Systems and Integrative Physiology Commons^™

The Effect Of Cellular Dehydration On Glucose Regulation In Lean And Obese Females, Chunbo Yang

Graduate Theses and Dissertations

A chronically elevated vasopressin level has been associated with an impaired glucose regulation system in humans. A recent study in patients with diabetes suggested that low water intake is associated with impaired glucose regulation. The aim of this study was to examine the effect of hypertonic saline infusion on glucose regulation in healthy females. Thirty healthy, non-diabetic females performed a 2-h infusion followed by a 4-h oral glucose tolerance test (OGTT). Every subject participated in two trials separated by one month, in a counterbalanced order. Two trials were identical in the procedure, differing in the concentration of saline infusion, with …

Effects Of A Form Of Equine-Facilitated Learning On Heart Rate Variability, Immune Function, And Self-Esteem In Older Adults, Ann L. Baldwin, Barbara K. Rector, Ann C. Alden

People and Animals: The International Journal of Research and Practice

Equine-facilitated learning (EFL) helps people access their immediate sensations and feelings because horses, as prey animals, are continually aware of their environment and provide instant feedback to human behaviors and emotions. We hypothesize that during EFL, older people become more aware of their bodily sensations and emotions, leading to increased heart rate variability (HRV), improved self-esteem (Rosenberg scale), and improved immune function. Twenty-four subjects (age > 55) participated in a single 15-minute EFL activity, Con Su Permiso, during which they focused on their bodily sensations and the responses of the horse as they moved toward and around the horse. Subjects …

Thermoregulatory Adaptations Following Sprint Interval Training, Jonathan E. Wingo, Charlie P. Katica, Svetlana Nepocatych, Andrew T. Del Pozzi, Greg A. Ryan

Journal of Human Performance in Extreme Environments

Traditional endurance training typically involves weeks of long-duration (60–90 min) exercise performed at a moderate to vigorous intensity. An alternative paradigm, sprint interval training, is characterized by multiple bouts of short-duration, high-intensity exercise. Similar fitness benefits from the two paradigms have been demonstrated, but whether sprint interval training—like traditional endurance training—induces heat acclimation remains unclear.

Purpose

To test the hypothesis that sprint interval training performed over six sessions results in measureable thermoregulatory and cardiovascular adaptations consistent with heat acclimation.

Methods

Seven untrained men [mean ± SD, 13 ± 5% body fat, 22 ± 3 y, 3.1 ± 0.3 L/min peak …

The Mechanism Of Biotremor Production In The Veiled Chameleon (Chamaeleo Calyptratus), Samuel Tegge

Masters Theses & Specialist Projects

Vibratory communication has evolved in numerous animal groups, including insects, spiders, fishes, mammals, and was recently discovered in veiled chameleons (Chamaeleo calyptratus). I examined the mechanism by which C. calyptratus produce these biotremors. Muscle activity data were gathered during simulated anti-predator responses via electromyography (EMG) with simultaneous recordings of biotremor production using an accelerometer. I correlated EMG data with the accelerometer data to implicate the muscles responsible for the production of the biotremors. Mixed-effect linear regression models described the mechanism, and a model selection framework determined which model fit the data best. I then used an analysis of variance to …

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 …

Environmental Effects On Drosophila Brain Development And Learning, Xia Wang, Amei Amei, J. Steven De Belle, Stephen P. Roberts

Biological Sciences Faculty Research & Creative Works

Brain development and behavior are sensitive to a variety of environmental influences including social interactions and physicochemical stressors. Sensory input in situ is a mosaic of both enrichment and stress, yet little is known about how multiple environmental factors interact to affect brain anatomical structures, circuits and cognitive function. In this study, we addressed these issues by testing the individual and combined effects of sub-adult thermal stress, larval density and early-adult living spatial enrichment on brain anatomy and olfactory associative learning in adult Drosophila melanogaster. In response to heat stress, the mushroom bodies (MBs) were the most volumetrically impaired among …

Can A Comprehensive Transition Plan To Barefoot Running Be The Solution To The Injury Epidemic In American Endurance Runners?, Michael A. Scarlett

CMC Senior Theses

Fossils belonging to the genus Homo, dating as far back as two million years ago, exhibit uniquely efficient features suggesting that early humans had evolved to become exceptional endurance runners. Although they did not have the cushion or stability-control features provided in our modern day running shoes, our early human ancestors experienced far less of the running-related injuries we experience today. The injury rate has been estimated as high as 90% annually for Americans training for a marathon and as high as 79% annually for all American endurance runners. There is an injury epidemic in conventionally shod populations that …

Direct Conversion Of Mouse Astrocytes Into Neural Progenitor Cells And Specific Lineages Of Neurons, Kangmu Ma, Xiaobei Deng, Xiaohuan Xia, Zhaohuan Fan, Xinrui Qi, Yongxiang Wang, Yuju Li, Yizhao Ma, Qiang Chen, Hui Peng, Jianqing Ding, Chunhong Li, Yunlong Huang, Changhai Tian, Jialin C. Zheng

Journal Articles: Cellular & Integrative Physiology

Background: Cell replacement therapy has been envisioned as a promising treatment for neurodegenerative diseases. Due to the ethical concerns of ESCs-derived neural progenitor cells (NPCs) and tumorigenic potential of iPSCs, reprogramming of somatic cells directly into multipotent NPCs has emerged as a preferred approach for cell transplantation.

Methods: Mouse astrocytes were reprogrammed into NPCs by the overexpression of transcription factors (TFs) Foxg1, Sox2, and Brn2. The generation of subtypes of neurons was directed by the force expression of cell-type specific TFs Lhx8 or Foxa2/Lmx1a.

Results: Astrocyte-derived induced NPCs (AiNPCs) share high similarities, including the expression of NPC-specific genes, DNA methylation …

Novel Antioxidant Properties Of Doxycycline, Dahn L. Clemens, Michael J. Duryee, Cleofes Sarmiento, Andrew Chiou, Jacob D. Mcgowan, Carlos D. Hunter, Sarah L. Schlichte, Jun Tian, Lynell W. Klassen, James R. O'Dell, Geoffrey M. Thiele, Ted R. Mikuls, Matthew C. Zimmerman, Daniel R. Anderson

Journal Articles: Cellular & Integrative Physiology

Doxycycline (DOX), a derivative of tetracycline, is a broad-spectrum antibiotic that exhibits a number of therapeutic activities in addition to its antibacterial properties. For example, DOX has been used in the management of a number of diseases characterized by chronic inflammation. One potential mechanism by which DOX inhibits the progression of these diseases is by reducing oxidative stress, thereby inhibiting subsequent lipid peroxidation and inflammatory responses. Herein, we tested the hypothesis that DOX directly scavenges reactive oxygen species (ROS) and inhibits the formation of redox-mediated malondialdehyde-acetaldehyde (MAA) protein adducts. Using a cell-free system, we demonstrated that DOX scavenged reactive oxygen …

Space Operations In The Suborbital Space Flight Simulator And Mission Control Center: Lessons Learned With Xcor Lynx, Pedro Llanos, Christopher Nguyen, David Williams, Kim O. Chambers, Erik Seedhouse, Robert Davidson

Journal of Aviation/Aerospace Education & Research

This study was conducted to better understand the performance of the XCOR Lynx vehicle. Because the Lynx development was halted, the best knowledge of vehicle dynamics can only be found through simulator flights. X-Plane 10 was chosen for its robust applications and accurate portrayal of dynamics on a vehicle in flight. The Suborbital Space Flight Simulator (SSFS) and Mission Control Center (MCC) were brought to the Applied Aviation Sciences department in fall 2015 at Embry-Riddle Aeronautical University, Daytona Beach campus. This academic and research tool is a department asset capable of providing multiple fields of data about suborbital simulated flights. …

S-Nitrosation Of Protein Phosphatase 1 Mediates Alcohol-Induced Ciliary Dysfunction, Michael E. Price, Adam J. Case, Jacqueline A. Pavlik, Jane M. Devasure, Todd A. Wyatt, Matthew C. Zimmerman, Joseph H. Sisson

Journal Articles: Cellular & Integrative Physiology

Alcohol use disorder (AUD) is a strong risk factor for development and mortality of pneumonia. Mucociliary clearance, a key innate defense against pneumonia, is perturbed by alcohol use. Specifically, ciliated airway cells lose the ability to increase ciliary beat frequency (CBF) to β-agonist stimulation after prolonged alcohol exposure. We previously found that alcohol activates protein phosphatase 1 (PP1) through a redox mechanism to cause ciliary dysfunction. Therefore, we hypothesized that PP1 activity is enhanced by alcohol exposure through an S-nitrosothiol-dependent mechanism resulting in desensitization of CBF stimulation. Bronchoalveolar S-nitrosothiol (SNO) content and tracheal PP1 activity was increased in wild-type (WT) …

Environmental And Physiological Regulation Of Yellow Stingray Color Change, Theresa Rose Gunn

College of Graduate Studies: Theses & Dissertations

Many reef fishes exhibit dynamic coloration and body patterns that can change under nervous or hormonal control. Several species of benthic sharks and rays likely alter melanin in the skin to provide background matching for camouflage. The yellow stingray (Urobatis jamaicensis) is a benthically-oriented elasmobranch with elaborate spot patterns that provide effective camouflage within its habitats. This patterning, when coupled with the ability to alter melanin in response to background color, could increase background matching effectiveness in these species. The yellow stingray has been anecdotally noted to lighten or darken skin color.However, it is unclear whether this type …

Cold Tolerance, Diapause And Winter Survival Of The Brown Marmorated Stink Bug (Halyomorpha Halys), Naomi Sibayan

All Master's Theses

The brown marmorated stink bug, Halyomorpha halys, is native to eastern Asia and is an invasive pest in the United States. Limited research has been done regarding the factors influencing this species’ winter survival within invaded northern regions. Cold tolerance has been previously evaluated in the eastern United States, bot nut within western populations. Winter diapause. Along with any potential links between diapause and cold tolerance remain unstudied. I examined characteristics of cold tolerance, diapause and overwintering sites to evaluate the factors contributing to the winter survival and, ultimately, persistence of this pest within central Washington. This study measured seasonal …

Impact Of Temperature Increase On Freshwater Fish Species: Energetics And Muscle Mechanics Of Two Centrarchids, Israt Jahan

Masters Theses

Fishes have evolved physiologically to live within a specific range of environmental variation and existence outside of that range can be stressful or fatal. These ranges can coincide for fishes that evolved in similar habitats. This study investigates physiological processes limiting thermal tolerance, specifically how changes in water temperature affect the swimming energetics and muscle mechanics in largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrochirus). I focused on the impact of temperature change at the muscle level in these two species and the capacity to adapt to rapid changes in the environment. Fish were housed at …

Branched Short Chain Fatty Acid Isovaleric Acid Causes Smooth Muscle Relaxation Via Camp/Pka Pathway, Inhibits Gastrointestinal Motility, And Disrupts Peristaltic Movement, Bryan Adam Blakeney

Theses and Dissertations

Isovaleric Acid (IVA) is a 5-carbon branched chain fatty acid present in fermented foods and produced by the fermentation of leucine by colonic bacteria. IVA activates G-protein coupled receptors such as FFAR2, FFAR3, and OR51E1 known to be expressed on enteric neurons and enteroendocrine cells. We previously reported that the shorter, straight chain fatty acids acetate, propionate and butyrate, differentially affect colonic propulsion; however, the effect of branched chain fatty acids on gastrointestinal motility is unknown. We hypothesize that IVA relaxes smooth muscle in a cAMP/PKA dependent manner by direct action on smooth muscle cells. IVA will also decrease peristalsis …

Organizational Effects Of Defeminizing Toxicants: Lessons Learned From An Environmental Sentinel Organism, The Fathead Minnow., Jonathan Ali

Theses & Dissertations

Endocrine disrupting compounds (EDCs) are chemicals that interfere with hormone function and are increasingly detected in aquatic environments, where they elicit adverse effects from exposed organisms. The toxicological effects of EDCs can be described as either activational (reversible) or organizational (irreversible), where the latter are associated with adverse outcomes in reproductive performance of adult fish. However, few studies have investigated the organizational impacts of anti-estrogenic or “defeminizing” EDCs, e.g. agrichemicals or pharmacological agents, in an environmentally-relevant or “sentinel” species. The objective of this study was to investigate the impacts of early-life EDC-initiated changes in estrogenic gene expression on organizational effects …

Insights Into The Therapeutic Potential Of Salt Inducible Kinase 1: A Novel Mechanism Of Metabolic Control, Randi Fitzgibbon

Dissertations and Theses (Open Access)

Salt inducible kinase 1 (SIK1) has been considered a stress-inducible kinase since it was first cloned in 1999. Continued efforts since this time have been dedicated to characterizing the structure and function of SIK1. Such research has laid the ground work for our understanding of SIK1 action and regulation in tissue and stimuli dependent manners. The fundamental findings of this dissertation continue in this tradition and include investigations of SIK1 regulatory mechanisms in skeletal muscle cells, the cellular and physiological effects of SIK1 loss of function in vitro and in vivo, and intracellular metabolic and mitochondrial regulation by this …

Direct Antioxidant Properties Of Methotrexate: Inhibition Of Malondialdehyde-Acetaldehyde-Protein Adduct Formation And Superoxide Scavenging., Matthew C. Zimmerman, Dahn L. Clemens, Michael J. Duryee, Cleofes Sarmiento, Andrew Chiou, Carlos D. Hunter, Jun Tian, Lynell W. Klassen, James R. O'Dell, Geoffrey M. Thiele, Ted R. Mikuls, Daniel R. Anderson

Journal Articles: Cellular & Integrative Physiology

Methotrexate (MTX) is an immunosuppressant commonly used for the treatment of autoimmune diseases. Recent observations have shown that patients treated with MTX also exhibit a reduced risk for the development of cardiovascular disease (CVD). Although MTX reduces systemic inflammation and tissue damage, the mechanisms by which MTX exerts these beneficial effects are not entirely known. We have previously demonstrated that protein adducts formed by the interaction of malondialdehyde (MDA) and acetaldehyde (AA), known as MAA-protein adducts, are present in diseased tissues of individuals with rheumatoid arthritis (RA) or CVD. In previously reported studies, MAA-adducts were shown to be highly immunogenic, …

Carotid Body-Mediated Chemoreflex Drive In The Setting Of Low And High Output Heart Failure., Rodrigo Del Rio, David C. Andrade, Camilo Toledo, Hugo S. Diaz, Claudia Lucero, Alexis Arce-Alvarez, Noah J. Marcus, Harold D. Schultz

Journal Articles: Cellular & Integrative Physiology

Enhanced carotid body (CB) chemoreflex function is strongly related to cardiorespiratory disorders and disease progression in heart failure (HF). The mechanisms underlying CB sensitization during HF are not fully understood, however previous work indicates blood flow per se can affect CB function. Then, we hypothesized that the CB-mediated chemoreflex drive will be enhanced only in low output HF but not in high output HF. Myocardial infarcted rats and aorto-caval fistulated rats were used as a low output HF model (MI-CHF) and as a high output HF model (AV-CHF), respectively. Blood flow supply to the CB region was decreased only in …

Co-Modulation Masking Release Begins In The Auditory Periphery, Kareem R. Hussein, Agudemu Borjigan, Mark Sayles

The Summer Undergraduate Research Fellowship (SURF) Symposium

Understanding speech in noisy environments can be difficult, especially for people with hearing loss. The background noise can cover up the sounds of interest. Normally, the auditory system works to alleviate this problem by tagging and then cancelling the noise. Our experiments are aimed at understanding the mechanism of this noise cancellation process. We hypothesize that non-linear signal processing in the mammalian cochlea (the most peripheral part of the auditory system) is the basis of noise cancellation. To test this hypothesis, we measured the responses of auditory-nerve fibers (ANFs) to sounds embedded in background noise with different statistical properties. ANFs …

H2s And Homocysteine Control A Novel Feedback Regulation Of Cystathionine Beta Synthase And Cystathionine Gamma Lyase In Cardiomyocytes., Shyam Sundar Nandi, Paras K. Mishra

Journal Articles: Cellular & Integrative Physiology

Hydrogen sulfide (H2S), a cardioprotective gas, is endogenously produced from homocysteine by cystathionine beta synthase (CBS) and cystathionine gamma lyase (CSE) enzymes. However, effect of H2S or homocysteine on CBS and CSE expression, and cross-talk between CBS and CSE are unclear. We hypothesize that homocysteine and H2S regulate CBS and CSE expressions in a dose dependent manner in cardiomyocytes, and CBS deficiency induces cardiac CSE expression. To test the hypothesis, we treated murine atrial HL1 cardiomyocytes with increasing doses of homocysteine or Na2S/GYY4137, a H2S donor, and measured the levels of CBS and CSE. We found that homocysteine upregulates CSE …

Can Cone Signals In The Wild Be Predicted From The Past?, David H. Foster, Iván Marín-Franch

MODVIS Workshop

In the natural world, the past is usually a good guide to the future. If light from the sun and sky is blue earlier in the day and yellow now, then it is likely to be more yellow later, as the sun's elevation decreases. But is the light reflected from a scene into the eye as predictable as the light incident upon the scene, especially when lighting changes are not just spectral but include changes in local shadows and mutual reflections? The aim of this work was to test the predictability of cone photoreceptor signals in the wild over the …

Characterization Of Andrenocortical Tissue Morphology, Histology, And Steroid Synthesis Among Finetooth (Carcharhinus Isodon), Blacktip (Carcharhinus Limbatus), Atlantic Sharpnose (Rhizoprionodon Terraenovae), And Bonnethead (Sphyrna Tiburo) Sharks, Danielle Elizabeth Bailey

Master's Theses

Adrenocortical (interrenal) tissue is composed of steroidogenic cells that produce corticosteroids involved in the stress response and hydromineral balance. Previous research characterizing the elasmobranch interrenal suggests that the number of interrenal bodies that produce the single primary corticosteroid, 1a-hydroxycorticosterone (1a-OHB), varies among species. However, potential species-specific differences in the amount of interrenal tissue and major steroid products produced have been understudied. To address this critical gap in our understanding of elasmobranch biology, this study examined interrenal morphology, cell structure, steroidogenic enzyme distribution (3bHSD), and steroid production in four shark species: Finetooth Carcharhinus isodon, Blacktip Carcharhinus limbatus, Atlantic Sharpnose …

Diabetic Cardiomyopathy: An Immunometabolic Perspective., Paras K. Mishra, Wei Ying, Shyam Sundar Nandi, Gautam K. Bandyopadhyay, Kaushik K. Patel, Sushil K. Mahata

Journal Articles: Cellular & Integrative Physiology

The heart possesses a remarkable inherent capability to adapt itself to a wide array of genetic and extrinsic factors to maintain contractile function. Failure to sustain its compensatory responses results in cardiac dysfunction, leading to cardiomyopathy. Diabetic cardiomyopathy (DCM) is characterized by left ventricular hypertrophy and reduced diastolic function, with or without concurrent systolic dysfunction in the absence of hypertension and coronary artery disease. Changes in substrate metabolism, oxidative stress, endoplasmic reticulum stress, formation of extracellular matrix proteins, and advanced glycation end products constitute the early stage in DCM. These early events are followed by steatosis (accumulation of lipid droplets) …

Mitochondria Mediate Cell Membrane Repair And Contribute To Duchenne Muscular Dystrophy., Maria C Vila, Sree Rayavarapu, Marshall W Hogarth, Jack H Van Der Meulen, Adam Horn, Aurelia Defour, Shin'ichi Takeda, Kristy J. Brown, Yetrib Hathout, Kanneboyina Nagaraju, Jyoti K. Jaiswal

Genomics and Precision Medicine Faculty Publications

Dystrophin deficiency is the genetic basis for Duchenne muscular dystrophy (DMD), but the cellular basis of progressive myofiber death in DMD is not fully understood. Using two dystrophin-deficient mdx mouse models, we find that the mitochondrial dysfunction is among the earliest cellular deficits of mdx muscles. Mitochondria in dystrophic myofibers also respond poorly to sarcolemmal injury. These mitochondrial deficits reduce the ability of dystrophic muscle cell membranes to repair and are associated with a compensatory increase in dysferlin-mediated membrane repair proteins. Dysferlin deficit in mdx mice further compromises myofiber cell membrane repair and enhances the muscle pathology at an asymptomatic …

On The Origin Of Superoxide Dismutase: An Evolutionary Perspective Of Superoxide-Mediated Redox Signaling., Adam J. Case

Journal Articles: Cellular & Integrative Physiology

The field of free radical biology originated with the discovery of superoxide dismutase (SOD) in 1969. Over the last 5 decades, a plethora of research has been performed in species ranging from bacteria to mammals that has elucidated the molecular reaction, subcellular location, and specific isoforms of SOD. However, while humans have only begun to study this class of enzymes over the past 50 years, it has been estimated that these enzymes have existed for billions of years, and may be some of the original enzymes found in primitive life. As life evolved over this expanse of time, these enzymes …

Biomarkers Of Sepsis: A Retrospective Approach, Jose M. Roberts

Williams Honors College, Honors Research Projects

Background: Biomarkers are taking the spotlight in becoming the norm for early diagnoses. Sepsis is an inflammatory disease that increases metabolic rate in children. The first biomarker is hyponatremia. Hyponatremia is a frequent electrolyte imbalance in clinical practice, often observed in children with inflammatory disease and infection. Presence of hyponatremia is associated with electrical signaling imbalances, inflammation and renal dysfunction. The clinical value of hyponatremia in pediatric patients is unknown. The C-reactive protein is a second biomarker. Its presence signifies that necrotic cells and inflammation are present.

Objectives: To evaluate the use of biomarkers in children seen in the Emergency …

The Effect Of Cold On The Physiology Of Drosophila Larva Heart And On Synaptic Transmission At Crayfish Neuromuscular Junctions, Yuechen Zhu

Theses and Dissertations--Biology

Ectothermic animals are susceptible to temperature changes such as cold shock with seasons. To survive through a cold shock, ectotherms have developed unique strategies. My interest is focusing on the physiological function of during cold shock and prolonged cold exposure in the fruit fly (Drosophila melanogaster) and crayfish (Procambarus clarkii). I used Drosophila melanogaster as a model system to investigate cardiac function in response to modulators (serotonin, acetylcholine, octopamine, dopamine and a cocktail of modulators) in acute cold shock and chronic cold shock conditions as possible mechanism to regulate heart rate in the cold. To examine if the dampened heart …

Diabetes-Induced Expression And Regulation Of Glp-1 Levels By Bile Acid Receptors (Tgr5 & Fxr), Joseph R. Spengler

Theses and Dissertations

Diabetes Mellitus has continued to drastically affect the health of the world and many complications can prove fatal. As long as this metabolic disease persist, research discoveries will need to continue to be made so that patient outcomes and healthcare are dramatically enhanced. In recent years, GLP-1 has been the topic of conversation for diabetes research, due to its promising effects in promoting insulin sensitivity. Furthermore, bile acids and their receptors (TGR5 & FXR) have shown promise in their actions in the regulation of GLP-1, and thus glucose homeostasis. Here we have shown the detection and increased expression of TGR5 …

The Elasmobranch-Microbe Relationship: Trimethylamine N-Oxide Synthesis, Urea Hydrolysis, And Microbe-Osmolyte Interactions In The Atlantic Stingray, Dasyatis Sabina, Kaitlin Kelly Doucette

Master's Theses

The elasmobranch osmoregulatory strategy is predicated on the accumulation of nitrogenous compounds, primarily urea and trimethylamine n¬-oxide (TMAO). Despite the abundance of these plasma osmolytes, it is notable that elasmobranchs appear to lack urease and TMA oxidase (Tmase), enzymes that scavenge urea-nitrogen and synthesize TMAO, respectively. However, urease and Tmase are found in many species of bacteria. Therefore, I hypothesized that intestinal bacteria are responsible for urease and Tmase activity in elasmobranchs. Absent dietary nitrogen sources, I evaluated the effects of reduced intestinal microbiota on osmoregulation in Atlantic stingray (Dasyatis sabina) in vivo. D. sabina were given …