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Both pentachlorophenol and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) had been studied widely because of their probable anti-estrogenic activity. Sodium pentachlorophenol (PCP-Na), as a industrial product used in many fields, usually contains a trace of TCDD. The aim of this study was to assess the anti-estrogenic effect of PCP-Na in juvenile goldfish (Gurassius auratus) hepatocyte cultures using vitellogenin (VTG) as the biomarker. The ID50 of PCP-Na was investigated and then a series of concentrations (0.001 0.5 μg/ml) of PCP-Na were evaluated to estimate the anti-estrogenic activity. Results showed that PCP-Na was cytotoxic for hepatocytes even at very low concentration 〈1.21 μg/ml, and it could not induce VTG at any concentrations tested. Since it failed to stimulate VTG production, the possibility of its anti-estrogenic effect was tested, and a well-known anti-estrogenic compound-tamoxifen was used as positive control. PCP-Na caused a reduction in VTG synthesis in juvenile goldfish (Carassius auratus) hepatocytes at concentrations 〉0.1μg/ml when co-exposure with 1μg/ml 17β-estradiol (E2), making its anti-estrogenic activity approximately as potent as tamoxifen. Our results indicate that PCP-Na can act as negative modulators of estrogenic function in juvenile goldfish (Carassius auratus) hepatocytes. 相似文献
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用酶联免疫吸附法(ELISA)对E2诱导的鲫鱼幼鱼血清中卵黄蛋白原(VTG)进行了测定,并用原子吸收分光光度法测定了血清中的钙含量.结果表明:鲫鱼幼鱼血清中VTG和钙含量与E2的暴露剂量均有很好的剂量-效应关系.对血清中VTG和钙含量进行回归分析,发现二者具有较好的相关性,R2=0.928 7.因此,用原子吸收法测定血清中的钙含量从一定程度上可以替代ELISA法间接确定血清中的VTG含量,并对化学物质的雌激素效应进行了评价. 相似文献
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为研究3种典型有机氯农药(%-六六六、p,p'-DDT和七氯)低浓度暴露对锦鲤幼鱼的雌激素效应及其体内富集效应,将锦鲤幼鱼暴露于有机氯农药的6个浓度组中进行20 d慢性毒性试验,测量血清中游离钙和蛋白结合磷含量及体内各组织有机氯农药残留。结果表明,在低浓度暴露20 d后,锦鲤幼鱼血清中游离钙和蛋白结合磷含量均随暴露浓度增加而呈先增后减之势,产生了明显的雌激素效应。p,p'-DDT在鱼体各组织中的富集能力远高于%-六六六和七氯;p,p'-DDT主要在鱼油中富集,其次为鱼肝、鱼鳃和鱼皮;%-六六六和七氯主要在鱼肝中富集,其次为鱼皮、鱼鳃和鱼油;3种有机氯农药在鱼肉中的富集相对较少。 相似文献
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Summary. Juvenile hormones are sesquiterpenoids that regulate developmental processses such as metamorphosis and reproduction in insects.
Insect juvenile hormone III (JH III), methyl-10R,11-epoxy-3,7,11-trimethyl-2E,6E-dodecadienoate, has also been identified in two sedge species, Cyperus iria and C. aromaticus (Toong et al. 1988). Potential allelopathic activity of this compound and the structurally related sesquiterpenoid farnesol was investigated
using seed germination and seedling growth assays with radish, lettuce and rice. Treatment of seeds with JH III delayed lettuce
seed germination and potently inhibited rice shoot growth. Both farnesol and JH III inhibited the growth of C. iria seedlings. The antimicrobial activity of JH III was also tested on a taxonomic and ecologically diverse range of fungi. Using
the classic cytotoxic disk assay, JH III did not effect growth of the fungal species tested. We believe that JH III may contribute
to the aggressive nature of this invasive weed species.
Received 11 October 1999; accepted 26 February 2000 相似文献
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克氏原螯虾亚成体和幼体对不同氨浓度水环境的选择 总被引:1,自引:0,他引:1
以NH4Cl为主要成分配比成不同浓度的氨溶液,以Y型水迷宫为水环境的选择实验装置,从克氏原螯虾的行为学角度出发,探究其对不同浓度氨溶液的趋避选择性。实验共设置5个浓度梯度:4750、7125、9500、14250和19000 mg/L,其pH值为70,水温为20±05℃。以体长为501±043 cm的克氏原螯虾亚成体及体长为075±015 cm的幼体为实验对象,在Y型水迷宫中的两个选择区中分别放入污水和清水,供实验虾进行选择,记录选择清水和污水的次数及未作出选择的次数,对数据进行非参数检验的二项分布检验。结果表明亚成体在氨浓度4750、7125、9500及14250 mg/L时,没有明显选择性,在氨浓度19000 mg/L时,显著避开污水;幼虾在氨浓度4750 mg/L时,没有明显选择性,在氨浓度7125和9500 mg/L时,显著避开污水,当氨浓度达到14250 mg/L及以上时,出现中毒症状,丧失选择能力。该结果证明克氏原螯虾对高浓度的氨氮型污水不仅没有偏好,而且当浓度达到一定数值时会主动躲避,或躲避不及发生行为异常乃至死亡 相似文献
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S. V. Titov 《Russian Journal of Ecology》2003,34(4):255-260
Natural dispersal of young animals was studied in the colonies of Spermophilus major and S. suslicus ground squirrels in the Volga region. On the basis of data obtained, this process was modeled taking into account the spatial–ethological structure of the colonies. In both species, male dispersal was more active, whereas the degree of natal philopatry was higher in females. The results of the study do not confirm the aggression concept of juvenile dispersal and indicate that its causes are related to hereditary behavioral tendencies. These results are compared with data on juvenile dispersal in other species of the genus Spermophilus. 相似文献
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海湾扇贝苗运输环境条件的研究 总被引:5,自引:0,他引:5
在实验室条件下,研究了温度和湿度对海湾扇贝苗存活的影响;双结合生产性运输,研究了温度,溶解氧,运输季节和贝苗规格对运输贝苗存活的影响。担子同运输包装贝苗方法:12h以内的运输,用干贮法;12-18h以内,用淋贮法,18-21h以内,用水贮帆布桶法。21-34h内,用水贮保温箱法。运输贝苗的主要条件是;低温,高湿度或足够的溶解适宜季节,适宜贝苗规格。 相似文献