Cerebral vasodilator responses to CO2 will be measured in young healthy adults, healthy sedentary older adults, and healthy exercise trained older adults. This variable will be examined before and after administering the cyclooxygenase inhibitor indomethacin, which has been shown to blunt cerebral vasodilator responses. In addition, the investigators will examine these counter-regulatory hemodynamic mechanisms to hypoperfusion caused by indomethacin.
Normal aging reduces cerebral blood flow and cognitive function. Aging also appears to alter functional connectivity within the brain, which is associated with cognitive functioning. Observational studies suggest that regular physical activity is associated with higher cerebral blood flow and improved cognitive function. However, the mechanistic links among regular physical activity and cerebral blood flow with advancing age are unknown. In this context, it is unclear if aging or exercise training status alters the neurovascular coupling of blood flow in the brain. Thus, the overall goal of this study is to examine the age-related changes in cerebral vasodilatory capacity, an important homeostatic mechanism and marker for effective regulation of cerebral perfusion, in order to determine how it is mechanistically linked to cognition. Additionally, the investigators will explore the potential beneficial effect of physical activity on the relationships between cerebral vasodilation and cognition in humans. The research aims are: 1. To determine if cerebral vasodilator responses are affected by age and exercise training status in healthy adults. 2. To compare the effect of cyclooxygenase inhibition on cerebral vasodilator responses in healthy adults. 3. To determine the neurovascular counter-regulatory response to cyclooxygenase inhibition in healthy adults.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
OTHER
Masking
NONE
Enrollment
80
1. Transcranial Doppler 2. Blood Pressure 3. Heart Rate 4. Oxygen Saturation
1. Transcranial Doppler 2. Blood Pressure 3. Heart Rate 4. Oxygen Saturation
Gymnasium-Natatorium
Madison, Wisconsin, United States
Cerebral Vasodilator Responses
Utilize a Transcranial Doppler to measure blood flow velocity in response to inhaled carbon dioxide.
Time frame: Measurement at baseline
Cerebral Vasodilator Responses
Utilize a Transcranial Doppler to measure blood flow velocity in response to inhaled carbon dioxide.
Time frame: Measurement beginning 60 minutes post drug and measured through 180 minutes
Blood Pressure
Time frame: Measurement at baseline and beginning 60 minutes post drug and measured through 180 minutes
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.