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NCT Number: NCT06499844

Comparing Approaches to Assess Nitric Oxide-dependent Cutaneous Vasodilation

The increase in skin blood flow in response to rapid local heating of the skin (i.e., cutaneous vasodilation) is commonly used to assess nitric oxide (NO)-dependent dilation and overall microvascular function. Historically, rapid local heating to 42°C was considered the standard approach for these assessments. More recently, many investigators have adopted rapid local to 39°C instead, based on its larger dependency on NO and therefore improved ability to quantify NO-dependent dilation without the use of pharmacological techniques. However, to date, only one direct methodological comparison between these protocols has been performed.

In this study, the investigators use the blood vessels in the skin as a representative vascular bed for examining mechanisms of microvascular dysfunction in humans. Using a minimally invasive technique (intradermal microdialysis for the local delivery of pharmaceutical agents) they examine the blood vessels in a nickel-sized area of the skin in young adults ages 18 - 30 years old. Local heating of the skin at the microdialysis sites is used to explore differences in mechanisms governing microvascular control. As a compliment to these measurements, the investigators also have participants fill out a variety of surveys to assess things such as sleep quality, physical activity, daily stressors, etc.

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Key information

Conditions

Endothelial Function

Age range

18 year–30 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Early Phase 1

Primary location

University of Iowa

Iowa City, Iowa, 52242, United States

Location status: Recruiting

Location contact

Anna Stanhewicz, PhD

CONTACT

[email protected]

319-467-1732

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • men and women
  • 18-30 years of age

Exclusion criteria

  • Current or recent (within 8 wks) use of medication that could conceivably alter microvascular function [including (but not limited to) stimulants, antihypertensives, HMG-CoA reductase inhibitors]
  • Changes or alterations in medication status (starting a new, additional, or different medication or changing the dose of a current medication)
  • Unstable or diagnosed chronic clinical disease, including cardiovascular, metabolic, renal, hepatic, autonomic, autoimmune, or dermatological disease (e.g., hypertension, heart disease, diabetes, hyperlipidemia, psoriasis)
  • Body mass index <18.5 or >35 kg/m2
  • Pregnancy (including a positive urine pregnancy test) or breast-feeding
  • Known allergies to pharmacological agents or study drugs
  • Non-English-speaking. Participants need to understand English to follow instructions and comply with procedures conducted during the screening and experimental visits.

Treatment and study plan

Acetylcholine

Drug

acetylcholine, and acetylcholine + L-NAME (Nitric oxide synthase inhibitor) are locally and acutely delivered to the cutaneous microvasculature to assess endothelium- and nitric oxide-dependent dilation

Primary outcomes

  1. Microvascular blood flow response to acetylcholine

    Time frame: baseline study visit (average of 4 hours)

    cutaneous vascular vasodilator response to exogenous acetylcholine perfusion; measured with laser-Doppler flowmetry coupled with intradermal microdialysis delivery of acetylcholine alone or co-infused with L-NAME

  2. Microvascular blood flow response to local heat (42 degrees Celsius)

    Time frame: baseline study visit (average of 4 hours)

    cutaneous vascular vasodilator response to 42 degree local heat; measured with laser-Doppler flowmetry coupled with intradermal microdialysis delivery of lactated Ringer's, followed by L-NAME.

  3. Microvascular blood flow response to local heat (39 degrees Celsius)

    Time frame: baseline study visit (average of 4 hours)

    cutaneous vascular vasodilator response to 39 degree local heat; measured with laser-Doppler flowmetry coupled with intradermal microdialysis delivery of lactated Ringer's, followed by L-NAME.

Study contacts

Contact information is provided by the study sponsor or research team.

Anna Stanhewicz, PhD

CONTACT

[email protected]

3194671732

Sponsors and collaborators

Lead sponsor

University of Iowa

Other

Registry information

Acronym: CAP NOVA

Important dates

Study start
2024
Primary completion
2025
Study completion
2026
First posted
Jul 15, 2024
Registry last updated
Aug 24, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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