RESUMO
Objective To investigate the correlation between sperm-nucleporotein transition and sperm parameters and embryo development,also to evaluate the influence of pregnancy out comes of assisted reproductive technology (ART).Methods Sperm-nucleoprotein transition assay of a total of 676 patients underwent ART treatment were detected by aniline blue staining,and the correlation analysis between spermnucleoprotein transition and sperm parameters,DNA damage,acrosin activity,fertilization rate,cleavage rate,quality of early embryo development as well as blastocyst formation rate was performed.Results The sperm concentration,(a+b) ％ sperm,sperm count and acrosin activity was (66.5±4.6) × 109/L,(149.2±9.9)×109/L,(51.2±1.3)％ and (72.2±3.3) mU/106 sperm in abnormal group,and (91.9±2.7) ×109/L,(240.0±8.0) ×109/L,(57.3±0.8)％ and (85.7±1.9) mU/106 sperm in normal group,which reached significant difference (P＜0.01).DNA fragmentation index (DFI) was (17.3± 1.0)％ in abnormal group,which was significantly higher than (14.6±0.5)％ in normal group.The cleavage rate of 95.0％,D3/D5 high quality embryo rates of 34.2％ and 1.28％,D5 blastocyst formation rate and the total rate of blastocyst formation rate of 22.4％ and 38.6％ in abnormal group,which were significantly lower than that in normal group (96.9％,38.2％,2.70％,27.9％ and 46.4％) (P＜0.01).The rate of spontaneous abortion was 12.3％ in abnormal group,which was significantly higher than that in normal group (4.7％) (P＜0.01).However,there was no significant difference in biochemical pregnancy rate and ectopic pregnancy rate between the 2 groups (P＞0.05).Conclusions Sperm-nucleoprotein transition was positively related with sperm parameters,DNA damage,acrosin activity,and also has an adverse effect on embryo development and the outcomes of ART.It is suggested that the sperm-nucleoprotein transition should be detected before ART.
RESUMO
During spermatogenesis, lysine-rich histones in spermatogenic cells are progressively replaced by arginine-rich protamine. In this study, the nucleoprotein transition in spermatogenic cells of Wistar rat was investigated using aniline blue staining, PTA staininig (both to demonstrate lysine-proteins) and NQS (1, 2-naphthoquinone4-sodium sulfonate) staining (to demonstrate arginine-protein). Under light microscope, the nuclei of spermatogonia and spermatocytes were intensely aniline blue positive and the nuclei of young spermatids moderately positive, while the nuclei of late elongated spermatids and spermatozoa were aniline blue negative. The nuclei of spermatogonia and young spermatids were basicallyy NQS negative and there were a few granules of weak NQS positive in the nuclei of primary spermatocytes, while the nuclei of late elongated spermatids and spermatozoa were NQS positive. Under the electron microscope, the PTA positive chromatin in the nuclei of early spermatids with round nucleus (steps 1 to 8)was fibrillar or granular in appearance. Along with the condensation of nuclei of spermatids(steps 9 to 13), the nuclear stain ability increased. The positive chromatin in the nuclei of spermatids (steps 14, 15) was disappeared progressively, in the direction from cranial to caudal along with the further condensation of nuclei. The nuclei of late spermatids with elongated nucleus (steps 18, 19) and spermatozoa were PTA negative. These observations suggest that the nucleoprotein transition from histones to protamine (S_1) occur during spermiogenesis and that this process could be divided into two consecutive steps, i. e. from histones through an intermediate phase of transition proteins to protamine.
