重金属复合污染场地对花背蟾蜍雄性性腺的毒性作用

以花背蟾蜍为研究对象,以包头市某尾矿库南侧受污染的水域湿地和相对无污染的小白河黄河湿地保护区为研究样地。对比分析雄性花背蟾蜍形态学指标、精巢脏器系数、精子动态参数、精子畸形率、性激素、红细胞微核率和DNA损伤等相关指标,研究重金属复合污染场地对花背蟾蜍雄性性腺的毒性效应。结果显示:与小白河湿地相比,尾矿库湿地花背蟾蜍条件因子和精巢脏器系数显著高于小白河湿地(P<0.01)。尾矿库花背蟾蜍精子的鞭打频率显著升高,而精子活力显著降低(P<0.05),精子畸形率、红细胞微核率和DNA损伤均显著高于小白河湿地(P<0.05)。结果表明:尾矿库复合污染通过降低精子质量,增加红细胞微核率和DNA损伤对花背蟾蜍的雄性性腺造成毒理学影响,花背蟾蜍通过升高条件因子和精巢脏器系数来缓解复合污染的毒性胁迫。该成果对重金属复合污染场地两栖类动物种群保护以及生态平衡维护有着积极作用。

TOXIC EFFECTS OF HEAVY METALS CONTAMINATED SITE ON MALE GONAD OF BUFO RADDEI

In this study, Bufo Raddei was taken as the research object, and the polluted water wetland and the relatively pollution-free Yellow River Wetland Reserve on the south side of the tailing wetland in Baotou, were taken as the research sites. Through analysis of morphological indexes, testis organ coefficient, sperm dynamic parameters, sperm deformity rate, sex hormone, micro-nucleus rate, and DNA damage of different male B. raddei, the toxic effect of compound pollution of tailing wetland on male gonads of B. raddei was studied. The results showed that the condition factor (CF) and the testis organ coefficient of B. raddei in tailing wetland was significantly higher than that in Xiaobaihe wetland (P < 0.01). In addition, the whipping frequency of sperms in the tailing wetland was significantly improved, while the sperm motility was significantly decreased (P<0.05). The sperm deformity rate, erythrocyte micro-nucleus, and DNA damage were obviously higher than that in the Xiaobaihe wetland (P<0.05). The results showed that the compound pollution of tailing wetland resulted in decrease of the sperm quality and increase of the micro-nucleus rate and DNA damage, which influenced the toxicological effect of male gonads. The toxic stress of compound pollution was eased by increasing the condition factor and the coefficient of spermatozoa. The above results had positive effect on the population protection, and ecological balance maintenance of amphibians in the compound pollution site of heavy metals.