氨氮污染对菲律宾蛤仔鳃组织的靶向毒性效应研究

According to “Reports on the State of the Environment in China” in the recent years, ammonia nitrogen has been one of the major factors contributed to the coastal pollution. Consequently, ammonia nitrogen pollution is an important environmental stressor for the healthy development of shellfish aquaculture around China’s coastal regions. Now many of the toxicological studies of ammonia nitrogen on mollusks focused on limited issues of traditional toxicology, and few studies reported the corresponding mechanisms. In the light of toxic pathways of other aquatilia, gill is one of the primary target tissues of ammonia nitrogen. But few mollusk researchers targeted gill tissue and discussed the adverse effects of ammonia nitrogen on its structure and function. Our former studies of ammonia nitrogen on Ruditapes philippinarum suggested disturbance in muscle protein metabolism and neural signal transmission. It was first discovered in mollusks. Taking advantage of transcriptomics and traditional toxicology, this project aims the gill of R. philippinarum as target tissue to thoroughly explain toxicology of ammonia nitrogen on mollusks. It would lay foundation to bio-indication and ecological risk assessment of ammonia nitrogen pollution.

近几年的海洋公报显示氨氮一直都是近海海域最突出的污染因子，氨氮污染成为制约我国海洋贝类养殖业健康发展的重要环境因素之一。目前贝类的氨氮毒理研究局限于描述几种传统毒理学反应，深层毒理机制研究较少。根据氨氮对水生动物的致毒途径可以看出，鳃是氨氮损害的主要靶组织，但是以贝类鳃组织作为研究对象，深入探索其毒性效应的研究很少。我们前期代谢组学结果表明，氨氮污染很可能通过干扰鳃组织的肌肉蛋白质代谢和神经信号传递而影响鳃的结构与功能，这在贝类的氨氮毒理学研究中尚属首次发现。本项目将以贝类的鳃组织作为研究对象，以已经获得的代谢组学结果为基础，利用转录组学和传统毒理学技术，深入阐释氨氮污染对菲律宾蛤仔鳃组织的靶向毒性效应，同时为氨氮污染的生物监测和生态风险评估奠定基础。

随着现代社会的飞速发展，人类活动给近岸海域带来很多环境污染物，造成近岸海水养殖生态环境的恶化，氨态氮是我国近年来一直居高不下的环境污染物，成为制约我国贝类养殖业健康发展的主要污染因子之一。目前氨氮对贝类的生态毒理研究，主要集中于传统毒理学方面，对其毒理学效应评价不够全面，同时对其致毒机制也不甚了解。本研究从传统毒理学、代谢组学和转录组学方面，选择菲律宾蛤仔的鳃组织作为研究对象，采用环境相关浓度的氨态氮对其进行急性（1天）和亚急性（30天）氨氮暴露，结果发现：氨态氮对贝类具有严重的毒性作用，通过显著影响干扰其氧化还原平衡、干扰膜系统的稳定性、扰乱神经递质的表达与代谢、削弱其免疫系统并干扰重要生命物质（氨基酸、脂类、碳水化合物等）的代谢，从而显著影响其鳃组织的结构与功能，导致鳃丝组织摄食和呼吸功能发生显著变化，严重影响菲律宾蛤仔的正常生命活动，从而对贝类养殖业造成不可低估的负面影响。本项目的顺利实施，为氨氮污染对贝类养殖业的生物监测和生态风险评估奠定了牢固的基础。