Human Thermoregulation Laboratory
W. Larry Kenney, Ph. D.
Professor of Physiology and Kinesiology
Dr. Kenney’s research focus primarily includes environmental and exercise physiology, particularly human thermoregulation, skin blood flow, and the biophysics of heat exchange. Also, his interests include thermoregulation under conditions of disease and with drug-intervention
Overview of Primary Research:
Blood Flow in Aged Skin: Our laboratory has spent the past 20 years systematically examining the mechanisms of age-related attenuated reflex cutaneous vasoconstriction (VC) and vasodilation (VD). This attenuated reflex cutaneous vasoreactivity with human aging is due to a functional loss of adrenergic VC and active cholinergic VD co-transmitter function. Our current studies are examining the role of oxidant-induced reduced tetrahydrobiopterin (BH4) bioavailability in the aged cutaneous vasculature. Human aging is associated with a globalized increase in oxidant stress resulting from an increased production and decreased clearance of reactive oxygen molecules, leading to the destruction of the critical enzymatic cofactor BH4. BH4 is ubiquitous throughout neural and vascular tissues and is a viable molecular target that may underlie both attenuated reflex cutaneous VC and VD mechanisms.
High Cholesterol and Skin Blood Flow: Elevated concentrations of low density lipoproteins are highly atherogenic and independently associated with the severity of coronary atherosclerosis. One early indicator of hypercholesterolemic-associated vascular disease is a decrease in endothelial-derived nitric oxide (NO). In this series of studies we are examining the underlying mechanisms mediating hypercholesterolemic vascular dysfunction in the cutaneous microcirculation. We are further examining the effects of the most commonly prescribed cholesterol lowering therapy on mechanisms meditating microvascular reactivity in human skin. Drs. W. Larry Kenney and Lacy Holowatz collaborate on this project.
Platelet Inhibition and Skin Blood Flow: Low-dose aspirin (ASA) therapy isutilized clinically in healthy populations to inhibit cyclooxygenase-1 (COX-1) in platelets for atherothrombotic prevention, however, chronic COX-inhibition with low-dose aspirin consistently and significantly attenuates reflex cutaneous vasodilation. Our ongoing studies are examining the potential roles of 1) platelet activation, and alterations in blood viscoelastic properties on shear-induced vasodilation and 2) thefunctional consequences of platelet inhibitor-induced attenuation in skin blood flow during exercise in the heat. Drs. W. Larry Kenney and Lacy Holowatz collaborate on this project.
(L to R Back:) Susan Beyerle, Lacy Alexander, and Caroline Smith
(L to R Front): Sue Slimak, Jessie Kutz, Jane Pierzga, Anna Stanhewicz,
W. Larry Kenney, and Rebecca Bruning
Assistants: Jane Pierzga, M.S. – Faculty Research Assistant
Susan Slimak, R.N. – Research Nurse
Graduate Students: Rebecca Bruning
- Aging and Skin Blood Flow (NIH) R01 AG07004
- Hypercholesterolemia and Human Skin Blood Flow (NIH) R01 HL089302