Effects of NO content on apoptosis of spermatogenic cells in male infertile cases

    YU Aiª²Lian£¬LIU Yaª²Ling£¬ZHANG Fengª²Xue£¬LI Yaª²Lu, ZHAO Yingª²Hui

    Department of Etiology, Taishan Medical College£¬Tai¡¯an 271000£¬China

    ¡¾Abstract¡¿ AIM: To explore the roles of nitric oxide (NO) content in apoptosis of spermatogenic cells in male infertile cases. METHODS: NO concentration was tested by nitric acid reductase in 80 male infertile cases and 62 normal fertile men. Apoptosis of spermatogenic cells was examined by terminal deoxynucleotidyl transferase mediated deoxyuridine triphophateª²biotin nick end labeling (TUNEL) in 15 male infertile cases, 12 male infertile cases with level of NO over 135 ¦Ìmol/L and 15 normal fertile men. The ultrastructure of apoptotic spermatoª²genic cells was observed by electron microscopy. RESULTS: The NO concentration in semen was (107.8¡À25.9) and (76.5¡À16.4) ¦Ìmol/L in the 80 male infertile cases and the 62 normal fertile men respectively. There was significant difference between the two groups (P<0.01). The NO concentration was (76.7¡À10.4) ¦Ìmol/L and the apoptosis rate of spermatogenic cells was (3.8¡À1.3)% in 15 normal fertile men, while those of the 15 infertile cases were (112.7¡À14.3) ¦Ìmol/L and (4.7¡À1.9)% respectively. The apoptosis rate of spermatogenic cells was (16.3¡À4.0)% in 12 male infertile cases with NO level over 135 ¦Ìmol/L. The NO concentration and the apoptosis rate of spermatogenic cells in male infertile cases were higher than those of normal group (P<0.05). The apoptosis rate of spermatogenic cells in male infertile cases with NO level over 135 ¦Ìmol/L was significantly high than that in normal group (P<0.05) and other male infertile cases (P<0.01). Electron microscope showed that the spermatogenic cells had such changes as the concentration and increased electron density of the nuclear chromatin, the expansion and folding of the nuclear membrane, the decomposition of the nucleus, and the appearance of apoptotic bodies. CONCLUSION: Abnormal high levels of NO in semen result in the increased apoptosis of spermatogenic cells, which reduce fertility. ......