Fig. 2.

Cx43 expression is decreased by oxidants. MLO-Y4 cells were treated with (A) 0.1, 1, 2, 5, 10 or 20 µM of rotenone for 16 hrs or (B) 20 µM of menadione for 7 hrs. Cell lysate was immunoblotted with Cx43(E2) or β actin antibody. Lower panels of (A) and (B) show the ratios of band intensities of Cx43 to β-actin (n = 3). Control versus 1 µM rotenone, **, P < 0.01; control versus 2, 5, 10 and 20 µM rotenone, ***, P < 0.001. Control versus 20 µM menadione, *, P < 0.05. (C) MLO-Y4 cells were treated with 20 µM menadione for 24 hrs after which cells were trypsinized, incubated with annexin V-FITC and PI and subjected to flow cytometry.