急性镉染毒对河南华溪蟹精子质量的影响

采用急性毒性实验方法,研究了镉(Cd2+)对河南华溪蟹(Sinopatamon henanense)精子质量的影响.实验设置了5个Cd2+浓度组(7.25、14.5、29、58和116 mg·L-1)和1个空白对照组,在2个染毒时间(5d和7d)采用特异性的荧光染料和流式细胞术(FCM)对精子成活率、膜完整性、顶体完整性及染色质结构进行了测定.结果显示,随着Cd2+浓度的增加和染毒时间的延长,精子的成活率下降,质膜和顶体缺失率上升,异染色质所占比率上升.在Cd2+浓度为58、116 mg·L-1条件下暴露5d后,精子成活率显著降低(p ＜0.05)；Cd2+浓度为116 mg·L-1时,精子质膜完整性和染色质结构均有明显的损伤；而顶体状态在Cd2+浓度为29 mg·L-1时就呈现显著的损伤(p＜0.01).在Cd2+浓度为29、58、116mg·L-1条件下染毒7d后,精子成活率、质膜完整性和顶体完整性降低；在所有的染毒组,DNA结构受到了显著的破坏.结果表明,Cd2+暴露对华溪蟹精子质量有明显的影响.

Effects of acute cadmium on sperm quality of Sinopotamon henanense

To explore the effects of acute cadmium (Cd²⁺) on the sperm quality of Sinopotamon henanense, the freshwater crabs Sinopotamon henanense were exposed to 0, 7.25, 14.5, 29, 58, and 116 mg·L^-1 Cd²⁺ for 5 and 7 d. Using specific fluorescent dyes and flow cytometry (FCM), the sperm quality was investigated including sperm viability, plasma- and acrosomal-membrane integrity and chromatin integrity. Our results showed that with the increase of Cd²⁺ concentration and exposure timethe sperm viability decreased, plasma- and acrosomal-membrane loss increased and the ratio of abnormal DNA increased. When exposed to 58 and 116 mg·L^-1 Cd²⁺ for 5 d, the sperm viability was significantly reduced; sperm membrane integrity and chromatin structure were also significantly damaged by 116 mg·L^-1 Cd²⁺; the acrosomal integrity were also damaged starting at 29 mg·L^-1 Cd²⁺. When exposed to 29, 58, and 116 mg·L^-1 Cd²⁺ for 7 d, the sperm viability was significantly lowered and plasma- and acrosomal-membrane integrity were undermined. The chromatin structure, however, were damaged at all Cd²⁺-exposed groups. Our results indicated that Cd²⁺ exposure can damage sperm quality severely of the crab species.