Examining how COX blockade affects blood pressure and vein size

Autonomic Control of the Circulation and the Venous Distension Reflex

Early Phase 1 Interventional Milton S. Hershey Medical Center · NCT03513770

This study is testing if a pain medication affects blood pressure and vein size in people during a specific blood flow test.

Quick facts

PhaseEarly Phase 1
Study typeInterventional
Enrollment18 (estimated)
Ages21 Years to 35 Years
SexAll
SponsorMilton S. Hershey Medical Center Academic / other
Locations1 site (Hershey, Pennsylvania)
Trial IDNCT03513770 on ClinicalTrials.gov

What this trial studies

This study investigates the mechanisms of the venous distension reflex (VDR) in humans by examining the effects of COX blockade using ketorolac tromethamine on muscle sympathetic nerve activity (MSNA) and vein size during venous distension. Participants will undergo wrist-to-elbow occlusion and receive either ketorolac or saline in a controlled setting. Measurements will be taken using 3T MRI to assess changes in vein size and MSNA response. Each subject will serve as their own control to enhance the reliability of the results.

Who should consider this trial

Good fit: Ideal candidates are healthy adults aged 21 to 35 who are free of chronic medical conditions.

Not a fit: Patients with chronic diseases or those taking medications affecting the cardiovascular or nervous system may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved understanding and management of blood pressure regulation in patients.

How similar studies have performed: While this approach is novel in its specific focus, similar studies have shown promise in understanding vascular responses to interventions.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria

* Are capable of giving informed consent
* Are any race or ethnicity
* Are fluent in written and spoken English
* Have a satisfactory history and physical exam to meet inclusion/exclusion criteria
* Are free of acute or chronic medical conditions
* Are 21 - 35 years of age (inclusive)
* Weigh over 50 kg

Exclusion Criteria

* Are less than 21 or over 35 years of age
* Are Pregnant or nursing women
* Are prisoners or institutionalized individuals or unable to consent
* Any chronic diseases (hypertension, heart, lung, neuromuscular disease, kidney disease, diabetes or cancer).
* Are taking medications that may affect their cardiovascular or nervous system
* Has taken an NSAID within 48 hours of any visit (visit will need to be rescheduled)
* Has never taken NSAIDs and therefore would not know if they are allergic to it
* Have a supine BP \>140/90 mmHg
* Have known allergy to ibuprofen-like drugs (NSAIDS) or aspirin
* Have history of asthma or nasal polyps
* Have history of GI bleeding or ulcers
* Subjects with ferromagnetic metal implants
* Subjects who are claustrophobic

Where this trial is running

Hershey, Pennsylvania

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Venous Distension ReflexBlood Pressure
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.