Objective: To observe the effects of low power microwave radiation on lens hydration and lens epithelial cells in vitro, and detect the expression of PKC-alpha, c-fos and c-jun in lens epithelial cells.
Methods: Rabbit lens were exposed to microwave radiation with frequency of 2450 MHz and power density of 0.5, 2.0 and 5.0 mW/cm(2) in vitro. The hydration of lens was measured after 8 hours. Morphological changes of lens epithelial cells were observed using a phase-contrast microscope and Hoechst 33258 staining. Expression of PKC-alpha, c-fos and c-jun were analyzed using gel electrophoresis and western blot analysis.
Results: After 2.0 and 5.0 mW/cm(2) microwave radiation, the hydration of lens was increased compared to control groups (P<0.05), the shape of lens epithelial cells showed shrinking and disorder and cells nuclei appeared chromatin condensation. There was no change of lens and lens epithelial cells after 0.5 mW/cm(2) microwave radiation. The expression of PKC-alpha was significantly increased in cell membrane, however, decreased in cell cytoplasm after 2.0 mW/cm(2) microwave radiation for 2, 4, 6 and 8 hours. There was significantly increased expression of c-fos and c-jun protein compared with control groups (P<0.05, P<0.01).
Conclusion: Low power microwave radiation higher than 2.0 mW/cm(2) can activate PKC-alpha by increasing its expression in cell membrane, then induce high expression of c-fos and c-jun, which may relate to cellular signaling pathway of microwave radiation injury to lens and lens epithelial cells.