WASHINGTON (Feb. 21, 2018) — Post-traumatic stress disorder (PTSD) has long been attributed to members of the military following time in war. However, the disorder is also a prevalent problem emerging in civilians who experience high-stress situations. Researchers at the George Washington University (GW) have begun to explore the psychological components of anxiety disorders, such as PTSD, in assessing a possible connection between high stress and cardiovascular disease.
The National Institutes of Health recently awarded Paul Marvar, PhD, assistant professor of pharmacology and physiology at the GW School of Medicine and Health Sciences, more than $1.5 million to study the underlying mechanisms that allow the brain renin-angiotensin system to impact fear memory.
“Clinical evidence over the last 20 years has shown a link between individuals with post-traumatic stress and their incidence of cardiovascular disease, including coronary artery disease, atherosclerosis, and high blood pressure,” Marvar said. “Our research will look specifically at the brain renin-angiotensin system and its role in this connection.”
The brain renin-angiotensin system is involved in the regulation of blood pressure in part through neural control mechanisms that impact the kidneys and blood vessel function. Marvar believes that the angiotensin peptide and its receptors may also be a mediator in fear memory.
The renin angiotensin system has been widely implicated in cardiovascular disease and has also been identified in the stress response. In previous clinical research, Marvar and colleagues determined that individuals who were taking medications that block the angiotensin receptors, such as angiotensin-converting-enzyme inhibitors, or ACE inhibitors, had fewer PTSD symptoms.
Through this study, Marvar and his research team hopes to identify a particular mechanism to explain how the brain renin-angiotensin system may affect fear memory and associated increased risk of cardiovascular disease in PTSD.
“We think that if we are able to identify that, then we potentially will be able to intervene at different points following the traumatic memory,” he explained. “We could potentially use drugs that target the angiotensin system at the point of formation of the memory or extinction of the memory.”
This study will employ novel techniques using a highly sensitive form of mass spectrometry to look at how the peptides synthesize and identify the sites of action. Marvar is collaborating with Peter Nemes, PhD, associate professor of chemistry and biochemistry at the University of Maryland at College Park, an expert in mass spectrometry, whose research group recently developed an ultrasensitive mass spectrometer for neuroscience, critical to this research, with funding from the Arnold and Mabel Beckman Foundation.
The direction of the research is supported by ongoing clinical studies. The project titled, “Brain Angiotensin II as a Mediator of Fear Memory and Cardiovascular Dysfunction,” will be funded through 2021.
