Figure 4.

The expression of Bax (A) increased, whereas Bcl-2 (B) decreased, as shown by immunocytochemistry in differentiated PC12 cells 6 h after 30 mW/cm² microwave exposure. All immunoblotting analyses (C), except detection of cytochrome c, were performed using whole cell lysates. After sucrose gradient centrifugation, the supernatant was used as the cytosolic fraction for cytochrome c detection. The immunoblotting results further confirmed the up-regulation of Bax, cytochrome c, cleaved caspase-3 and PARP, and the down-regulation of Bcl-2. Caspase-3 activity (D) also increased, as assessed by ELISA. Moreover, the caspase-3 inhibitor DEVD significantly inhibited the increase of cleaved caspase-3, PARP (C) and caspase-3 activity (D) induced by microwave exposure. Significant differences are as follows: vs. control, **p < 0.01 (t test). Scale bars: 50 µm.