The Cardiovascular Effects of Nitrogen Dioxide Exposure

NCT ID: NCT00774514

Last Updated: 2009-04-09

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 12 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2008-10-31
• Study Completion Date: 2008-12-31

Brief 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. It has been demonstrated that inhalation of diesel exhaust impairs vascular vasomotor tone and endogenous fibrinolysis. Recent studies using an inline retrofit particle trap to reduce the particulate component of exhaust have shown that filtering particles leads to a reversal of the endothelial dysfunction seen after diesel exhaust exposure, and have even suggested an augmentation of vascular function. This raises the question of the cardiovascular effects of the gaseous pollutants, the most abundant of which is nitrogen dioxide. In this study we plan to investigate the cardiovascular effects of nitrogen dioxide exposure.

Conditions

Endothelial Dysfunction

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: CROSSOVER
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: TRIPLE

Study Groups

Air exposure

1 hour exposure to filtered air during intermittent exercise

Group Type: EXPERIMENTAL

Forearm Vascular Study

Intervention Type: PROCEDURE

Forearm venous occlusion plethysmography to measure forearm blood flow during intrabrachial infusion of vasodilators Acetylcholine (5-20 mg/min), sodium nitroprusside (2-8 µg/min), bradykinin (100-1000 pmol/min) and verapamil (10-100 µg/min)

NO2 exposure

1 hour exposure to nitrogen dioxide at 4ppm during intermittent exercise

Group Type: EXPERIMENTAL

Forearm Vascular Study

Intervention Type: PROCEDURE

Forearm venous occlusion plethysmography to measure forearm blood flow during intrabrachial infusion of vasodilators Acetylcholine (5-20 mg/min), sodium nitroprusside (2-8 µg/min), bradykinin (100-1000 pmol/min) and verapamil (10-100 µg/min)

Interventions

Forearm Vascular Study

Forearm venous occlusion plethysmography to measure forearm blood flow during intrabrachial infusion of vasodilators Acetylcholine (5-20 mg/min), sodium nitroprusside (2-8 µg/min), bradykinin (100-1000 pmol/min) and verapamil (10-100 µg/min)

Intervention Type: PROCEDURE

Other Intervention Names

ACh; SNP; BK

Eligibility Criteria

Inclusion Criteria

• Healthy male volunteers

Exclusion Criteria

• Current smokers
• Significant occupational exposure to air pollution
• Regular medication use
• Intercurrent illness

• Eligible Sex: MALE
• Accepts Healthy Volunteers: Yes

Sponsors

Umeå University

OTHER

Sponsor Role: collaborator

University of Edinburgh

OTHER

Sponsor Role: lead

Responsible Party

Umeå University

Principal Investigators

Thomas Sandström, MD PhD

Role: PRINCIPAL_INVESTIGATOR

Umeå University

Anders Blomberg, MD PhD

Role: PRINCIPAL_INVESTIGATOR

Umeå University

Locations

Umeå University

Umeå, , Sweden

Countries

Sweden

Other Identifiers

Dnr 08-113M

Identifier Type: -

Identifier Source: org_study_id