increased PP by 60 $\pm$ 5 mm Hg. The vasoconstrictor response to SP was …

Enhanced Renal Sympathetic And Cardiovascular Responses To Substance P In Hypertension, Gregory W. Lindsay

Electronic Theses and Dissertations

Blood pressure, heart rate, and renal sympathetic nerve responses were measured in 9-13 week old male spontaneously hypertensive rats (SHR) and compared to those in age and sex-matched Wistar-Kyoto (WKY) rats following intravenous injection of the neuropeptide substance P (SP), the nicotinic stimulant 1,1-dimethyl-4-phenylpiperazinium (DMPP), and the adrenoceptor stimulant norepinephrine (NE). Charles River Sprague-Dawley (CD) rats were used in some studies to develop methodologies. Measurements were made in control rats and also following sinoaortic denervation, pithing, ganglion blockade, or adrenoceptor blockade. Responses were evaluated in order to determine if ganglion stimulation by SP was enhanced in SHR compared to WKY …

Changes In Intracellular Chloride During Osmotic Stress And L-Alanine Uptake In Mouse Hepatocytes, Kening Wang

Electronic Theses and Dissertations

A stable intracellular ionic environment is necessary for hepatocytes to function normally. Thus, during hypotonic shock or L-alanine uptake, hepatocytes swell and then exhibit a regulatory volume decrease (RVD), which comprises an increase in K$\sp+$ conductance (G$\sb{\rm K}$), an increased K$\sp+$ efflux, and a hyperpolarization of transmembrane potential (V$\sb{\rm m}$). Since hepatocyte intracellular Cl$\sp-$ has been demonstrated to distribute passively with V$\sb{\rm m}$, this study is designed to test the hypothesis that the hypotonic shock- or L-alanine uptake-induced hyperpolarization of V$\sb{\rm m}$ might provide an electromotive force for the efflux of hepatocyte intracellular Cl$\sp-$, which in turn would contribute osmotically …

Electrophysiology, Cell Calcium, And Mechanisms Of Hepatocyte Volume Regulation, Walid E. Khalbuss

Electronic Theses and Dissertations

The electrophysiologic technique (Reuss, L., Proc. Natl. Acad. Sci. USA 82:6014, 1985) was modified to measure changes in steady-state hepatocyte volume during osmotic stress. Hepatocytes in mouse liver slices were loaded with tetramethylammonium ion (TMA$\sp{+}$) during transient exposure of cells to nystatin. Intracellular TMA$\sp{+}$ activity (a$\sp{\rm i}\sb{\rm TMA}$) was measured with TMA$\sp{+}$-sensitive, double-barreled microelectrodes. Loading hepatocytes with TMA$\sp{+}$ did not change their membrane potential (V$\sb{\rm m}$), and under steady-state conditions a$\sp{\rm i}\sb{\rm TMA}$ remained constant over 4 min in single impalements. Hyperosmotic solutions (50, 100, & 150 mM sucrose added to media) and hyposmotic solutions (sucrose in media reduced by …

Quantitation Of Teratogenic Effects Of 5-Fluorouracil Administered To Mice In Vivo Or In Submerged Limb Culture, Theresa A. Sanders

Electronic Theses and Dissertations

This study demonstrates the use of submerged limb culture in teratologic testing. Pregnant mice were treated on day 11 of gestation (E11, plug date = E0) with 10, 20 or 40 mg of 5-fluorouracil (FU) per kg body weight. On E17, treated and untreated fetuses were examined for gross malformations and were fixed in 95% ethanol. Reduction of limb size and digital defects, including ectrodactyly (ED), syndactyly (SD), microdactyly and polydactyly were dose-dependent. In parallel studies, pregnant mice were treated on the morning of E11 and embryos were removed either 7h (E11) or 24h (E12) later for submerged limb culture. …

Adaptation Of Striped Bass To Sea Water Following Direct Transfer From Freshwater: Morphological, Biochemical, And Physiological Parameters, Judy A. King

Electronic Theses and Dissertations

There has been heightened interest in the biology of striped bass (Morone saxatilis) because of increased pollution in their native spawning grounds and because of their extensive use in landlocked sport fisheries. Their euryhalinity makes them an excellent species for osmoregulation studies. The objective of this research was to study the rate of adaptation of striped bass gills to sea water (3% salt) after direct transfer from freshwater using biochemical (ion transport enzyme levels), physiological (chloride efflux), and ultrastructural methods. Striped bass have specialized osmoregulatory cells located on the interlamellar and afferent surfaces of their gill filaments as shown by …