[关键词]
[摘要]
采用生态学单因子梯度试验,研究在不同铜(Cu2 )浓度梯度的水环境中中华绒螯蟹体内Cu2 分布的变化及其与生长相关的消化酶活性的影响.在未添加Cu2 的对照组中,中华绒螯蟹中Cu2 含量以鳃为最高,表皮次之,肝胰腺最低.随着水环境中Cu2 浓度的增高,相应组织中的Cu2 含量呈现不同的变化趋势,肝胰腺增加最快,鳃次之,表皮则最慢.显示在高Cu2 水环境下,肝胰腺是Cu2 主要的累积场所.不同浓度的Cu2 对肝胰腺类胰蛋白酶、胃蛋白酶、淀粉酶和纤维素酶活性均有不同程度的抑制,且Cu2 浓度越高,抑制作用越明显.对脂肪酶活性则有浓度依存的增强作用.表明随着水环境中添加的Cu2 浓度的增加,肝胰腺将是最主要的Cu2 积累和代谢器官,其代谢酶活性的变化可以灵敏地反映Cu2 的胁迫程度和毒性.
[Key word]
[Abstract]
Effects of different water-borne copper( Cu^2+ ) ( 0.00, 0.01, 0.10, 1.00, 5.00 mg? L^-1 ) on distribution of copper in the body of Eriocheir sinensis and activities of some main digestive enzymes were studied by Single Gradient Factor Experiments. Among gill, epidermis and hepatopancreas of the animals in the control group without additive Cu^2+ , average Cu^2+ was 0.074, 0.036, 0.023 mg?g^-1 wet weight, respectively, which were determined by ICP-AES. When increasing of water-borne Cu^2+ except for the hepatopancreas and epidermis in tested group with 0.01 mg?L^-1 water-borne Cu^2+, Cu^2+ level increased significantly (analyzed by SPSS software) in all organs studied and especially in the hepatopancreas. In the tested group in which water-borne Cu^2+ was 5.00 mg?L^-1 Cu^2+ level among the gill, epidermis, and hepatopancreas was 0.307, 0. 191, 0.341 mg?g^-1 wet weight, respectively. Furthermore, in the hepatopancreas the inhibition effect could be noted on activities of some important digestive enzymes, such as the typase, pepsin, amylase and cellulase in different extents during increase of water-borne Cu^2+ . It is notable that such effect on the amylase was the most obvious even the level of additive Cu^2+ was only 0.01mg?L^-1 that is the level of the National Water Purity Standard for Fisheries. Comparing with the control group, the activity of the amylase dropped sharply from 305.01 ? 32.23 to 36.81 ? 4.84 U?mg^-1. The maximum inhibition rate of this enzyme could be recorded as high as 89.96% in the tested group with 5.00 mg?L^-1 of water-borne Cu^2+ . In contrast, the activity of the lipase enzyme was found increasing in all tested groups between 346.15% to 646.15%. The present study suggests that the different functional characteristics of the gill, epidermis and hepatopancreas may contribute to the change of Cu^2+ distribution pattern among these organs for Eriocheir sinensis when the additive Cu^2+ level in water was increased. Meanwhile, the hepatopancreas seems to be the main bioac Cu^2+ mulation site, as well as the metabolic organ for Cu^2 + . Moreover, the variations on the activity of the typase, pepsin, amylase and cellulase enzymes can sensitively indicate the inhibition effect of Cu^2+ as well as its toxicity.
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[基金项目]
中国水产科学院人才基金