Figure 7.

H1R overexpression enhances histamine-stimulated H₂O₂ production in Duox/DuoxA-expressing HEK-293 cells. (A) HEK-293 cells stably expressing the Duox1/DuoxA1α (D1A1α) or the Duox2/DuoxA2 (D2A2) system were transiently transfected with a plasmid coding the H1R or a with green fluorescent protein (GFP)-expressing plasmid (control). H₂O₂ production stimulated by histamine (100 μM) was measured 2 days after transfection by homovanillic acid/horseradish peroxidase assay (values are normalized on unstimulated GFP-expressing cells). Mean ± SEM of three independent experiments is shown. (B) H1R expression in cell lysates of nontransfected HEK-293 cells or cells transiently transfected with the H1R-coding plasmid was assessed by Western blotting using an anti-H1R antibody. One representative experiment is shown.