Objective: To determine the relationship between the nitroglycerin tolerance and the stimulation of radical oxygen species (ROS) production, and the therapeutical effect of 3,4,5,6-tetrahydroxyxanthone.
Methods: Vasodilator responses to nitroglycerin were examined in the isolated thoracic aorta. The contents of ROS,and cGMP were determined in the cultured human umbilical vein endothelial cells.
Results: 3,4,5,6-tetrahydroxyxanthone could significantly reduce the inhibition of relaxation by nitroglycerin. 3,4,5,6-tetrahydroxyxanthone could significantly inhibit the ROS increase and increase the cGMP level.
Conclusion: Nitroglycerin tolerance is associated with the stimulation of ROS production,and the reversal of nitroglycerin tolerance with 3,4,5,6-tetrahydroxyxanthone is related to the reduction of ROS.