[A quantitative study on early changes in rabbit lens capsule epithelium induced by low power density microwave radiation].

OBJECTIVE

To test the safety of guidelines for limiting exposure to low power level microwave radiation and to try to explore the mechanisms of early damages induced by such radiation in rabbit lens capsule epithelial cells, using flow cytometry as a quantitative method of evaluation of these damages.

METHODS

The rabbit eyes were exposed to 5 mW/cm(2) (group I) and 10 mW/cm(2) (group II) power densities of microwave for 3 h. Annexin V-PI two-color flow cytometry was used to detect the changes of rabbits lens epithelial cells, apoptosis cells and secondary necrotic cells after radiation. The other eyes served as self-controls.

RESULTS

In group I, the percentage of early apoptosis cells in the experimental eyes was significantly greater than that of the controls (P < 0.01), whereas no significantly difference in the percentage of secondary necrotic cells could be observed (P > 0.05). In group II, there was no significant difference between the percentage of early apoptosis cells in experimental eyes and the controls (P > 0.05), whereas the percentage of secondary necrotic cells in the experimental eyes was significantly greater than that of the controls (P < 0.05). The percentage of secondary necrotic cells (16.2 +/- 5.6)% in group II is greater than that in group I (10.3 +/- 6.8)% (P < 0.05), though there is no significant difference in the percentage of early apoptosis cells between these two groups (P > 0.05).

CONCLUSION

Low power density of microwave radiation (5 mW/cm(2) and 10 mW/cm(2)) can induce irreversible damage of rabbit lens epithelial cells in a dose-dependent manner. Therefore, the safety dosage criterion of microwave exposure needs further investigation.