Norepinephrine Induces Lung Microvascular Endothelial Cell Death by NADPH Oxidase-Dependent Activation of Caspase-3

Figure 1

Norepinephrine induces ROS production in rat lung microvascular endothelial cells. Rat lung microvascular endothelial cells (RLMEC) were stimulated with norepinephrine (NE) 5 ng/mL for 120 minutes. (a) NE increases ROS production in RLMEC, an effect inhibited in the presence of PEG-SOD. (b) ROS levels are decreased in the presence of PEG-CAT. (c) Comparative graph illustrating the effects of PEG-SOD and PEG-CAT on ROS production stimulated by the exposure of RLMEC to NE for 5 minutes. (d) Representative images of ROS production by NE in RLMEC assessed by DCF fluorescence; effects of PEG-SOD and PEG-catalase are also shown. (e) Quantification of ROS production assessed by DCF fluorescence: RLMEC were stimulated with NE 5 ng/mL for 15 min in the presence and absence of PEG-SOD and PEG-CAT. (f) Phentolamine (Phen) and propranolol (Prop) had no effects on basal ROS production; Phen inhibited NE-induced ROS production in RLMEC and Prop partly inhibited NE-induced ROS production on RLMEC. vs. control, vs. NE, vs. NE+PEG-SOD, vs. propranolol. /group.

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