National Institutes of Health Funds Colorado State University Study of Blood Flow and Oxygen Delivery

Colorado State University recently received two National Institutes of Health grants totaling $2.18 million to study how blood flow and oxygen delivery to peripheral tissues are controlled within the body.

The studies, which will be conducted in the Human Cardiovascular Physiology Laboratory in the Department of Health and Exercise Science, are designed to understand how peripheral blood vessels dilate and contract during stress such as exercise and low oxygen situations. Blood vessel behavior ultimately determines blood flow and oxygen delivery to muscle tissue.

“Answering questions about how these fundamental responses are controlled in humans may help people with acute or chronic heart or vascular conditions,” said Frank Dinenno, principal investigator of both grants and a university Monfort professor. “If we can learn about and understand how blood vessels work under these types of conditions, then we can potentially figure out how to improve that function. Blood flow to peripheral tissues can directly impact muscle function, which impacts quality of life – particularly in older healthy and diseased humans.”

Dinenno’s previous research has already laid some groundwork in understanding how aging impacts blood flow and oxygen delivery in humans. One of the recently funded studies specifically looks at how aging and sleep apnea impact oxygen delivery to tissues when circulating oxygen levels are drastically reduced. Sleep apnea increases the risk of cardiovascular disease, and older people with sleep apnea face an even greater risk.

When young, healthy individuals take in less oxygen while breathing, most peripheral blood vessels respond by relaxing to increase the amount of blood delivered to tissue. However, Dinenno’s laboratory has preliminary evidence that the vascular systems of older individuals don’t respond normally. In some situations, their bodies may respond the opposite way and constrict blood vessels, which further reduces tissue oxygen supply. This abnormal response may lead to an elevated risk for cardiovascular disorders such as high blood pressure, heart attack and stroke.

The other NIH funded study will determine how adenosine triphosphate – called ATP, the body’s chemical that can cause blood vessels to dilate – works during exercise when demands for oxygen to muscles increases. These studies will help scientists gain a better understanding of how ATP causes blood vessels to relax and widen during exercise, which could have implications for diseased humans.

The Department of Health and Exercise Science is in the College of Applied Human Sciences at Colorado State.