Brain Blood Vessel Responses to Changes in Blood Flow: Younger Cohort
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: MRI, Prazosin, Placebo.
- Who it may be relevant to
- Registry conditions: Magnetic Resonance Imaging, Cerebrovascular Circulation. Basic parameters: 20 years — 40 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- United States
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Cerebrovascular Responses to Acute Hypoperfusion
Overview
Brain blood flow will be measured during a simulated postural change test and while breathing increased levels of carbon dioxide using magnetic resonance imaging.
Detailed description
Global cerebral blood flow (CBF) decreases with advancing age; however, some adults have accelerated declines in CBF, placing them at a greater risk of cognitive impairment. However, there is a lack of human studies that investigate the cause or consequence of altered blood flow regulation in the brain. This study will systematically address this gap in knowledge by examining cerebrovascular control in adults during acute physiological challenges (simulated postural change test and breathing increased carbon dioxide) that stimulate a change in CBF.
Interventions
- Device MRI
Participants will undergo an MRI scan while performing breathing and simulated postural change tasks. - Drug Prazosin
A dose of prazosin will be administered based on body weight - Drug Placebo
Oral placebo
Primary outcome measures
- Change in blood velocity [Time frame: Two study visits, up to 240 minutes]
- Change in blood flow [Time frame: Two study visits, up to 240 minutes]
Eligibility criteria
Inclusion criteria
- Between the ages of 20-40 years
- Have a BMI ≤34.5 kg/m2
- are less than 72 in (182.88 cm) height
- Nonsmoker
Exclusion criteria
- Diagnosis of Mild Cognitive Impairment (MCI) or Alzheimer's disease (AD)
- History or evidence of hepatic disease, hematological disease, or peripheral vascular disease; severe kidney injury requiring hemodialysis
- History of cardiovascular disease including: severe congestive heart failure, coronary artery disease, ischemic heart disease (stents, coronary artery bypass grafts) and tachycardia
- Uncontrolled hypertension
- History of clinically significant ischemic or hemorrhagic stroke, or significant cerebrovascular disease
- Severe untreated obstructive sleep apnea
- History of diabetes with HbA1c greater than 9.5 percent
- Major neurologic disorders other than dementia (e.g., MS, ALS, brain surgery, etc.)
- Current or recent (less than1 year) major psychiatric condition (Axis I) or addictive disorders
- Significant surgical history
- Other significant medical conditions at investigators' discretion
- Contraindications to MRI
- Prescribed medications that interfere with prazosin
- Lactose allergy
- lower body will not fit in lower body negative pressure (LBNP) chamber (regardless of overall height and BMI)
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: Yes
Study design
- Allocation
- N/A
- Model
- Single group
- Masking
- Open label
- Primary purpose
- Basic science
Study locations
United States · 1 center
- University of Wisconsin — Madison
Identifiers
NCT: NCT06629090 · 2024-0377: Younger Cohort · A176000 · EDUC/KINESIOLOGY · Protocol Version 7/29/2025