[Comparison between two methods for staining DNA of apoptotic spermatozoa].

OBJECTIVE

To compare two fluorochrome staining methods for the assessment of sperm quality.

METHODS

Washed sperm cells were incubated in 0, 0.15, or 15 micromol/L camptothecin (CAM), or 0.37 or 3.7 mmol/L genistein (GEN) at 37 degrees C for 4 hours. The sperm cells were analyzed for cycle-independent apoptosis and necrosis by single-stain compared with dual-stain fluorescence microscopy to contrast the relative effectiveness of these two approaches.

RESULTS

The single-stain procedure could not detect the sperm viability differences. In contrast, the dual-stain procedure identified a dosage-dependent decrease in the viability and increased necrozoospermia after topoisomerase inhibitor CAM and GEN treatments. Apoptosis was 2-fold higher with topoisomerase inhibitor treatment.

CONCLUSION

The two topoisomerase inhibitors were associated with increased apoptosis and dosage-dependent necrosis. The data suggested that the dual-stain combination Hoechst 33342/PI was more sensitive than the single Hoechst 33342 stain analysis and permitted quantitative analysis of the apoptosis and necrosis in sperm.