How younger adults' brain blood vessels respond to changes in blood flow

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This Phase 2 interventional protocol uses MRI to measure global cerebral blood flow in adults aged 20–40 during two controlled physiological challenges: a simulated postural change (via lower body negative pressure) and controlled increases in inhaled carbon dioxide. Participants will receive prazosin or placebo and undergo MRI scans while investigators record cerebrovascular responses and blood flow regulation. The trial excludes people with major cardiovascular, cerebrovascular, neurologic, psychiatric, hepatic, or renal disease, as well as smokers and those outside the specified BMI and height limits. Data will compare responses with and without alpha‑1 blockade to clarify mechanisms of cerebrovascular control that could relate to later cognitive risk.

Why it matters

Who can join: the full rules

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)

Where it's running

• University of Wisconsin
  Madison, Wisconsin, United States Recruiting

Study contacts

• Principal investigator: Jill Barnes, PhD — UW Madison
• Study coordinator: Anna Howery
• Email: ahowery@wisc.edu
• Phone: 608-262-9572

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.