Recruiting
Early Phase 1

Observational Study

Sponsor:

University of Missouri-Columbia

Code:

NCT05219799

Conditions

Obesity

Vasodilation

Healthy

Eligibility Criteria

Sex: All

Age: 18 - 45

Healthy Volunteers: Accepted

Interventions

Propranolol Hydrochloride

Isoproterenol

Phentolamine Mesylate

Norepinephrine

Study Details

Brief summary:

The purpose of this project is to examine key mechanisms contributing to sex-differences in hypoxic vasodilation and the impact of obesity, with particular emphasis on the sympathetic nervous system.

Conditions

Obesity

Vasodilation

Healthy

Study ID

NCT05219799

Start date

Mar 14, 2023

Status verified date

Jul, 2026

Completion date

Jul 30, 2027

Anticipated

Primary completion date

Jul 30, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 45

Healthy Volunteers: Accepted

Inclusion Criteria:

  • BMI >18 kg/m2

Exclusion Criteria:

  • Pregnancy, breastfeeding
  • Diagnosed sleep apnea or AHI >10 events/hr
  • Current smoking/Nicotine use
  • Increased risk of bleeding, pro-coagulant disorders, clotting disorders, anticoagulation therapy
  • Nerve/neurologic disease
  • Cardiovascular, hepatic, renal, respiratory disease
  • Blood pressure ≥140/90 mmHg
  • Diabetes, Polycystic ovarian syndrome
  • Communication barriers
  • Prescription medications, Sensitivity to lidocaine

Study Design

Enrollment

72 participants

Anticipated

Intervention Model

Single group

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

other: Hypoxia Exposure

Men and women will be exposed to isocapnic hypoxia. Participants will wear a mask and systemic oxygen levels will be titrated to attain hypoxemia as assessed by pulse oximetry.

Interventions

Propranolol Hydrochloride

Regional forearm blockade of β-adrenergic receptors at 20 mcg/dL/min via brachial artery catheter during normoxia and hypoxia exposures

Isoproterenol

Dose response (1, 3, 6, and 12 ng/dL/min) regional infusion to assess β-adrenergic receptor responsiveness

Phentolamine Mesylate

This infusion will be for 10 min before baseline measurement (12 mcg/dL/min) and continue the infusion at a maintenance rate (5 mcg/dL/min).

Norepinephrine

Regional forearm infusion at 8 ng/dL/min via brachial artery catheter during normoxia and hypoxia exposures

Primary outcome measure

  • Change in forearm vascular conductance with intra-arterial drug infusion [ Time Frame: Change from baseline to last 1-minute of drug infusion ]

Central Contacts and Locations

Central contacts

Jacqueline K Limberg, Ph.D.

5738822544limbergj@missouri.edu

Locations

University of Missouri

Recruiting

Columbia, Missouri, United States, 65211

Contacts

Jennifer L Harper

5738822544harperjl@missouri.edu

More Information

Sponsor

University of Missouri-Columbia

Last update posted

Jul 28, 2026

Last verified

Jul, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by University of Missouri-Columbia on 2026-07-28.