Graig Crandall, Ph.D.

 

Associate Professor of Internal Medicine at the University of Texas Southwestern Medical Center, Research Scientist at the Institute for Exercise and Environmental Medicine at Presbyterian Hospital of Dallas. 

 

Dr. Crandall received a doctorate in Physiology from the University of North Texas Health Science Center at Fort Worth under the direction of Dr. Peter Raven, followed by post-doctoral training from Dr. John Johnson at the University of Texas Health Science Center at San Antonio.  Dr. Crandall's research interests focus on the interaction between thermal and cardiovascular reflexes.  He has authored over 60 scientific publications.

 

Heat stress and neural control of the circulation in humans

Heat stress results in significant cardiovascular adjustments as evidenced by pronounced increases in heart rate, cardiac contractility, sympathetic activity, and reductions in renal and splanchnic vascular conductance.  In humans these events are accompanied by marked reductions in orthostatic tolerance.  Mechanisms by which heat stress reduces orthostatic tolerance remain unclear.  Possible mechanisms that will be addressed include altered baroreflex responsiveness as well as attenuated vasoconstriction to adrenergic agents.