AzTrials
AzTrials

Endothelial DysfunctionNCT00845169

The Role of Nitric Oxide Synthase Isoforms in the Cardiovascular Effects of Air Pollution

A study testing Forearm vascular study in people with Endothelial Dysfunction, run by University of Edinburgh at 1 site in Sweden.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial summary

Exposure to air pollution has been linked to increased cardiorespiratory morbidity and mortality. The exact component of air pollution that mediates this effect is unknown, but the link is strongest for fine combustion derived particulate matter derived from traffic sources. Read more about this study

Who is it for?
Ages 18 to 40 yearsHealthy volunteers can take part
Conditions the study is for
Endothelial Dysfunction
What is being tested?
Forearm vascular study
Could I receive a placebo?
No, everyone receives an active treatment
How many people
16 participants
Where
1 siteSweden
Study dates
Apr 2012to Jun 2013
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 40 years
  • All sexes
  • Healthy volunteers accepted
  • Adult

Who may be able to join

  • Healthy volunteers

Who cannot join

  • Regular medication use (except oral contraceptive pill)
  • Current smokers
  • Significant occupational exposure to air pollution
  • Intercurrent illness

Trial locations and contacts

1 site in 1 country.

Sweden1 site
  • Umeå University

    Umeå

Other trials in Sweden

About this study

Exposure to air pollution has been linked to increased cardiorespiratory morbidity and mortality. The exact component of air pollution that mediates this effect is unknown, but the link is strongest for fine combustion derived particulate matter derived from traffic sources. Recently, it has been demonstrated that inhalation of diesel exhaust impairs vascular vasomotor tone and endogenous fibrinolysis. The mechanism underlying these detrimental vascular is unclear, but is thought to be via oxidative stress and altered bioavailability of endogenous nitric oxide. In these studies we plan to elucidate the role of endogenous nitric oxide synthase isoforms (NO) in the adverse vascular responses observed following exposure to diesel exhaust.

Being tested
Forearm vascular study
Keywords
Air Pollution, Nitric Oxide, Nitric Oxide Synthase, Diesel exhaust, endothelial dysfunction

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Forearm vascular studyProcedure or surgery

    Also called 1400W, SMTC, L-NMMA, Noreadrenaline

    Forearm venous occlusion plethysmography to measure forearm blood flow during intrabrachial infusion of nitric oxide synthase inhibitors L-NMMA (2-8 µg/min), S-methionyl-L-citrulline (25-200 nmol/min) and 1400W (100-1000 nmol/min) and positive control norepinephrine (60-540 pmol/min)

Study groups in NCT00845169
Study groupRoleWhat they receive
Diesel ExposureExperimental1 hour exposure to diesel exhaust at 300 µg/m3 during intermittent exercise
Receives: Procedure: Forearm vascular study
Air ExposureExperimental1 hour exposure to filtered air during intermittent exercise
Receives: Procedure: Forearm vascular study

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Forearm blood flow measured by venous occlusion plethysmography during intraarterial infusion of nitric oxide synthase inhibitors L-NMMA, SMTC and 1400W and positive control norepinephrine.

    Measured: 2-4 hours after exposure

Secondary outcomes (1)
  1. Plasma nitrite concentration

    Measured: During forearm study

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted18 Feb 2009 (estimated)
  2. Study startApr 2012
  3. Primary completionJun 2013
  4. Study completionJun 2013

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Basic science
Allocation
Randomised
Intervention model
Crossover
Masking
Triple blind
Who is masked
Participant, Investigator, Outcomes assessor
Enrolment
16 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT00845169
Sponsor's protocol ID
DNR 08-185M/2
Status last verified
Dec 2014
First submitted
17 Feb 2009
Last updated
2 Dec 2014
Results posted
No
Data monitoring committee
No

Questions about this trial

What is this clinical trial studying?

A study testing Forearm vascular study in people with Endothelial Dysfunction, run by University of Edinburgh at 1 site in Sweden.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 1 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 2 Dec 2014. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Sweden. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Forearm blood flow measured by venous occlusion plethysmography during intraarterial infusion of nitric oxide synthase inhibitors L-NMMA, SMTC and 1400W and positive control norepinephrine. (time frame: 2-4 hours after exposure). It is what the study was designed to measure, not a finding.

Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Dec 2014.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in