Official Title: “The Effect of a Retrofit Particle Trap on the Vascular Effects of Diesel Exhaust Inhalation”

The purpose of this study is to determine whether a retrofit particle trap can reduce the adverse vascular responses to diesel exhaust inhalation

Study Type: Interventional

Study Design: Basic Science, Randomized, Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Crossover Assignment

Study Primary Completion Date: February 2008

18 subjects healthy male volunteers will be recruited at Umeå University. In a randomised, double blind 3 way crossover trial, subjects will be exposed to filtered air, diesel exhaust (300mcg/m3) or filtered diesel exhaust for 1 hour during intermittent exercise.

2 hours following the exposure, thrombogenicity will be assessed using the Badimon chamber - an ex-vivo model of thrombosis formed under constant flow conditions.

Forearm blood flow in response to infused intra-brachial vasodilators will be measured using venous occlusion plethysmography 6 hours after the exposure.

Arterial stiffness will be measured using peripheral arterial applanation tonometry in the hour post-exposure.

Blood samples will be collected at timepoints over the 24 hours after exposure.

Intervention(s) in this Clinical Trial

• Procedure: Forearm Venous Occlusion Plethysmography
  • Forearm venous occlusion plethysmography with intra-arterial infusion of Acetylcholine (5-20mcg/min), bradykinin (30-300mcg/min), sodium nitroprusside (2-8mcg/min) and Verapamil (2-10 mcg/min) into non-dominant brachial artery

Arms, Groups and Cohorts in this Clinical Trial

• Experimental: 1
  • 1 hour exposure to filtered air
• Experimental: 2
  • 1 hour exposure to diesel exhaust (300mcg/m3)
• Experimental: 3
  • 1 hour exposure to filtered diesel exhaust

Primary Measures

• Forearm blood flow in response to infused intra-arterial vasodilators
  • Time Frame: 6 hours post-exposure
    Safety Issue?: No

Secondary Measures

• Arterial stiffness measured by applanation tonometry
  • Time Frame: In the 1 hour following exposure
    Safety Issue?: No
• Thrombogenicity measured using the Badimon chamber - an ex-vivo model of thrombosis under conditions of continuous flow
  • Time Frame: 2 hours after the exposure
    Safety Issue?: No
• Exhaled nitric oxide - a marker of pulmonary inflammation
  • Time Frame: 1 hour & 6 hours after exposure
    Safety Issue?: No
• Endogenous fibrinolytic capacity - measured as net release of t-PA in response to infused bradykinin
  • Time Frame: 6 hours after exposure
    Safety Issue?: No
• Biochemical markers of systemic inflammation
  • Time Frame: Baseline, 2, 6 & 24 hours
    Safety Issue?: No

Inclusion Criteria:

• Healthy male volunteers

Exclusion Criteria:

• Intercurrent illness
• Smoking
• Significant occupational exposure to air pollution
• Regular medication usage

Gender Eligibility for this Clinical Trial: Male

Minimum Age for this Clinical Trial: 18 Years

Maximum Age for this Clinical Trial: 35 Years

Are Healthy Volunteers Accepted for this Clinical Trial?: Accepts Healthy Volunteers

Lead Sponsor: University of Edinburgh

Overall Clinical Trial Officials and Contacts

Anders Blomberg, MD Principal Investigator Umeå University  

Information obtained from ClinicalTrials.gov on July 02, 2009

Link to the current ClinicalTrials.gov record. http://clinicaltrials.gov/show/NCT00745446

Study ID Number: VOLVO 3ARM

ClinicalTrials.gov Identifier: NCT00745446

Health Authority: Sweden: Regional Ethical Review Board