Effect of Nitric Oxide Donor on Endothelial Progenitor Cells in Patients With Coronary Artery Disease
Status:
Completed
Trial end date:
2005-09-01
Target enrollment:
Participant gender:
Summary
Regular exercise reduces the risk of heart problems, in part because it improves the work of
the endothelium (the cells that line blood vessels). Exercise appears to release precursor
cells from the bone marrow that will later become endothelial cells. A molecule called nitric
oxide (NO) appears to be involved in this release. However, some heart patients do not
improve their endothelial function despite regular exercise. The researchers believe that the
heart disease in these patients may interfere with the normal relationship between exercise
and endothelial function. This study is designed to test whether giving a patient
nitroglycerin (which is converted to NO in the bloodstream) will increase the release of
endothelial precursor cells from the bone marrow. If the study succeeds, it may lead to
improved healing of arteries in heart disease patients.
Adults may be eligible for this study if they have coronary artery disease and do not take
nitroglycerin or nitroglycerin-like medication on a daily basis.
Volunteers will be admitted to the Clinical Center on 2 separate nights at least 1 week
apart. On the morning after each admission, volunteers will have blood drawn from an arm vein
for laboratory tests, and then walk on a treadmill until fatigue or discomfort prevents
further exercise, or until asked to stop. On one of their admissions, volunteers will receive
1 tablet of nitroglycerin under the tongue shortly before the treadmill test. Volunteers will
be monitored by EKGs and blood pressure tests during the treadmill tests, and will have more
blood drawn at about 15 minutes and 24 hours after each treadmill test. Researchers will
examine the levels of endothelial precursor cells and nitric oxide in the blood samples taken
before and after exercise.