摘要
应用酶学和组织显微技术,研究了镉(Cd)对背角无齿蚌(Anodonta woodiana)外套膜组织中细胞凋亡相关酶Caspase-3,8,9活性、H2O2含量和组织细胞超微结构的影响。结果显示,与对照组相比,随着Cd质量浓度的增加,外套膜Caspase-3活性表现为先降低后显著升高的趋势(P<0.05);Caspase-8活性呈现逐渐升高,差异显著(P<0.05);Caspase-9活性在低质量浓度和高质量浓度组显著降低,但中高质量浓度组显著升高(P<0.05)。随着Cd质量浓度的增加,外套膜中H2O2含量呈现逐渐增高的趋势,差异显著(P<0.05)。当Cd质量浓度为16.86 mg/L时,外套膜组织细胞结构的变化明显;细胞核染色质不规则凝聚、固缩和边集,核膜破裂;线粒体肿胀、嵴数量减少、空泡化比较严重;微绒毛排列杂乱、大部分断裂并且空泡化严重。当Cd质量浓度为67.45 mg/L时,外套膜组织细胞损伤更加明显;染色质大部分凝聚、固缩和边集,核膜严重肿胀并破裂;粗面内质网板层状结构解体后形成许多大小不同的小泡。研究表明,外套膜在酶活性和组织细胞结构上对镉的反应较快且更具规律性,而且具有明显的剂量效应关系。
This study examines the effects of cadmium（Cd）on the activities of apoptosis-related enzymes, the level of H2O2 and ultrastructure of the mantle of the freshwater mussel Anodonta woodiana. The freshwater mussels were exposed to different concentrations of Cd（8.43, 16.86, 33.72, 67.45 mg/L）for 96 h. Activities of Caspase-3, 8, 9, as well as H2O2 level were measured by enzymatic assays.The result showed that with the increase of Cd concentration, Caspase-3 activity decreased initially and increased subsequently（P〈0.05）. The change in Caspase-9 activity followed the similar pattern. The activity of Caspase-8 increased significantly after the mussels exposed to Cd in a dose-dependent manner（P〈0.05）. With the increase of Cd concentration, H2O2 level increased gradually in a dose-dependent manner（P〈0.05）. Moreover, after Cd treatment（16.86, 67.45 mg/L）for 96 h, histological abnormalities were observed by electronic microscopy in the mantle cells. After Cd treatment（16.86 mg/L）, the obvious changes of cellularity were shown by the following features： chromatin condensed near nuclear membrane, nuclear membrane swelled and ruptured; mitochondria became swelling and vacuolating gradually, and some mitochondrial crisae disintegrated; microvilli arranged disorderly, broke off and were decreased gradually, the vacuole appeared. After Cd treatment（67.45 mg/L）, the histological abnormalities were more apparent by the following features： most of chromatin condensed near nuclear membrane, nuclear membrane swelled and ruptured seriously; mitochondria became swelling and vacuolating, and most of mitochondrial crisae disintegrated; rough endoplasmic reticulum disintegrated, and formed many different sizes of vesicles. In conclusion, Cd can cause significant changes in the enzymatic activities and histological abnormalities to the mantle of the animal.
出处
《山西农业科学》
2016年第8期1108-1113,共6页
Journal of Shanxi Agricultural Sciences
基金
山西省普通高校生物学特色重点学科建设项目(2011-SXDX-SWX-003)
