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

Endothelial Dysfunction Clinical Trial

Official title:

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

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00845169
• Other study ID #: DNR 08-185M/2
• Status: Completed
• Phase: N/A
• First received: February 17, 2009
• Last updated: December 1, 2014
• Start date: April 2012
• Est. completion date: June 2013

Study information

• Verified date: December 2014
• Source: University of Edinburgh
• Contact: n/a
• Is FDA regulated: No
• Health authority: Sweden: Regional Ethical Review Board
• Study type: Interventional

Clinical 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. 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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 16
• Est. completion date: June 2013
• Est. primary completion date: June 2013
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years to 40 Years

Eligibility

Inclusion Criteria:

• Healthy volunteers

Exclusion Criteria:

• Regular medication use (except oral contraceptive pill)

• Current smokers

• Significant occupational exposure to air pollution

• Intercurrent illness

Study Design

Allocation: Randomized, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Investigator, Outcomes Assessor), Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Endothelial Dysfunction

Intervention

Procedure:
• Forearm vascular study
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)

Locations

Country	Name	City	State
Sweden	Umeå University	Umeå

Sponsors (3)

Lead Sponsor	Collaborator
University of Edinburgh	NHS Lothian, Umeå University

Country where clinical trial is conducted

Sweden, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	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.		2-4 hours after exposure	No
Secondary	Plasma nitrite concentration		During forearm study	No