Enhancement by Hydrogen Peroxide of Calcium Signals in Endothelial Cells Induced by 5-HT1B and 5-HT2B Receptor Agonists

<div>(a) Effect of the agonists on [Ca<sup>2+</sup>]<sub>i</sub> in HUVEC in the absence and presence of H<sub>2</sub>O<sub>2</sub>. (b) Kinetics of calcium response to 5-HT in the absence and presence of H<sub>2</sub>O<sub>2</sub>. Concentration of H<sub>2</sub>O<sub>2</sub> was 100 <i>μ</i>M. Grey arrow indicates addition of H<sub>2</sub>O<sub>2</sub> or vehicle. Concentrations of the agonists were 5 <i>μ</i>g/mL for SFLLRN, 10<sup>-7</sup> M for bradykinin, and 10<sup>-5</sup> M for histamine, 5-HT, carbachol, or ADP. 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Oxidative Medicine and Cellular Longevity

fig1

Figure 1

Figure 1: Enhancement by Hydrogen Peroxide of Calcium Signals in Endothelial Cells Induced by 5-HT1B and 5-HT2B Receptor Agonists 