Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture, College of Fisheries, Huazhong Agriculture University, Wuhan 430070, China.
Beijing Key Laboratory of Industrial Wastewater Treatment and Reuse, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing 100085, China.
Aquat Toxicol. 2020 Jan;218:105333. doi: 10.1016/j.aquatox.2019.105333. Epub 2019 Nov 10.
In the current study, to investigate the effect of imidacloprid on benthic bivalves, adult Asian clams (Corbicula fluminea) were exposed to 0, 20, 200, and 2000 μg/L imidacloprid for 30 d. Imidacloprid significantly inhibited the siphoning and burrowing behaviour (p < 0.05) of the clams. Significant histopathological changes were associated with degeneration of the cilium, the contraction and adhesion of the lymphocyte, and the swelling of epithelium cells in gills, and there was notable degeneration in the digestive tubules, haemolytic infiltration in the connective tissue and epithelial cell necrosis in the digestive glands in the 2000 μg/L treatment group. The activity of AChE in the digestive glands was significantly inhibited at all treatment levels, whereas this inhibition was observed in gills only in the 2000 μg/L treatment (p < 0.05). Additionally, indicators of the antioxidant system (e.g., SOD, CAT, and GST activity) and MDA content were significantly increased in the gills and digestive glands with all treatments (p < 0.05). Moreover, the mRNA expression levels of Hsp genes (hsp 22, hsp 40, hsp 60, hsp 70, hsp 90) and multixenobiotic resistance (MXR) system-related genes (abcb1, abcc1) were significantly downregulated (p < 0.05). Therefore, our results suggest that imidacloprid changes the oxidative stress, cellular detoxification, and MXR system of C. fluminea. Our findings provide new insights into the effects of neonicotinoids on benthic bivalves such as C. fluminea.
在本研究中，为了研究吡虫啉对底栖双壳贝类的影响，将成年亚洲河蚌（Corbicula fluminea）暴露于 0、20、200 和 2000μg/L 的吡虫啉中 30 天。吡虫啉显著抑制了河蚌的虹吸和挖掘行为（p<0.05）。显著的组织病理学变化与纤毛退化、淋巴细胞收缩和粘连以及鳃上皮细胞肿胀有关，在 2000μg/L 处理组中还观察到消化管明显退化、结缔组织溶血浸润和消化腺上皮细胞坏死。在所有处理组中，消化腺中的 AChE 活性均显著受到抑制，而在 2000μg/L 处理组中仅在鳃中观察到这种抑制（p<0.05）。此外，抗氧化系统的指标（如 SOD、CAT 和 GST 活性）和 MDA 含量在所有处理组的鳃和消化腺中均显著增加（p<0.05）。此外，热休克蛋白基因（hsp 22、hsp 40、hsp 60、hsp 70、hsp 90）和多药耐药（MXR）系统相关基因（abcb1、abcc1）的 mRNA 表达水平也显著下调（p<0.05）。因此，我们的结果表明，吡虫啉改变了 C. fluminea 的氧化应激、细胞解毒和 MXR 系统。我们的研究结果为新烟碱类杀虫剂对底栖双壳贝类（如 C. fluminea）的影响提供了新的见解。
