Zn^(2+)对中华绒螯蟹溞状幼体肝胰腺超微结构的影响  

ULTRASTRUCTURAL STUDY OF THE TOXIC EFFECT OF DIFFERENT CONTENT OF Zn^(2+) ON HEPATOPANCREAS IN THE LARVAE OF CHINESE CRAB, Eriocheir sinensis

作　　者：成永旭[1] 徐兆礼[2] 陈亚瞿[2] 

机构地区：[1]上海水产大学农业部水产增养殖生态和生理重点实验室,上海200090 [2]中国水产科学院东海水产研究所,上海200090

出　　处：《Zoological Research》2000年第5期343-347,共5页动物学研究（英文）

基　　金：国家自然科学基金!(3990 0 112 );交通部长江口深水航道建设有限公司资助

摘　　要：研究了不同Zn2 +浓度对中华绒螯蟹 (Eriocheirsinensis)状幼体肝胰腺细胞超微结构的影响。当Zn2 +浓度超过 2 0 0 μg/L时 ,与对照组相比 ,肝胰腺结构受到了显著的影响。成熟和正在形成的B细胞的空泡中有很多含有金属的电子致密颗粒 (EDG ,可能为金属蛋白复合体 ) ,随着B细胞的成熟和B细胞从肝胰腺管壁上脱落 ,这些EDG也被释放到管腔中 ,因此肝胰腺的管腔中常有许多此类颗粒存在。B细胞空泡或管腔中的EDG与环境中Zn2 +浓度高低呈正相关。E细胞质中也出现了很多空泡 ,与正常E细胞的结构明显不同。R细胞的细胞质常解体形成大的空泡 ,被破坏的程度较为严重。在Zn2 +浓度 >10 0 0 μg/L时 ,肝胰腺遭到严重破坏 ,细胞结构几乎不存在。研究结果表明 ,肝胰腺的B细胞在Zn2 +的解毒方面起重要作用 ,但当Zn2 +浓度超过了肝胰腺B细胞的解毒能力时 ,就会引起肝胰腺细胞 (如R和E细胞 )结构异常 ,甚至破坏整个肝胰腺细胞结构 ,从而影响幼体的生长 ,甚至造成死亡。The impact of different concentrations of Zn 2+ on the ultrastucture of hepatopancreas in larval (zoea Ⅳ) of Chinese crab, Eriocheir sinensis was studied after being exposed for 96?h by using transmission electronic microscope.The result demonstrated that significant ultrastructural changes,which occurred in hepatopancreas cells,were found after exposed above 200?μg/L Zn 2+ . When compared with control group (31 8?μg/L Zn 2+ ).B cells have numerous vacuoles or a large vacuole with a number of insoluble Zn electronic dense granules (EDG) in membrane lined types. When the mature B cells are extruded from the epithelium of the hepatopancreas tubules,these EDGs in vacuole will be released as the vacuoles which have burst. The EDGs will be found in the lumen. The production of EDGs in the lumen and the vacuole of B cell have been correlated directly with the ambient concentration of Zn 2+ .The EDGs in lumen then may be removed via the gut and excreted directly to outside and they are insoluble. The cytoplasm of R cells are often disoganized,vacuolized and form large vacuoles.The R cell are seriously damaged.The cytoplasm of E cell have large amount of vacuoles,which may be resulted from the degeneration of swollen mitochondrion.This shows that the E cells have lost their ability to differentiate to other cells. When the concentration of Zn 2+ is high (1031 8?μg/L Zn 2+ ),the structure of hepatopancreas will be seriously destroyed and no cell structure can be found. This observation suggested that formation of EDG in B cells was an important cellular detoxifying mechanism,in which Zn 2+ or other heavy metal were incorporated into intracellular insoluble form (may be metal protein complexes).These are harmless to the tissue and cell.Pathological effects occur in tissues when the rate of influx of a toxicant,such as Zn 2+ ,exceeds rate of detoxification and excretion.In this experiment,the effect was found to be the damage of R and E cell,even the all cells in hepatopancrea

关 键 词：中华绒螯蟹 Zhao状幼体 超微结构 肝胰腺 锌污染 

分 类 号：Q954[生物学—动物学]