Tetramethylpyrazine Protects against Hydrogen Peroxide-Provoked Endothelial Dysfunction in Isolated Rat Aortic Rings: Implications for Antioxidant Therapy of Vascular Diseases
Figure 4
Tetramethylpyrazine (TMP), apocynin, diphenyleneiodonium (DPI), and Tiron prevent hydrogen peroxide- (H2O2-) induced production of the superoxide anion () in primary rat aortic endothelial cells. production was detected by the dihydroethidium- (DHE-) mediated fluorescence microscopy assay. Cells were treated with H2O2 (200 μM) alone or in combination with TMP (10 nM), apocynin (10 μM), DPI (10 nM), or Tiron (10 nM) plus diethyldithiocarbamic acid (DETCA) (1 mM) pretreatment. The bar graph shows the fluorescence intensity (%) of each experimental group relative to the control. Data represent the mean ± the standard error of the mean (SEM) of 3–9 independent experiments ( versus control; versus H2O2).
