Physiology Commons^™

Strong Inferences About Pain In Invertebrates Require Stronger Evidence, Edgar T. Walters

Animal Sentience

Evidence for sentience in animals distantly related to humans is often sought in observations of behavioral and neural responses to noxious stimuli that would be painful in humans. Most proposed criteria for painful sentience in “lower” animals such as decapod crustaceans have no necessary links to the affective (“suffering”) component of pain. The best evidence for painful affect in animals is learned aversion to stimuli associated with noxious experience, and conditioned preference for contexts associated with relief from aversive consequences of noxious experience, as expressed in voluntary behavior. Such evidence is currently lacking for any invertebrate except octopus.

Role Of Meibum And Tear Phospholipids In The Evaporative Water Loss Associated With Dry Eye., Samiyyah M. Sledge

Electronic Theses and Dissertations

It is generally believed that the tear film lipid surface film inhibits the rate of evaporation (Revap) of the underlying tear aqueous. It is also generally believed that changes in the composition of the tear film lipid layer is responsible for an increase in Revap in patients with dry eye. Both of these ideas have never been proven. The purpose of the current studies was to test these ideas. Revap was measured in vitro gravimetrically. Lipid spreading was measured using Raman spectroscopy and microscopy. The influence of the following surface films on the Revap of the sub phase of physiologically …

Race And Drug Toxicity: A Study Of Three Cardiovascular Drugs With Strong Pharmacogenetic Recommendations., Travis J. O'Brien, Kevin Fenton, Alfateh Sidahmed, April Barbour, Arthur F Harralson

Pharmacology and Physiology Faculty Publications

No abstract provided.

The Role Of Nutrition And Hormone Signaling In Extended Larval Development And Obesity In Starvation-Selected Drosophila Melanogaster, Jennifer M. Clark

UNLV Theses, Dissertations, Professional Papers, and Capstones

Brief periods of starvation are a common stressor that most animals encounter in the wild and must be able to survive in order to maximize their fitness. Starvation resistance of the adult fruit fly, Drosophila melanogaster, is thought to be primarily conferred by adult fat stores, body size, metabolic rate, behavior, and activity levels. Additionally, flies selected for starvation resistance also often show delayed pupariation, which is usually indicative of altered hormone signaling. How starvation selection extends development and if it contributes to adult starvation resistance remains incompletely studied. Identifying the targets of starvation selection that cause extended development and …

Neurogenic Hypertension Mediated Mitochondrial Abnormality Leads To Cardiomyopathy: Contribution Of Upr Mt And Norepinephrine-Mir- 18a-5p-Hif-1Α Axis, Shyam Sundar Nandi, Kenichi Katsurada, Sushil K. Mahata, Kaushik K. Patel

Journal Articles: Cellular & Integrative Physiology

Aims: Hypertension increases the risk of heart disease. Hallmark features of hypertensive heart disease is sympathoexcitation and cardiac mitochondrial abnormality. However, the molecular mechanisms for specifically neurally mediated mitochondrial abnormality and subsequent cardiac dysfunction are unclear. We hypothesized that enhanced sympatho-excitation to the heart elicits cardiac miR-18a-5p/HIF-1α and mitochondrial unfolded protein response (UPR^mt) signaling that lead to mitochondrial abnormalities and consequent pathological cardiac remodeling. Methods and Results: Using a model of neurogenic hypertension (NG-HTN), induced by intracerebroventricular (ICV) infusion of Ang II (NG-HTN; 20 ng/min, 14 days, 0.5 μl/h, or Saline; Control, 0.9%) through osmotic mini-pumps in Sprague-Dawley …

Novel Mammalian Models For Understanding And Treating Spinal Cord Injury, Michael B. Orr

Theses and Dissertations--Physiology

Spinal cord injury (SCI) is devastating and often leaves the injured individual with persistent dysfunction. The injury persists because humans have poor wound repair and there are no pharmacologic treatments to induce wound repair after SCI. The continued efforts to discover therapeutic targets and develop treatments heavily relies on animal models. The purpose of this project is to develop and study novel mammalian models of SCI to provide insights for the development and effective implementation of SCI therapies.

Lab mice (Mus musculus) are a powerful tool for recapitulating the progression and persistent damage evident in human SCI, but …

Neutrophil Signaling During Myocardial Infarction Wound Repair, Michael J. Daseke, Upendra Chalise, Mediha Becirovic-Agic, Jeffrey D. Salomon, Leah M. Cook, Adam J. Case, Merry L. Lindsey

Journal Articles: Cellular & Integrative Physiology

Neutrophils are key effector cells of the innate immune system, serving as a first line of defense in the response to injury and playing essential roles in the wound healing process. Following myocardial infarction (MI), neutrophils infiltrate into the infarct region to propagate inflammation and begin the initial phase of cardiac wound repair. Pro-inflammatory neutrophils release proteases to degrade extracellular matrix (ECM), a necessary step for the removal of necrotic myocytes as a prelude for scar formation. Neutrophils transition their phenotype over time to regulate MI inflammation resolution and stabilize scar formation. Neutrophils contribute to the evolution from inflammation to …

The Role Of Central Ace2 And Nrf2 In Sympatho-Excitation: Responses To Central Angiotensin Ii, Anyun Ma

Theses & Dissertations

Sympatho-excitation is a key characteristic in cardiovascular diseases such as chronic heart failure (CHF) and primary Hypertension (HTN). Evidence suggests that increased sympathetic tone is closely related to activation of the Renin-Angiotensin-Aldosterone system (RAAS) in the central nervous system. An underlying mechanism for sympatho-excitation is thought to be oxidative stress resulting from Angiotensin II (AngII) type 1 receptor (AT1R) activation. Over the past several decades, pharmacological targeting of components of the RAAS have been used as standard therapy in CHF and HTN. However, additional therapeutic strategies are necessary to control these diseases. Oxidative stress is regulated, in part, by the …

Alternative Polyadenylation Modulates Expression Of Pro-Fibrotic Proteins And Contributes To Lung Fibrosis, Junsuk Ko

Dissertations and Theses (Open Access)

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease which affects about 5 to 8 million individuals in the world. Despite the high prevalence, there is currently no cure for IPF, and the cause of this disease is still unclear. Our laboratory and collaborators have shown that nudix hydrolase 21 (NUDT21, which is also known as cleavage factor 25, CFIm25) is a key regulator of alternative polyadenylation (APA). NUDT21 depletion causes 3’UTR shortening via APA leading to enhanced mRNA stability and protein translation. This NUDT21 reduction promotes tumor growth in glioblastoma by enhancing expression of oncogenes. Cancer and IPF share …

Utilizing Breathing Techniques To Maximize Training Performance, Peyton Cater

UNLV Theses, Dissertations, Professional Papers, and Capstones

Anaerobic exercise causes metabolic acidosis to occur in the muscle, which is unfavorable for sustaining high intensity activity, as fatigue starts to set in. In order to compensate for the onset of fatigue produced by an acidic environment, respiratory alkalosis, induced by hyperventilation, can be performed to mitigate these effects. In contrast, research has shown that slowing down the breath rate, such as a two second inhale and three second exhale, has led to an increase in performance outcomes. Purpose: To investigate power output and the physiological responses after implementation of different breathing techniques during the recovery periods of intermittent …

Rapid Evolution Of Starvation Resistance In Drosophila: Physiological And Molecular Mechanisms, Austin Joseph Mckenna

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Gibbs lab has maintained starvation-selected Drosophila melanogaster for >130 generations. These starvation-selected flies evolved an obese phenotype with a suite of physiological differences compared to control-fed flies. Previous studies have shown that long-term starvation-selected Drosophila contain more lipids, have lower metabolic rates and develop more slowly than controls. This dissertation encompasses 1) Examining the molecular mechanisms contributing to starvation resistance, 2) Functional validation of the candidate plin1 allele, and 3) Rapid physiological and genomic evolution in starvation-selected Drosophila.

Starvation-selected Drosophila survive starvation conditions much longer than control-fed flies. This study took a simple approach to identify possible differences in …

Nanoformulation Of The Superoxide Dismutase Mimic, Mntnbuoe-2-Pyp5+, Prevents Its Acute Hypotensive Response, Sarah L. Schlichte, Svetlana Romanova, Kenichi Katsurada, Elizabeth A. Kosmacek, Tatiana K. Bronich, Kaushik K. Patel, Rebecca E. Oberley-Deegan, Matthew C. Zimmerman

Journal Articles: Cellular & Integrative Physiology

Scavenging superoxide (O₂^•-) via overexpression of superoxide dismutase (SOD) or administration of SOD mimics improves outcomes in multiple experimental models of human disease including cardiovascular disease, neurodegeneration, and cancer. While few SOD mimics have transitioned to clinical trials, MnTnBuOE-2-PyP⁵⁺ (BuOE), a manganese porphyrin SOD mimic, is currently in clinical trials as a radioprotector for cancer patients; thus, providing hope for the use of SOD mimics in the clinical setting. However, BuOE transiently alters cardiovascular function including a significant and precipitous decrease in blood pressure. To limit BuOE's acute hypotensive action, we developed a mesoporous silica nanoparticle …

Seen In Science: Lgbtq+ Inclusivity In Anatomy & Physiology Texts, Harshini Sirvisetty, Kat Ray King, Linda Catherine Fuselier

Undergraduate Arts and Research Showcase

Biology is unique from other science disciplines in that concepts taught in core classes can inform our student’s understanding of sex and gender. A biology major encounters lessons on sex determination, sexual reproduction, and sex characteristics in their courses. The language used in these units matters. It is imperative that educators consider how the language, examples, and content that we use in classrooms drive (or not) inclusivity for gender- and sexuality-diverse (GSD) (aka LGBTQ+) individuals. We chose to analyze four college-level human anatomy/physiology (AP) textbooks for GSD population inclusivity. We adopted a queer theory framework to critically examine how sex, …

Glp-1 Mediated Diuresis And Natriuresis Are Blunted In Heart Failure And Restored By Selective Afferent Renal Denervation, Kenichi Katsurada, Shyam Sundar Nandi, Hong Zheng, Xuefei Liu, Neeru M. Sharma, Kaushik K. Patel

Journal Articles: Cellular & Integrative Physiology

BACKGROUND: Glucagon-like peptide-1 (GLP-1) induces diuresis and natriuresis. Previously we have shown that GLP-1 activates afferent renal nerve to increase efferent renal sympathetic nerve activity that negates the diuresis and natriuresis as a negative feedback mechanism in normal rats. However, renal effects of GLP-1 in heart failure (HF) has not been elucidated. The present study was designed to assess GLP-1-induced diuresis and natriuresis in rats with HF and its interactions with renal nerve activity.

METHODS: HF was induced in rats by coronary artery ligation. The direct recording of afferent renal nerve activity (ARNA) with intrapelvic injection of GLP-1 and total …

An Identification Of Tgf-B'S Role In Ischemic Cholangiopathy, Courtney Chmielewski

Theses and Dissertations

Organ transplants are a necessary intervention for many diseases that result in end stage organ failure. The donation pool cannot match the demands of the transplant list, so expanding the pool to include donation after cardiac death (DCD) is desired. However, there are increased odds of graft failure and ischemic cholangiopathy leading to inferior outcomes when DCD livers are used. Ischemic cholangiopathy consists of multiple diffuse strictures and fibrosis of the bile ducts leading to a loss of epithelialization and fibrosis. The cellular mechanism is proposed to be epithelial-to-mesenchymal transition (EMT). TGF-�� is seen as a key initiator of EMT, …

Connectivity Differences Between Gulf War Illness (Gwi) Phenotypes During A Test Of Attention, Tomas Clarke, Jessie Jamieson, Patrick Malone, Rakib U. Rayhan, Stuart Washington, John W. Vanmeter, James N. Baraniuk

Department of Mathematics: Faculty Publications

One quarter of veterans returning from the 1990–1991 Persian Gulf War have developed Gulf War Illness (GWI) with chronic pain, fatigue, cognitive and gastrointestinal dysfunction. Exertion leads to characteristic, delayed onset exacerbations that are not relieved by sleep. We have modeled exertional exhaustion by comparing magnetic resonance images from before and after submaximal exercise. One third of the 27 GWI participants had brain stem atrophy and developed postural tachycardia after exercise (START: Stress Test Activated Reversible Tachycardia). The remainder activated basal ganglia and anterior insulae during a cognitive task (STOPP: Stress Test Originated Phantom Perception). Here, the role of attention …

Trade-Offs Between Survival And Reproduction In Starvation-Selected Drosophila Melanogaster, Tammara Beeghly

UNLV Theses, Dissertations, Professional Papers, and Capstones

Evolutionary outcomes are demonstrated by traits that affect an organism’s schedule of reproduction and survival. These life history traits are reflected in an organism’s physiology, development and behavior. Environmental changes, such as availability of nutritional resources, can profoundly affect evolutionary outcomes of individuals and populations. When shortages arise, there will be trade-offs in the allocation of resources, where one trait prevails at the expense of another.

In the laboratory, we can mimic conditions in nature and study the specific effects of the conditions that we re-create. In our case, over 100 generations of Drosophila melanogaster have been selected for starvation …

Redox Biology In Physiology And Disease, Matthew C. Zimmerman, Adam J. Case

Journal Articles: Cellular & Integrative Physiology

No abstract provided.

Redox-Sensitive Calcium/Calmodulin-Dependent Protein Kinase Iiα In Angiotensin Ii Intra-Neuronal Signaling And Hypertension, Urmi Basu, Adam J. Case, Jinxu Liu, Jun Tian, Yulong Li, Matthew C. Zimmerman

Journal Articles: Cellular & Integrative Physiology

Dysregulation of brain angiotensin II (AngII) signaling results in modulation of neuronal ion channel activity, an increase in neuronal firing, enhanced sympathoexcitation, and subsequently elevated blood pressure. Studies over the past two decades have shown that these AngII responses are mediated, in part, by reactive oxygen species (ROS). However, the redox-sensitive target(s) that are directly acted upon by these ROS to execute the AngII pathophysiological responses in neurons remain unclear. Calcium/calmodulin-dependent protein kinase II (CaMKII) is an AngII-activated intra-neuronal signaling protein, which has been suggested to be redox sensitive as overexpressing the antioxidant enzyme superoxide dismutase attenuates AngII-induced activation of …

Central Glucagon-Like Peptide-1 Receptor Signaling Via Brainstem Catecholamine Neurons Counteracts Hypertension In Spontaneously Hypertensive Rats, Kenichi Katsurada, Masanori Nakata, Toshinobu Saito, Boyang Zhang, Yuko Maejima, Shyam Sundar Nandi, Neeru M. Sharma, Kaushik K. Patel, Kazuomi Kario, Toshihiko Yada

Journal Articles: Cellular & Integrative Physiology

Glucagon-like peptide-1 receptor (GLP-1R) agonists, widely used to treat type 2 diabetes, reduce blood pressure (BP) in hypertensive patients. Whether this action involves central mechanisms is unknown. We here report that repeated lateral ventricular (LV) injection of GLP-1R agonist, liraglutide, once daily for 15 days counteracted the development of hypertension in spontaneously hypertensive rats (SHR). In parallel, it suppressed urinary norepinephrine excretion, and induced c-Fos expressions in the area postrema (AP) and nucleus tractus solitarius (NTS) of brainstem including the NTS neurons immunoreactive to dopamine beta-hydroxylase (DBH). Acute administration of liraglutide into fourth ventricle, the area with easy access to …

Autonomic And Redox Imbalance Correlates With T-Lymphocyte Inflammation In A Model Of Chronic Social Defeat Stress, Cassandra M. Moshfegh, Safwan K. Elkhatib, Christopher W. Collins, Allison J. Kohl, Adam J. Case

Journal Articles: Cellular & Integrative Physiology

Patients diagnosed with post-traumatic stress disorder (PTSD) are at a significantly elevated risk of developing comorbid inflammatory conditions, but the mechanisms underlying this predilection remain unclear. Our previous work has shown that T-lymphocytes exposed to elevated levels of norepinephrine (NE) displayed a pro-inflammatory signature reminiscent of an autoreactive phenotype. With this, we hypothesized that the increased sympathetic tone observed during psychological trauma may be promoting pro-inflammatory T-lymphocytes, which causes a predisposition to comorbid inflammatory conditions. Here, we examined the consequences of psychological trauma on splenic T-lymphocytes using a mouse model of repeated social defeat stress. Social defeat led to anxiety-like …

Spinal Control Of Locomotion: Individual Neurons, Their Circuits And Functions, Marie-Pascale Côté, Lynda M. Murray, Maria Knikou

Publications and Research

Systematic research on the physiological and anatomical characteristics of spinal cord interneurons along with their functional output has evolved for more than one century. Despite significant progress in our understanding of these networks and their role in generating and modulating movement, it has remained a challenge to elucidate the properties of the locomotor rhythm across species. Neurophysiological experimental evidence indicates similarities in the function of interneurons mediating afferent information regarding muscle stretch and loading, being affected by motor axon collaterals and those mediating presynaptic inhibition in animals and humans when their function is assessed at rest. However, significantly different muscle …

Systematic Pan-Cancer Analysis Of Somatic Allele Frequency., Liam Spurr, Muzi Li, Nawaf Alomran, Qianqian Zhang, Paula Restrepo, Mercedeh Movassagh, Chris Trenkov, Nerissa Tunnessen, Tatiyana Apanasovich, Keith A Crandall, Nathan Edwards, Anelia Horvath

Pharmacology and Physiology Faculty Publications

Imbalanced expression of somatic alleles in cancer can suggest functional and selective features, and can therefore indicate possible driving potential of the underlying genetic variants. To explore the correlation between allele frequency of somatic variants and total gene expression of their harboring gene, we used the unique data set of matched tumor and normal RNA and DNA sequencing data of 5523 distinct single nucleotide variants in 381 individuals across 10 cancer types obtained from The Cancer Genome Atlas (TCGA). We analyzed the allele frequency in the context of the variant and gene functional features and linked it with changes in …

Effect Of Exercise And Hypoxia On Plasma Telomerase, Charli D. Aguilar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: Telomerase reverse transcriptase (TERT) is the enzyme that adds telomeric sequences to the end of linear chromosomes. Exercise has shown to upregulate acutely leukocyte TERT after just 30 minutes of running on a treadmill at 80% of VO2max (Denham et al., 2016). Hypoxia inducible factor 1 (HIF-1) is also a mediator of TERT in in vitro (Nishi et al., 2004). Moderate acute exposure to hypoxia was associated with substantial increases in plasma TERT in a recent study on rats (Wang et al., 2014). The specific aim of the current study was to identify if acute hypoxia upregulates plasma TERT …

Disruption Of Neonatal Cardiomyocyte Physiology Following Exposure To Bisphenol-A., Manelle Ramadan, Meredith Sherman, Rafael Jaimes, Ashika Chaluvadi, Luther Swift, Nikki Gillum Posnack

Pharmacology and Physiology Faculty Publications

Bisphenol chemicals are commonly used in the manufacturing of polycarbonate plastics, polyvinyl chloride plastics, resins, and thermal printing applications. Humans are inadvertently exposed to bisphenols through contact with consumer products and/or medical devices. Recent reports have shown a link between bisphenol-a (BPA) exposure and adverse cardiovascular outcomes; although these studies have been limited to adult subjects and models. Since cardiac physiology differs significantly between the developing and adult heart, we aimed to assess the impact of BPA exposure on cardiac function, using a neonatal cardiomyocyte model. Neonatal rat ventricular myocytes were monitored to assess cell viability, spontaneous beating rate, beat …

Developing Novel Therapeutics For Bacterial Lung Infections, Brandon J. Baer, Ruud Veldhuizen, Cory Yamashita

Western Research Forum

Background: Bacterial lung infections are leading causes of death worldwide. Unfortunately, increasing resistance to antibiotics and the inflammation often accompanying these infections are leading to poor outcomes despite antibiotic intervention. Complicating treatment further, the tree-like branching structure of the lung makes drug delivery to distal sites of infection difficult. Our research aims to address these challenges by developing new therapeutics and new tools to improve and assess drug delivery, bacterial killing and inflammation. Our therapy combines host defense peptides, which have been shown to kill antibiotic-resistant bacteria and down regulate inflammation, with a pulmonary vehicle, exogenous surfactant, that can improve …

Loss Of The Intellectual Disability And Autism Gene Cc2d1a And Its Homolog Cc2d1b Differentially Affect Spatial Memory, Anxiety, And Hyperactivity, Marta Zamarbide, Adam Oaks, Heather Pond, Julia Adelman, M. Chiara Manzini

Pharmacology and Physiology Faculty Publications

Hundreds of genes are mutated in non-syndromic intellectual disability (ID) and autism spectrum disorder (ASD), with each gene often involved in only a handful of cases. Such heterogeneity can be daunting, but rare recessive loss of function (LOF) mutations can be a good starting point to provide insight into the mechanisms of neurodevelopmental disease. Biallelic LOF mutations in the signaling scaffold CC2D1Acause a rare form of autosomal recessive ID, sometimes associated with ASD and seizures. In parallel, we recently reported that Cc2d1a-deficient mice present with cognitive and social deficits, hyperactivity and anxiety. In Drosophila, loss of the only …

Optimization Of Wavelength Selection For Multispectral Image Acquisition: A Case Study Of Atrial Ablation Lesions, Huda Asfour, S. Guan, Narine Muselimyan, Luther M. Swift, Murray Loew, Narine Sarvazyan

Pharmacology and Physiology Faculty Publications

In vivo autofluorescence hyperspectral imaging of moving objects can be challenging due to motion artifacts and to the limited amount of acquired photons. To address both limitations, we selectively reduced the number of spectral bands while maintaining accurate target identification. Several downsampling approaches were applied to data obtained from the atrial tissue of adult pigs with sites of radiofrequency ablation lesions. Standard image qualifiers such as the mean square error, the peak signal-to-noise ratio, the structural similarity index map, and an accuracy index of lesion component images were used to quantify the effects of spectral binning, an increased spectral distance …

Sympatho-Excitatory Response To Pulmonary Chemosensitive Spinal Afferent Activation In Anesthetized, Vagotomized Rats, Julia A. Shanks, Zhiqiu Xia, Steven J. Lisco, George J. Rozanski, Harold D. Schultz, Irving H. Zucker, Han-Jun Wang

Journal Articles: Cellular & Integrative Physiology

The sensory innervation of the lung is well known to be innervated by nerve fibers of both vagal and sympathetic origin. Although the vagal afferent innervation of the lung has been well characterized, less is known about physiological effects mediated by spinal sympathetic afferent fibers. We hypothesized that activation of sympathetic spinal afferent nerve fibers of the lung would result in an excitatory pressor reflex, similar to that previously characterized in the heart. In this study, we evaluated changes in renal sympathetic nerve activity (RSNA) and hemodynamics in response to activation of TRPV1-sensitive pulmonary spinal sensory fibers by agonist application …

Rhythm: An Open Source Imaging Toolkit For Cardiac Panoramic Optical Mapping, Christopher Gloschat, Kedar Aras, Shubnam Gupta, N. Rokhana Faye, Hanyu Zhang, Matthew W. Kay, Igor R Efimov, +Several Additional Authors

Pharmacology and Physiology Faculty Publications

Fluorescence optical imaging techniques have revolutionized the field of cardiac electrophysiology and advanced our understanding of complex electrical activities such as arrhythmias. However, traditional monocular optical mapping systems, despite having high spatial resolution, are restricted to a two-dimensional (2D) field of view. Consequently, tracking complex three-dimensional (3D) electrical waves such as during ventricular fibrillation is challenging as the waves rapidly move in and out of the field of view. This problem has been solved by panoramic imaging which uses multiple cameras to measure the electrical activity from the entire epicardial surface. However, the diverse engineering skill set and substantial resource …