急性和亚慢性镉处理对溪蟹鳃组织影响的比较  

Comparison study on gills of freshwater crab Sinopotamon henanense exposed to acute and subchronic cadmium

作　　者：轩瑞晶[1] 吴昊[1] 李颖君[1] 井维鑫[1] 王兰[1] 

机构地区：[1]山西大学生命科学学院,山西太原030006

出　　处：《广东农业科学》2013年第7期123-126,共4页Guangdong Agricultural Sciences

基　　金：山西省研究生优秀创新项目(20123002)

摘　　要：为了比较研究急性和亚慢性镉处理对河南华溪蟹(Sinopotamon henanense)鳃组织病理学和生物化学的影响,设置了急性(4 d,28.55 mg/L Cd2+)和亚慢性(21 d,2.86 mg/L Cd2+)镉处理组及对照组。将处理组和对照组的部分鳃组织采用光学显微技术进行组织病理学的观察,对剩余鳃组织分别采用比色法、火焰原子吸收法和镉-血红蛋白饱和法检测了总超氧化物歧化酶(SOD)活性、膜脂质过氧化产物丙二醛(MDA)含量、Cd2+蓄积和金属硫蛋白(MT)含量,并计算了MT的镉结合率(CBP)。结果显示,急性镉处理后鳃叶肥大增厚,部分上皮细胞中出现空泡;亚慢性处理后,鳃叶边缘通道紧缩,上皮细胞高度肿胀,鳃血腔缩小变窄。所检测指标在处理组中显著高于对照组,其中Cd2+蓄积量和SOD活性在两个处理组之间没有显著差异,急性处理组MT含量显著高于亚慢性组,而亚慢性组MDA含量显著高于急性组。表明亚慢性镉处理对河南华溪蟹鳃组织结构的损伤程度比急性组严重,可能与亚慢性组鳃的MT含量低,脂质过氧化程度高有关。To compare and explore histopathological and biochemical alterations in gills of the freshwater crab Sinopotamon henanense caused by acute and subehronic cadmium exposure, the crabs were acutely exposed to 28.55 mg/L Cd^2＋ for 4 d and subchronieally exposed to 2.86 mg/L Cd^2＋ for 21 d. At the end of the exposures, gills from control and experimental crabs were partially fixed and prepared for histology examination, and the others were used for the measurement of total superoxide dismutase （SOD） activity, malondialdehyde （MDA）coneentration, Cd^2＋ accumulation and metallothionein （MT） levels with the methods of speetrophotometry, flame atomic absorption speetrophotometry and Cd/Hemoglobin saturation, respectively. The Cd-binding potential （CBP） of MT in the gills was calculated. Branchial histological examinations showed that acute cadmium exposure caused branchial laminae hypertrophic and hemolymph vessels were relaxed. After the subchronic exposure, marginal channels of the laminae were shrunken. Non-tissue spaces separated epithelial cells from wavy cuticle. Hemolymph vessels were narrowed even disappeared due to the extrusion of seriously vaeuolized and swollen epithelial cells. There were no significant differences in Cd^2＋ accumulation, CBP and total SOD activity between acute and subchronic cadmium exposures. However, MT level in acute-exposed group was significantly increased compared with that in subehronie-exposed group, and MDA concentration was exactly the opposite. It is concluded that gill damage caused by subehronic cadmium exposure was more serious than that caused by acute exposure, and lower MT content and higher lipid peroxidation level may play an important role in its damage.

关 键 词：河南华溪蟹 鳃 显微结构 应激反应 镉 

分 类 号：Q175[生物学—水生生物学]