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Wayne State University Dissertations

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Full-Text Articles in Physiology

Preclinical Evaluation Of Infrared Light Therapy In A Rat Model Of Neonatal Hypoxic-Ischemic Encephalopathy, Christian Andrew Reynolds Jan 2015

Preclinical Evaluation Of Infrared Light Therapy In A Rat Model Of Neonatal Hypoxic-Ischemic Encephalopathy, Christian Andrew Reynolds

Wayne State University Dissertations

Hypoxic events encountered during the perinatal period leading to pathologic decreases in fetal cerebral oxygen availability are detrimental resulting in neonatal hypoxic-ischemic encephalopathy (HIE). This work focused on the characterization of a rat model of neonatal HIE for use in the preclinical evaluation of infrared light therapy (IRL). Consistent with results from previous IRL efficacy studies using a rat model of adult global brain ischemia, IRL treatment attenuated cerebral injury resulting from hypoxia-ischemia in the neonatal rat. Thus, and perhaps most importantly, this work contributes to the development of a potential novel therapeutic approach in the management of brain injuries …


Crebh, A Novel Liver Clock Keeper For Energy Metabolism, Ze Zheng Jan 2015

Crebh, A Novel Liver Clock Keeper For Energy Metabolism, Ze Zheng

Wayne State University Dissertations

Circadian rhythms play crucial roles in orchestrating diverse physiological processes that are critical for health and disease. Cyclic AMP responsive element binding protein 3-like 3 (CREB3L3, also known as CREBH) is a liver-enriched, endoplasmic reticulum (ER)-tethered transcription factor known to regulate hepatic acute-phase response and energy homeostasis under stress conditions. Here, we demonstrate that CREBH is regulated by the circadian clock and functions as a diurnal regulator of hepatic lipid and glucose metabolism. CREBH is required to maintain circadian profiles of blood triglycerides, fatty acids, and glucose as well as hepatic glycogen storage. CREBH rhythmically regulates expression levels and amplitudes …


Trophoblast Retrieval And Isolation From The Cervix (Tric) For Non-Invasive Prenatal Genetic Diagnosis And Prediction Of Abnormal Pregnancy Outcome, Rani Fritz Jan 2015

Trophoblast Retrieval And Isolation From The Cervix (Tric) For Non-Invasive Prenatal Genetic Diagnosis And Prediction Of Abnormal Pregnancy Outcome, Rani Fritz

Wayne State University Dissertations

The placenta is vital for the short- and long-term health of the fetus, and significantly impacts the health of the mother. During the first and second trimesters of pregnancy, extravillous trophoblast (EVT) cells invade the uterus and remodel the maternal spiral arteries, which, if inadequate, leads to pregnancy complications, including early pregnancy loss (EPL), preeclampsia (PE), and intra-uterine growth restriction (IUGR). EVT migration into the uterine wall is dependent on growth factors and cytokines that signal between maternal and fetal tissues. The epidermal growth factor (EGF) signaling system plays a significant role in trophoblast function. Using immunocytochemistry (ICC), we evaluated …


The Acute And Chronic Effects Of Resveratrol On Renal Function And Blood Pressure, Kevin L. Gordish Jan 2015

The Acute And Chronic Effects Of Resveratrol On Renal Function And Blood Pressure, Kevin L. Gordish

Wayne State University Dissertations

We investigated the acute and chronic effects of resveratrol on renal function and blood pressure. We hypothesized that resveratrol would act as a renal vasodilator through a nitric oxide-dependent mechanism. In our acute studies, we found an intravenous bolus of resveratrol influenced changes in renal hemodynamics by increasing renal blood flow and decreasing renal vascular resistance. The mechanism of renal vasodilation was nitric oxide dependent and through a reduction of endogenous reactive oxygen species. Resveratrol-induced renal vasodilation was not influenced by COX metabolism and vasodilatory prostanoids. We found with continuous intravenous resveratrol infusion induced significant renal vasodilation while not altering …


Investigation Of Whether Sedentary And Physically Active Conditions Lead To Altered Gabaergic Signaling In The Rvlm, Maryetta Donna Dombrowski Jan 2015

Investigation Of Whether Sedentary And Physically Active Conditions Lead To Altered Gabaergic Signaling In The Rvlm, Maryetta Donna Dombrowski

Wayne State University Dissertations

Investigation of whether sedentary and physically active conditions lead to altered GABAergic signaling in the RVLM

MD Dombrowski, and PJ Mueller

Department of Physiology, Wayne State University, School of Medicine, Detroit, MI

A sedentary lifestyle is a major risk for cardiovascular disease. Cardiovascular disease has been associated with elevated basal sympathetic nerve activity. The rostral ventrolateral medulla is a bilateral brainstem region that is an important for the control of resting and reflex control of sympathetic nerve activity and blood pressure. The activity of these neurons in this region is tonically inhibited by the neurotransmitter γ-butyric amino acid (GABA). Interestingly, …


Self-Construal Moderates Testosterone Reactivity To Competitive Outcomes, Keith Welker Jan 2014

Self-Construal Moderates Testosterone Reactivity To Competitive Outcomes, Keith Welker

Wayne State University Dissertations

Previous research shows that testosterone reactivity to competitive outcomes predicts aggressive behavior in men. However, some studies have failed to find these effects, and it has been suggested that individual differences moderate the relationships between competitive outcomes, testosterone fluctuations, and aggressive behavior. The current research examined whether one individual difference--self-construal--would moderate these effects. In Study 1, participants were assigned to win or lose a competitive video game and engaged in a reactive aggression task. Results indicated that increases in testosterone in response to winning and decreases in response to losing occurred in men with independent, not interdependent, self-construals. These changes …


Ribonomic Control During Global Brain Ischemia And Reperfusion, Haihui Wang Jan 2014

Ribonomic Control During Global Brain Ischemia And Reperfusion, Haihui Wang

Wayne State University Dissertations

Abstract

RIBONOMIC CONTROL DURING GLOBAL BRAIN ISCHEMIA AND REPERFUSION

by HAIHUI WANG

August 2014

Advisor: Donald J. DeGracia, Ph.D.

Major: Physiology

Degree: Doctor of Philosophy

The study presented here used "omic" technology to look at the mechanism behind the selective delayed death of hippocampus CA1 neurons after transient global brain ischemia. The main findings are summarized:

1. The main form of ELAV protein family member detected in CA1/CA3 in Hu protein immunoprecipitation and polysomes was HuB (Rel-N1). HuB is present in control CA3, 8 hr reperfused CA3, and 8 hr reperfused CA1, but absent from control CA1. AUF-1, hnRNP K, …


Regulation Of Nkcc2 Trafficking By Vesicle Fusion Proteins Vamp2 And Vamp3 In The Thick Ascending Limb, Paulo Sebastian Caceres Puzzella Jan 2014

Regulation Of Nkcc2 Trafficking By Vesicle Fusion Proteins Vamp2 And Vamp3 In The Thick Ascending Limb, Paulo Sebastian Caceres Puzzella

Wayne State University Dissertations

The thick ascending limb (TAL) in the kidney regulates extracellular fluid volume and blood pressure. The Na/K/2Cl cotransporter NKCC2 plays a central role in NaCl absorption by the TAL and blood pressure. NKCC2 trafficking to the apical membrane is a major mechanism to control NKCC2 activity. However, little is known about the proteins that mediate NKCC2 trafficking. Inhibition of the vesicle fusion proteins VAMP2 and VAMP3 blunts the increase in surface NKCC2 expression and NaCl absorption in response to stimulation by cAMP. In other cells, VAMPs mediate fusion of exocytic vesicles with the plasma membrane. Whether VAMP2 and VAMP3 mediate …


Mitochondrial Dynamics: Exploring A Novel Target Against Myocardial Ischemia-Reperfusion Injury, Yi Dong Jan 2014

Mitochondrial Dynamics: Exploring A Novel Target Against Myocardial Ischemia-Reperfusion Injury, Yi Dong

Wayne State University Dissertations

Mitochondrial fusion and fission, collectively termed mitochondrial dynamics, are among the core mechanisms responsible for maintaining mitochondrial health and functional integrity. Dynamin-related protein 1 (DRP1) is a key regulator of mitochondrial fission. Recent studies suggest that i) mitochondrial dynamics, particularly, mitochondrial fission, serves as a mediator of cell fate in the setting of ischemia-reperfusion (IR) injury, and, ii) inhibition of DRP1 and mitochondrial fission provides cardioprotection against IR injury. However, the precise role of DRP1 translocation to mitochondria in the pathogenesis of myocardial ischemia-reperfusion injury has not been established.

Using an established model of hypoxia-reoxygenation (HR) in cultured HL-1 cardiomyocytes, …


Muscle Metaboreflex Control Of Cardiovascular Function In Hypertension, Marty Daniel Spranger Jan 2014

Muscle Metaboreflex Control Of Cardiovascular Function In Hypertension, Marty Daniel Spranger

Wayne State University Dissertations

Skeletal muscle ischemia during or immediately following exercise leads to the accumulation of metabolites (e.g., lactate, proton and diprotonated phosphate) which activate chemoreceptive afferents within the muscle leading to a reflex increase in sympathetic outflow generating substantial increases in mean arterial pressure (MAP), cardiac output (CO) and heart rate (HR) - termed the muscle metaboreflex. When the reflex is activated during submaximal dynamic exercise, the pressor response occurs via increased CO with no net peripheral vasoconstriction. When metaboreflex activation is sustained during the recovery from exercise (i.e., post-exercise muscle ischemia - (PEMI)), whereas MAP remains elevated for as long as …


Cervical Remodeling/Ripening At Term And Preterm Delivery: The Same Mechanism Initiated By Different Mediators And Different Effector Cells, Juan Miguel Gonzalez Velez Jan 2014

Cervical Remodeling/Ripening At Term And Preterm Delivery: The Same Mechanism Initiated By Different Mediators And Different Effector Cells, Juan Miguel Gonzalez Velez

Wayne State University Dissertations

Premature cervical remodeling/ripening is believed to contribute to preterm delivery (PTD), the leading cause of perinatal morbidity and mortality. Despite considerable research, the causes of term and PTD remain unclear, and there is no effective treatment for PTD. We tested the hypothesis that complement activation plays a role in cervical remodeling and PTD. We studied cervical remodeling at term.

We studied two mouse models of inflammation-induced PTD. The first model was induced by vaginal administration of lipopolysaccharide (LPS)and the second one by administration of progesterone antagonist RU486. Increased cervical C3 deposition and macrophage infiltration and increased serum C3adesArg and C5adesArg …


Blast-Induced Tinnitus: A Combined Behavioral, Memri, And Electrophysiology Study, Jessica Pengyun Ouyang Jan 2014

Blast-Induced Tinnitus: A Combined Behavioral, Memri, And Electrophysiology Study, Jessica Pengyun Ouyang

Wayne State University Dissertations

ABSTRACT

BLAST-INDUCED TINNITUS: A COMBINED BEHAVIORAL, MEMRE, AND ELECTROPHYSIOLOGY STUDY

by

JESSICA OUYANG

May 2014 Advisor: Drs. Steve Cala & Jinsheng Zhang

Major: Physiology

Degree: Doctor of Philosophy

Tinnitus and hearing loss are the frequent auditory-related co-morbidities of blast trauma. The etiology of blast-induced tinnitus is also muddled by brain mechanisms associated with emotional and cognitive problems such as anxiety, memory loss, and depression. We set out to develop a realistic and ecologically valid model to address changes of cognitive status and psychological state that are associated with blast- induced tinnitus. In this study, 19 adult rats were randomly divided …


The Effect Of Body Position On Cerebral Bllod Flow, Cognition, Cardiac Output, Map,And Motor Function In Patients Undergoing Shoulder Surgery : Lateral Versus Beach Chair Position Under General Anesthesia, Kelley Labonty Jan 2014

The Effect Of Body Position On Cerebral Bllod Flow, Cognition, Cardiac Output, Map,And Motor Function In Patients Undergoing Shoulder Surgery : Lateral Versus Beach Chair Position Under General Anesthesia, Kelley Labonty

Wayne State University Dissertations

ABSTRACT

The Effect of Body Position on Changes in Cerebral Blood Flow, Cognition, and Motor Function in Patients Undergoing Shoulder Surgery: Lateral versus Beach Chair Position Under General Anesthesia

By

KELLEY LABONTY

December 2013

Advisor: Dr. Steven Cala

Major: Physiology

Degree: Doctor of Philosophy

This study aims to determine if there are alterations in cerebral perfusion in patients undergoing general anesthesia in the sitting position. With the reporting of 15 catastrophic cerebral vascular accidents recently being published during shoulder surgery in the sitting position, an increase of 90 times from previously reported data, there has become a clear need for …


Altered Morphology And Composition Of Zymogen Granules In Acute Pancreatitis, Amanda Flack Jan 2014

Altered Morphology And Composition Of Zymogen Granules In Acute Pancreatitis, Amanda Flack

Wayne State University Dissertations

In healthy physiology, pancreatic digestive enzymes secreted following a meal are stored as inactive zymogens within membrane bound secretory vesicles called Zymogen Granules (ZG), and activated extracellularly. In acute pancreatitis however, the digestive enzymes are prematurely activated within the cell, resulting in autodigestion of the tissue. Pancreatitis is a gastrointestinal disorder in which there are over 200,000 hospitalizations per year with a 5% mortality rate. It has been demonstrated that in acute pancreatitis the digestive enzymes are blocked from being secreted and are activated within the cell leading to acinar cell and surrounding pancreatic tissue death. Little is known about …


Junctional Sarcoplasmic Reticulum Protein Processing And Trafficking In Cardiac Tissue And Primary Cultured Cardiomyocytes, Naama Sleiman Jan 2014

Junctional Sarcoplasmic Reticulum Protein Processing And Trafficking In Cardiac Tissue And Primary Cultured Cardiomyocytes, Naama Sleiman

Wayne State University Dissertations

Junctional SR is an important and unique ER subdomain in the adult myocyte that releases Ca2+ through the actions of an exclusive set of resident proteins. Cardiac calsequestrin (CSQ2) undergoes two co-translational modifications: N-linked glycosylation on 316Asn, and phosphorylation by protein kinase CK2 on a cluster of 3 serines in its tail. In the heart, CSQ2 molecules undergo extensive mannose trimming by ER mannosidase(s), a posttranslational process that often regulates protein breakdown. To investigate CSQ2 protein processing in cardiomyopathy models, studies were performed to test whether CSQ2 glycan structures would be altered in heart tissue from mongrel dogs induced into …


Adenosine A2b Receptor Effects On Post-Mi Remodeling And Cardiac Fibroblast Function, Enbo Zhan Jan 2014

Adenosine A2b Receptor Effects On Post-Mi Remodeling And Cardiac Fibroblast Function, Enbo Zhan

Wayne State University Dissertations

Adenosine A2B receptor (A2BR) appear to contribute to chronic inflammation. This receptor is highly expressed in macrophages and cardiac fibroblasts, cells which play key roles in inflammation and healing following myocardial infarction (MI). A2BR have been shown to induce collagen production and promote organ fibrosis, although the reports of A2BR role on MI are limited and conflicting. The results of cardiac fibroblast (CF) studies however suggest that non-selective A2BR stimulation inhibits collagen expression. The hypothesis of the present study was that deletion of A2BR reduces adverse remodeling in post-MI, …


The Role Of Oxidative Stress In The Pathogenesis Of Epithelial Ovarian Cancer, Nicole Marie King Jan 2013

The Role Of Oxidative Stress In The Pathogenesis Of Epithelial Ovarian Cancer, Nicole Marie King

Wayne State University Dissertations

Ovarian cancer is the leading cause of death from gynecologic malignancies yet the underlying pathophysiology is not clearly established. The disease is usually diagnosed in the advanced stage and carries a poor prognosis. The 5-year survival rate is greater than 75% if diagnosis of the cancer occurs at an early stage; however, this rate drops to 20% when the tumor has spread beyond its origin. Thus, a method for early detection is critically needed, which can help prolong, or even save lives. Currently, an effective screening test for ovarian cancer is lacking. Many tests have been evaluated but have been …


Characterization Of High-Voltage-Activated Calcium Channels In Retinal Bipolar Cells, Qi Lu Jan 2013

Characterization Of High-Voltage-Activated Calcium Channels In Retinal Bipolar Cells, Qi Lu

Wayne State University Dissertations

Retinal bipolar cells, conveying visual information from photoreceptors to ganglion cells, segregate visual information into multiple parallel pathways through their diversified cell types and physiological properties. Voltage-gated Ca2+ channels could be particularly important underlying the diversified physiological properties of different BCs. In this dissertation, I investigated the high-voltage-activated (HVA) calcium current in retinal bipolar cells in mice. In the first part of my dissertation, I characterized multiple bipolar cell-expressing GFP and/or Cre transgenic mouse lines. In the second part of my dissertation, by performing whole-cell patch-clamp recordings, I examined the electrophysiological properties of HVA calcium currents among CBCs and …


Thick Ascending Limb Nitric Oxide Production And Inhibition Of Nkcc2 Activity Are Impaired In Angiotensin Ii-Induced Hypertension, Vanesa Daniela Ramseyer Jan 2013

Thick Ascending Limb Nitric Oxide Production And Inhibition Of Nkcc2 Activity Are Impaired In Angiotensin Ii-Induced Hypertension, Vanesa Daniela Ramseyer

Wayne State University Dissertations

Cardiovascular disease is the leading cause of death in the US. Hypertension, which affects about 30 % of the US population, is an important risk factor in the development of this disease. Inappropriately elevated sodium reabsorption by the kidney contributes to hypertension; therefore, studying the mechanisms that lead to enhanced sodium transport is important in understanding this pathology. The thick ascending limb (THAL) reabsorbs 30% of the filtered sodium chloride load. Nitric oxide (NO) produced by NO synthase type 3 (NOS3) increases cyclic GMP (cGMP) and inhibits THAL transport by reducing Na/K/2Cl cotransporter type 2 (NKCC2) activity. Interestingly, in angiotensin …


Mechanisms Mediating Modulation Of The Cardiopulmonary Chemoreflex Control Of Regional Sympathetic Outputs By Adenosine A1 And A2a Receptors In The Nts, Zeljka Minic Jan 2013

Mechanisms Mediating Modulation Of The Cardiopulmonary Chemoreflex Control Of Regional Sympathetic Outputs By Adenosine A1 And A2a Receptors In The Nts, Zeljka Minic

Wayne State University Dissertations

ABSTRACT

by

ZELJKA MINIC

August 2013

Advisor: Dr. Tadeusz J. Scislo

Major: Physiology

Degree: Doctor of Philosophy

Adenosine is an important neuromodulator of cardiovascular control at the level of the nucleus of the solitary tract (NTS) where cardiovascular and other autonomic reflexes are primarily integrated. Levels of adenosine increase in the NTS during life threatening hypotension, ischemia and hypoxia. Adenosine may modulate cardiovascular reflexes to correct hemodynamic imbalance, acting via A1 and A2a receptors which inhibit and facilitate neurotransmitter release, respectively. Previous studies from our laboratory showed that NTS A1 adenosine receptors inhibit the arterial baroreflex whereas …


Fatty Acid Fate In Determining Oxidation And Inflammation In Adipose Tissue, Emilio Patrick Mottillo Jan 2013

Fatty Acid Fate In Determining Oxidation And Inflammation In Adipose Tissue, Emilio Patrick Mottillo

Wayne State University Dissertations

Adipose tissue (AT) is a critical regulator of energy balance through its ability to store or oxidize free fatty acids (FFAs). White adipose tissue (WAT) functions as an anabolic organ to sequester and release FAs, in contrast brown adipose tissue (BAT) is a catabolic organ that oxidizes FAs. However, a comprehensive understanding of the role that FFAs play in the function of WAT and BAT is needed. Here we demonstrate that intracellular FAs enhance the expression of inflammatory cytokines by β3-AR activation in adipocytes, in which the expression of PAI-1 is partly mediated by the de novo synthesis of ceramides/sphingolipids. …


Linking Environmental Toxicant Exposure To Diabetes Susceptibility, Jannifer Beth Tyrrell Jan 2013

Linking Environmental Toxicant Exposure To Diabetes Susceptibility, Jannifer Beth Tyrrell

Wayne State University Dissertations

An important and unresolved question in the environmental health field is whether exposure to common environmental toxicants, such as dioxin and heavy metals like Pb, increase the risk of developing diabetes, especially in combination with other common metabolic stressors such as obesity.

Previous studies suggested that dioxin exposure increased peripheral insulin resistance but did not appear to cause fasting hyperglycemia or elevated hepatic glucose output. In concordance with those findings we observed that dioxin treatment caused a strong suppression of the expression of the key hepatic gluconeogenic genes PEPCK and G6Pase. However, this suppression was not solely mediated by the …


Modulation Of Renin Secretion By Renal Cortical Interstitial Calcium, Douglas K. Atchison Jan 2013

Modulation Of Renin Secretion By Renal Cortical Interstitial Calcium, Douglas K. Atchison

Wayne State University Dissertations

Renin is secreted from the juxtaglomerular (JG) cells of the afferent arteriole of the kidney, and is the rate-limiting enzyme of the renin-angiotensin system. Renin is quantified in vivo as plasma renin activity (PRA). Acutely elevating plasma calcium decreases PRA, but the mechanisms by which this occurs is unknown. The overall goal of our study was to determine how elevated plasma calcium decreases PRA. The calcium-sensing receptor (CaSR) is a ubiquitously expressed receptor that translates changes in plasma calcium into changes in intracellular signaling. JG cells are basolaterally bordered by the renal cortical interstitium, and parathyroid hormone (PTH) positively regulates …


Investigation Of Posttranscriptional Regulation After Global Brain Ischemia And Reperfusion Injury, Jeffrey J. Szymanski Jan 2012

Investigation Of Posttranscriptional Regulation After Global Brain Ischemia And Reperfusion Injury, Jeffrey J. Szymanski

Wayne State University Dissertations

The final cause of death in most patients revived after cardiac arrest is ischemia and reperfusion (I/R) injury in the brain. Survival after brain I/R injury depends on the expression of new stress response proteins such as heat shock protein 70 (HSP70). Little is known about why recovering neurons are able to express new stress response proteins while neurons that will die can transcribe RNA but do not translated protein in early reperfusion. Previous studies suggested that the mRNA-binding protein HuR may regulate hsp70 mRNA in reperfused neurons through a novel cytoplasmic structure, the mRNA granule. To determine the roles …


Sex Differences In The Cardiac Beta-Adrenergic Receptor Contractile Response, Victoria Mcintosh Jan 2012

Sex Differences In The Cardiac Beta-Adrenergic Receptor Contractile Response, Victoria Mcintosh

Wayne State University Dissertations

Premenopausal females are at a reduced risk for developing cardiovascular disease as compared to males; this sex difference is not present following menopause. &beta-adrenergic receptors are pharmaceutical targets in the treatment of cardiovascular disease, and sex differences in &beta-adrenergic responsiveness have been demonstrated. However, limited studies have addressed the mechanism(s) underlying these differences. To investigate these sex differences, studies were performed using isolated perfused hearts from male, intact female and ovariectomized female mice, as well as male and female ventricular myocytes. Female hearts exhibited blunted contractile responses to the &beta-adrenergic receptor agonist isoproterenol (ISO) compared to males but not ovariectomized …


Mechanisms Of Persistent Translation Arrest Following Global Brain Ischemia And Reperfusion, Jill Theresa Jamison Jan 2011

Mechanisms Of Persistent Translation Arrest Following Global Brain Ischemia And Reperfusion, Jill Theresa Jamison

Wayne State University Dissertations

ABSTRACT

MECHANISMS OF PERSISTENT TRANSLATION ARREST FOLLOWING GLOBAL BRAIN ISCHEMIA and REPERFUSION

by

JILL T. JAMISON

December 2011

Advisor: Donald J. DeGracia, Ph.D.

Major: Physiology

Degree: Doctor of Philosophy

The information presented here studies the mechanisms that underlie persistent translation arrest (TA) following global brain ischemia and reperfusion (I/R). To summarize the main findings I have discovered a new mechanism for prolonged post-ischemic TA that correlated exactly with in vivo translation rates and correlated precisely with cell outcome. Through the extensive colocalization studies, my results indicate that the mRNA granules are ribonomic structures involved with mRNA regulation. This finding is …


Muscle Metaboreflex Control Of Coronary Blood Flow And Ventricular Contractility During Dynamic Exercise In Normal And Heart Failure Conditions, Matthew Coutsos Jan 2011

Muscle Metaboreflex Control Of Coronary Blood Flow And Ventricular Contractility During Dynamic Exercise In Normal And Heart Failure Conditions, Matthew Coutsos

Wayne State University Dissertations

Muscle metaboreflex activation during dynamic exercise induces a substantial increase in cardiac work and oxygen demand via a significant increase in heart rate, ventricular contractility and afterload. This increase in cardiac work should cause coronary metabolic vasodilation. However, little if any coronary vasodilation is observed due to concomitant sympathetically induced coronary vasoconstriction. In heart failure, cardiac output does not increase with MMA presumably due to impaired left ventricular contractility, and large decreases in coronary vascular conductance are observed. The purpose of this dissertation is to determine whether the muscle metaboreflex-induced restraint of coronary vasodilation functionally limits coronary blood flow and …


Molecular Mechanisms Of Snare Assembly And Expulsion Of Intravesicular Contents In Cell Secretion, Leah Jiyoung Zhang Jan 2011

Molecular Mechanisms Of Snare Assembly And Expulsion Of Intravesicular Contents In Cell Secretion, Leah Jiyoung Zhang

Wayne State University Dissertations

For nearly half a century, it was believed that during cell secretion, membrane-bound secretory vesicles completely merge at the cell plasma membrane resulting in the diffusion of intra-vesicular contents to the cell exterior and the compensatory retrieval of the excess membrane by endocytosis. This explanation made no sense or logic, since following cell secretion partially empty vesicles accumulate as demonstrated in electron micrographs. Furthermore, with the `all or none' mechanism of cell secretion by complete merger of secretory vesicle membrane at the cell plasma membrane, the cell is left with little regulation and control of the amount of content release. …


Mechanisms Of Translation Arrest Following Focal Brain Ischemia, Monique K. Lewis Jan 2011

Mechanisms Of Translation Arrest Following Focal Brain Ischemia, Monique K. Lewis

Wayne State University Dissertations

MECHANISMS OF TRANSLATION ARREST FOLLOWING FOCAL BRAIN

ISCHEMIA

by

MONIQUE K. LEWIS

August 2011

Advisor: Dr. Donald DeGracia

Major: Physiology

Degree: Doctor of Philosophy

The loss of blood flow to the brain is termed ischemia and the subsequent resumption of blood flow is termed reperfusion. Brain ischemia and reperfusion (I/R) occurs primarily following resuscitation from cardiac arrest and stroke and presents one of the most significant clinical challenges. At present, there are no clinically effective pharmacologic interventions to halt brain damage following I/R. The major Aim of this dissertation will be to investigate possible mechanisms involved in neuron death following …


Destruction Of Biological Tetrapyrrole Macrocycles By Hypochlorous Acid And Its Scavenging By Lycopene, Dhiman Maitra Jan 2011

Destruction Of Biological Tetrapyrrole Macrocycles By Hypochlorous Acid And Its Scavenging By Lycopene, Dhiman Maitra

Wayne State University Dissertations

Hypochlorous acid (HOCl) is a potent oxidant generated by the hemoprotein myeloperoxidase. Although HOCl plays an important role in the innate immune response,sustained high levels of HOCl has been implicated to play a harmful role. In several pathological conditions such as atherosclerosis, endometriosis and sickle cell disease where HOCl is elevated there are reports of significant free iron accumulation. Free iron is toxic since it can lead to the generation of other secondary free radicals such as hydroxyl radical by Fenton reaction. The exact source and mechanism by which the free iron is generated is not clearly understood. This work …