Research

Our research goal is to establish the Physiology Research Program of the College of Biomedical and Translational Sciences of the University of North Texas Health Science Center at Fort Worth as an nationally and internationally recognized program of research and pre-doctoral and post-doctoral training. The core of the department’s research is the physiology and pathophysiology of the cardiovascular system. Our members are nationally and internationally recognized in their specific areas of research. Faculty members of the department serve on grant review panels for the National Institutes of Health and the American Heart Association, as well as the editorial boards of prestigious cardiovascular journals, and hold offices in several scientific and clinical organizations.

Current Research Projects

Mark Cunningham, Ph.D., Assistant Professor
(Ph.D., Physiology and Functional Genomics, University of Florida School of Medicine, 2014) My research interest examines the mechanisms (such as inflammation, mitochondrial dysfunction, decreased nitric oxide bioavailability, and increase oxidative stress) of cerebrovascular dysfunction, cardiovascular disease (CVD), and hypertension in women (during pregnancy and postpartum) with hypertensive pregnancy complications and their offspring. Preeclampsia (PE), hypertension during pregnancy, not only affects the mother’s short-term (during pregnancy) and long-term (post-partum) health, but also the health of the neonates into adulthood. Two important factors that are associated with PE are Interleukin 17(IL-17) and the angiotensin II type 1 receptor agonistic autoantibodies (AT1-AA). My current research endeavor is to determine if blockade or interference with IL-17 and/or AT1-AAs during PE can improve maternal and fetal outcomes during pregnancy and later in life. My research areas of expertise include and are not limited to hypertension, women’s health, pregnancy, preeclampsia, and fetal programming.

J. Thomas Cunningham, Ph.D., Regents Professor and Associate VP of Research Administration
(Ph.D., Biopsychology, University of Iowa, 1988) We investigate the role of the central nervous system in body fluid homeostasis and cardiovascular regulation. Current projects focus on the physiological regulation of vasopressin release by visceral afferents and the roles of hypothalamic TRP channels and brain derived neurotrophic factors in syndrome of inappropriate ADH (SIADH). We also study hypothalamic mechanisms that influence sympathetic outflow in animal models of hypertension.

Greg Dick, Ph.D., Research Associate Professor
(Ph.D., Physiology, University of Missouri, 1996) Our research is focused on the potassium channels of coronary artery smooth muscle and how they control blood flow to the heart muscle. Evidence supports the idea that multiple signaling pathways converge on smooth muscle potassium channels to modulate coronary vascular tone. Although many types of potassium channels are expressed in coronary vascular smooth muscle, voltage-dependent channels appear to play a predominant role, as inhibition of these channels reduces coronary blood flow and inhibits vasodilation in response to metabolism and ischemia. We use an integrative approach to study these voltage-dependent potassium channels. This approach includes sensitive measurements of the opening and closing of single potassium channels in isolated smooth muscle cells all the way up to measurement of coronary blood flow in the beating heart.

Gef Farmer, Ph.D., Research Assistant Professor
(Ph.D., Cognition and Neuroscience, University of Texas at Dallas, 2012) My current research interests involve the study of the brain renin-angiotensin system and the role it plays in neural plasticity. Currently, my work focuses on understanding the mechanisms that regulate the synthesis and release of angiotensin II within the brain in response to chronic intermittent hypoxia, an animal model that simulates the hypoxemia associated with sleep apnea. Furthermore, I investigate how dysregulation of angiotensin signaling can contribute to pathogenesis such as the development of hypertension commonly associated with sleep apnea. In my research group, we have developed the use of sniffer cell line to detect the spontaneous and evoked release of angiotensin II in an in vitro preparation. Additionally, our research group has shown that angiotensin II signaling can influence the excitability of neurons in the median preoptic nucleus, an integrative brain structure that contributes to the sustained hypertension associated with sleep apnea, through the regulation of potassium-chloride co-transporters.

Rong Ma, Ph.D., Professor
(Ph.D., Physiology, University of Nebraska, 1999) Research focuses on Ca2+-conductive channels (TRP channels) in kidney (glomerular mesangial cells and podocytes) and vascular smooth muscle cells. Major interests include regulation of TRP channels by protein kinases and reactive oxygen species, physiological relevance of TRP channels in kidney and blood vessels, and the association of TRP channel dysfunction with kidney and vascular diseases, such as diabetic nephropathy and vasculopathy

Robert T. Mallet, Ph.D., Regents Professor
(Ph.D., Physiology, George Washington University, 1986) Research emphasizes development of novel strategies to protect heart and brain from ischemic and inflammatory injury by modifying metabolic fuel supply to these organs, or by hypoxia conditioning. Current studies are defining mechanisms responsible for protection of the heart and brain by pyruvate during cardiac arrest-resuscitation, cardiopulmonary bypass surgery and hemorrhagic shock, and robust preservation of ischemic heart muscle and brain by intermittent, normobaric hypoxia conditioning.

Keisa W. Mathis, Ph.D., Associate Professor
(Ph.D, Physiology, LSU Health Sciences Center, 2009) The primary focus of the Mathis Laboratory is to investigate neuroimmune mechanisms that contribute to the pathogenesis of hypertension and renal injury. We are interested in systemic lupus erythematosus (SLE), an autoimmune disease with a high prevalence of hypertension that primarily affects young women. The autonomic dysfunction and chronic inflammation in SLE makes it an ideal disease model to study neuroimmune interactions that may lead to alterations in the kidney and ultimately hypertension. We are currently investigating the vagally-mediated, cholinergic anti-inflammatory pathway and its role in the development of chronic inflammation and hypertension in a mouse model of SLE using integrative physiological approaches complimented with molecular, cellular and immunological techniques. Our research may lead to important clinical implications for not only patients with SLE and essential hypertension, but also for patients with other diseases of chronic inflammation.

Caroline Rickards, Ph.D., Associate Professor
(Ph.D., Doctor of Physiology, RMIT University Melbourne, Australia, 2005)  General research research interests encompass understanding the integrated cardiovascular, autonomic and cerebrovascular responses to hypovolemic stressors in humans, with an emphasis on hemorrhage and orthostasis. While working with the US Army at the Institute for Surgical Research in San Antonio, my research focused on the early detection of hemorrhagic injury in trauma patients, and characterizing physiological differences between individuals with high versus low tolerance to this stress.  My current projects in the Department of Integrative Physiology and Anatomy continue this line of investigation, with a particular focus on examining the role of hemodyamic variability (i.e., in arterial pressure and cerebral blood flow) on the protection of cerebral tissue perfusion and oxygenation.  It is anticipated that these studies will have potential clinical applications to stroke, traumatic brain injury, hemorrhage, migraine, and orthostatic intolerance.

Steven Romero, Ph.D., Associate Professor
(Ph.D., Human Physiology, University of Oregon, 2014 ) The Human Vascular Physiology Laboratory has two primary research themes. The first research theme centers on investigating how the human vascular system adjusts and adapts to exercise and environmental stress in healthy and diseased populations. The second research theme centers on examining the vascular and functional maladaptations that accompany various diseases (e.g. hypertension, aging, peripheral arterial disease), in addition to identifying novel therapies that may mitigate such detrimental changes.

Ann Schreihofer, Ph.D., Professor
(Ph.D., Neuroscience, University of Pittsburgh, 2004) Research efforts focus on how the brain regulates the cardiovascular system in health and disease states.  The laboratory uses a combination of electrophysiological, neuroanatomical, molecular, and physiological approaches to investigate how the brain modulates the autonomic nervous system to maintain blood pressure.  Using rats, the laboratory is currently focused how obesity (and metabolic syndrome) and exposure to chronic intermittent hypoxia (as a model for obstructive sleep apnea) alter autonomic regulation of blood pressure to promote hypertension.

Michael L. Smith, Ph.D., Professor
(Ph.D., Biology, University of North Texas, 1986). Research efforts focus on the neural control of cardiovascular function relating to mechanisms of sudden cardiac death, syncope, exercise training effects, and mechanisms of the association between obstructive sleep apnea and hypertension.

Johnathan Tune, Ph.D., Professor and Chair
(Ph.D., Physiology, University of North Texas Health Science Center, 1997). Research in the Tune laboratory focuses on the regulation of myocardial oxygen delivery, contractile function and metabolism in health and disease. The primary goal centers on elucidating mechanisms of impaired coronary and cardiac function in the setting of obesity and diabetes. More specifically, experiments are designed to delineate putative mechanisms responsible for the regulation of coronary blood flow, identify factors that contribute to the initiation and progression of coronary vascular dysfunction and disease, and protecting the heart from irreversible ischemic damage. Studies routinely include a series of highly integrative experimental approaches which utilize both in vivo and in vitro approaches in large animal models of disease.