乙烯菌核利对稀有鮈鲫性腺组织及相关基因转录水平的影响

Vinclozolin Affected the Gonad of Rare Minnow( Gobiocypris rarus) at Histopathological and Transcriptional Levels

乙烯菌核利在哺乳动物实验中被广泛证实具有抗雄激素效应,而对鱼类的研究结论目前并不统一。将性成熟稀有鮈鲫分别暴露于0、2、10、50μg·L-1乙烯菌核利21 d,研究环境浓度下乙烯菌核利对鱼类生殖系统的影响及作用机制。结果表明,雌鱼的性腺指数(GSI)、肝脏指数(HSI)在所有浓度组均显著降低(p<0.05),同时卵巢组织中卵泡的发育受到了抑制;而雄鱼仅HSI在最高浓度组(50μg·L-1)出现显著降低(p<0.05),精巢组织切片也未观察到明显损伤,说明乙烯菌核利对雌鱼生殖系统的影响大于雄鱼。在转录水平上,雌鱼性腺中er mRNA、vtg mRNA分别在50μg·L-1和10、50μg·L-1时显著升高(p<0.05),ar mRNA在所有浓度组显著升高(p<0.05);而雄鱼性腺中ar mRNA、dmrt1 mRNA水平分别在10μg·L-1浓度组和所有浓度组显著降低(p<0.05),er mRNA在所有浓度组显著降低(p<0.05),说明雌雄鱼对乙烯菌核利暴露的分子响应机制存在差异。综上,环境浓度下乙烯菌核利短期暴露会对稀有鮈鲫生殖系统产生一定的影响,并且雌雄鱼在敏感性和分子响应机制上都存在差异。

Vinclozolin has been proved as a mammalian anti-androgen. However, data concerning its effects infish is limited. In the present study, senually matured rare minnow were exposed to environmentally relevantconcentrations of vinclozolin （0, 2, 10, 50μg·L-1） for 21 days. In the females, the hepatosomatic index （HSI）and gonadsomatic index （GSI） were significantly decreased at all treatments （p 〈0.05）, and the development ofovarian follicles were inhibited; while in the males, no obvious changes were observed except for a decreaseof HSI at 50μg·L-1（p 〈0.05）. Real-time PCR revealed significant increases of the gonadal transcripts of er （50μg·L-1）, vtg （10, 50 μg·L-1）, and ar （all concentrations） in the females （p 〈0.05）, but decreases of those of ar（10 μg·L-1）, dmrtl （all concentrations） and er （all concentrations） in the males （p 〈0.05）. Above all, short term exposure to vinclozolin at environmentally relevant concentrations could cause adverse effects on the gonad of rare minnow. The results also indicated differences in the sensitivity and responsive mechanism upon vin- clozolin exposure, which should be considered in further studies on other endocrine disrupting chemicals.