Figure 2: Effects of HT on PMA-induced intracellular ROS and mitochondrial superoxide production. HUVEC were pretreated with HT (1–30 μmol/L) or vehicle (control, CTR) for 1 h and loaded by CM-H2DCFDA or MitoSOX Red as described in Materials and Methods, then stimulated with 10 nmol/L PMA for 16 h (a, b) and for the indicated times (c, d), and next fluorescence levels were evaluated by a fluorescence plate reader (a), fluorescence microscope (b), or fluorimeter (c, d). Data represent three independent experiments performed in triplicate and are expressed as means ± SD. versus CTR; versus PMA alone.