title: [Oxidative stress in nitroglycerin tolerance and treatment with 3,4,5,6-tetrahydroxyxanthone].
abstract: 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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Cardiology, Xiangya Hospital, Central South University, Changsha 410008, China.
authors.forename: Rui-zheng
authors.initials: RZ
authors.lastname: Shi
authors.forename: Guo-gang
authors.initials: GG
authors.lastname: Zhang
authors.forename: Yong-ping
authors.initials: YP
authors.lastname: Bai
authors.forename: Yuan-jian
authors.initials: YJ
authors.lastname: Li
authors.forename: Gao-yun
authors.initials: GY
authors.lastname: Hu
authors.forename: Jia
authors.initials: J
authors.lastname: Chen
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001013:Aorta, Thoracic / Q000166:cytology; D002478:Cells, Cultured; D004361:Drug Tolerance; D004730:Endothelium, Vascular / Q000166:cytology*; D006801:Humans; D008297:Male; D005996:Nitroglycerin / Q000494:pharmacology*; D018384:Oxidative Stress; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism; D014471:Umbilical Veins / Q000166:cytology; D044004:Xanthones / Q000494:pharmacology*
chemical_list: C518384:3,4,5,6-tetrahydroxyxanthone; D000975:Antioxidants; D017382:Reactive Oxygen Species; D044004:Xanthones; D005996:Nitroglycerin