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1.
Although fish feed supplemented with Chinese parsley (CP), Coriandrum sativum, does not affect the health of rainbow trout Oncorhynchus mykiss, it has the remarkable effect of reducing the uptake of Cd (12–17% compared with controls without CP). Here, we measured
the change in the amount of metallothionein (MT) in the liver and kidney using gel permeation chromatography-high-performance
liquid chromatography (TSK GEL SW 3000 column). The increase in MT content over time in the Cd-fed groups corresponded to
the change in Cd accumulation. Gel permeation was performed with soluble fractions from the fish liver and kidney, and changes
in the Cd, Cu, and Zn concentrations over time for each fraction, and the relationship between the form of Cd that accumulated
in tissues and its toxicity were measured. A nontoxic MT fraction of 7,000 Da and a high-molecular-weight fraction of approximately
60,000 Da were isolated from the soluble fractions. The induction of nontoxic MT–Cd was higher in the CP-supplemented groups
than in the control groups. The synergetic actions of several compounds in CP may contribute to bind MT, thereby preventing
accumulation of harmful heavy metals and essential metals in fish. 相似文献
2.
Huifeng Ren Huijuan Jia Seunghwan Kim Masashi Maita Shuichi Sato Minato Yasui Hideaki Endo Tetsuhito Hayashi 《Fisheries Science》2006,72(2):263-269
ABSTRACT: Toxic heavy metals such as cadmium (Cd) accumulate in cultured fish from solid-form feed mixtures. In this paper, two natural ingredients, supposed to inhibit accumulation of heavy metals in the fish body, were investigated to develop a functional feed mixture for healthy fish. Three test diets: (i) ♯1, regular diet as negative control; (ii) ♯2, ♯1 + 2% lyophilized Chinese parsley Coriandrum sativum (CP); and (iii) ♯3, ♯1 + 3% chitosan (CT), were each fed to 50 rainbow trout Oncorhynchus mykiss once a day, at the constant rate of 1.0–1.2% of body weight for 12 weeks. No undesirable effect on fish growth was observed by an addition of either CP or CT to regular feed. Then, 10 mg Cd was added to 1 kg each of the three test diets and they were named as: (i) ♯4, ♯1 + Cd; (ii) ♯5, ♯2 + Cd; and (iii) ♯6, ♯3 + Cd, respectively. The fish given positive a control feed (diet ♯4) for 3 weeks accumulated Cd in the liver and kidney at approximately 0.52 mg/kg. However, Cd in ordinary muscle was found to be just above the detection limit. Upon accumulation of Cd, three groups of 50 fish were each fed test diets ♯4, ♯5, and ♯6 for 12 weeks at the same feed rate described above. The concentrations of Cd accumulated in the liver, kidney, and ordinary muscle of the fish were measured every 3 weeks. Contrary to the positive control fish fed diet ♯4, those fish fed test diets ♯5 and ♯6 accumulated 20–30% and 25–40% less Cd in the liver, respectively. Test diets were a little less effective for inhibition of Cd uptake in the kidney than that observed in the liver. These results suggest that addition of CP or CT to fish feed might be used to decrease toxic heavy metal accumulation in fish. 相似文献
3.
K. Hylland C. Haux C. Hogstrand K. Sletten R. A. Andersen 《Fish physiology and biochemistry》1994,13(1):81-91
One isoform of the low-molecular-weight metal-binding protein metallothionein (MT) has been isolated from the liver of Atlantic
cod by size-exclusion and ion-exchange chromatography. Cod MT contained 33% cysteine, no aromatic amino acids or arginine.
As is the case for other piscine MTs, the N-terminus of cod MT lacked the asparagine in position 4 which is present in mammalian
MTs. In addition, cod MT differed from all other vertebrate MTs described in that the N-terminal methionine was not acetylated.
Antibodies were raised in rabbits against hepatic MT from cod by repeated injections of native protein mixed with adjuvant.
Anti-cod MT antisera cross reacted with similarly-sized proteins in liver, brain, anterior kidney, posterior kidney, spleen,
intestine, gills and ovaries. The putative MT in cod brain migrated differently to that of the other tissues in native gel
electrophoresis. Intraperitoneally injected Cd (1 mg/kg) was nearly entirely associated with the MT-peak in hepatic and renal
cytosols, whereas a single injection of Zn (10 mg/kg) resulted in increases in all cytosolic Zn pools of the liver and no
apparent change in cytosolic Zn, Cu, Ni or Cd in kidney. 相似文献
4.
《Aquaculture (Amsterdam, Netherlands)》2007,262(2-4):504-513
The objective of this study was to determine whether metallothionein (MT) expression was related to Cd accumulation in hard clams (Meretrix lusoria). We cloned clam MT. Then a specific primer for the hard clam was designed for MT mRNA measurements using real-time PCR. The hard clams were exposed to 50, 200, and 1000 μg/L cadmium (Cd) for 1, 3, 5, and 7 days, to determine the relationship between MT mRNA relative quantity (RQ) levels and Cd accumulation. The following results were obtained: (1) the cloned MT, consisting of 228 bp encoding a protein of 76 amino acids showed higher than 55% identity with the deduced amino acid sequence previously published for another bivalve. (2) Both MT mRNA expression and Cd accumulation appeared to be dose-responsive following cadmium treatment for 1, 3 and 5 days, respectively; however, no time-dependent responses were found. According to these results, MT mRNA expression levels can be used as an indicator to monitor the concentrations of Cd in aquaculture farms. 相似文献
5.
6.
镉胁迫对泥鳅金属硫蛋白基因表达的影响 总被引：3，自引：0，他引：3
采用实时荧光定量PCR(Real-time PCR)分析了不同浓度Cd2+(0、0.25、2.5 mg/L)胁迫24、48、72 h对泥鳅(Misgurnus anguillicaudatus)肝脏和鳃中金属硫蛋白(MT)基因相对表达水平的影响。结果表明,泥鳅肝脏和鳃MT基因的表达对外源Cd2+胁迫所表现出的反应存在差异,肝脏比鳃更为敏感;Cd2+浓度越高,胁迫时间越长,则肝脏和鳃中MT基因的相对表达水平越高。在受到Cd2+胁迫时,肝脏和鳃中大量表达MT,可降低Cd2+对机体造成的损伤。泥鳅MT基因可以作为监测水环境中镉污染的生物标志物之一。 相似文献
7.
重金属对水体的污染程度日益加重。人工湿地是一种人工建造的安全高效的生态处理技术,植物和基质都是其重要组成部分,其中的植物可以吸收污水中的营养物质、重金属及其他有毒、有害物质。为了研究植物对含Cd废水的处理效果,检验植物丰富度对人工湿地Cd去除能力的影响,探讨湿地植物对Cd的富集特性,本研究选用3种湿地植物灯心草（Juncaceae）、水葫芦（Eichhornia crassipes）和水芹菜（Oenanthe javanica）,按2种或3种混合方式,构建小型模拟人工湿地,测定分析其对低浓度（5 mg/L）含Cd废水中Cd的去除率、溶解氧（DO）浓度的影响及3种植物富集Cd含量、Cd在植物体内的亚细胞分布和化学形态。结果表明：水芹菜、灯芯草、水葫芦共同配植的湿地系统中,植物间发生协同作用,废水中DO浓度、Cd的去除率及3种植物对Cd的总富集量均最高;水芹菜的地下部分（根）富集量显著高于另外2种植物,灯芯草对Cd的抗性最强且转运系数最高,这2种植物属于优势湿地植物;Cd主要富集在3种植物细胞壁部分,以减轻对其它细胞器的毒害作用;植物体内的Cd以游离态为主,与有机配体结合较少,以减轻植物受害程度。在低浓度Cd污染下,水芹菜+灯芯草+水葫芦的组合对废水的净化效果最好,Cd去除率达到68.14%。 相似文献
8.
为探讨外源激素对半滑舌鳎性腺发育、体长增长及存活率的影响,用雌二醇和甲基睾酮分别处理半滑舌鳎幼鱼,各设200μg/L,400μg/L,500μg/L三个浓度进行浸浴处理,以乙醇处理作为阴性对照组,未做任何处理的作为空白对照组,统计各组存活率并在实验的不同时间段分别观察实验鱼的体长的变化;激素处理30 d后,每隔5 d每组取样5尾,通过组织学H.E染色观察各实验组幼鱼性腺的发育情况。结果表明,在甲基睾酮和雌二醇的诱导下,半滑舌鳎幼鱼的生长情况均受到一定程度的抑制,雌二醇在半滑舌鳎幼鱼发育早期对其卵巢发育具有一定的促进作用,而甲基睾酮则起到了抑制的作用。 相似文献
9.
10.
Acute effects of cadmium on liver phase I and phase II enzymes and metallothionein accumulation on sea bream Sparus aurata 总被引：1，自引：1，他引：0
Bouraoui Z Banni M Ghedira J Clerandeau C Guerbej H Narbonne JF Boussetta H 《Fish physiology and biochemistry》2008,34(3):201-207
This research was designed to study Sparus aurata (sea bream) biotransformation and detoxification responses to acute exposure to cadmium (Cd). Sexually immature gilthead
sea bream were treated by intraperitoneal injection of Cd chloride (200 μg kg−1) for 6, 12, 24 and 48 h. Cd accumulation was quantified in sea bream liver by graphite furnace atomic absorption spectroscopy
after the various exposure periods. The following biological responses were measured: (1) ethoxyresorufin-O-deethylase (EROD)
activity as phase I biotransformation parameter, (2) liver glutathione-S-transferase (GST) activity as a phase II conjugation
enzyme and metallothionein (MT) content as specific response to Cd contamination. Cd bioaccumulation in the liver resulted
in an increasing uptake up to 10.3 μg g−1 wet weight after 48 h of exposure. EROD showed a significant activation only after 6 h exposure and a return to control levels
after 12 h. GST revealed significant activation starting from 12 h exposure. MT accumulation in liver showed the same behavior
as GST activation. 相似文献
11.
J. Jebali M. Banni H. Guerbej E. A. Almeida A. Bannaoui H. Boussetta 《Fish physiology and biochemistry》2006,32(1):93-98
The potential use of acetylcholinesterase (AChE) and metallothionein (MT) responses as biomarker of organophosphorous (OPs)
and trace metal were assessed in fish Seriola dumerilli exposed to 0, 4, 6 mg/kg of malathion for 2, 7 and 13 days, and to 0, 50, 100, 250 μg/kg of Cd for 2 days. Brain AChE was
significantly inhibited after 2 and 7 days of malathion exposure, in a dose–response manner, but no inhibition was observed
after 13 days of exposure. When exposed to Cd for 2 days, S. dumerelli presented an increase in AChE activity at a concentration of 50 μg/kg, but a strong and dose-dependent AChE inhibition at
100 and 250 μg/kg. Cd treatment also caused a rapid increase in MTs concentration in liver, even at the lower concentration.
Our experiments indicate that the measurement of hepatic MT concentration and brain AChE activity in S. dumerilli would be useful biomarkers of OP and Cd exposure and/or effects. 相似文献
12.
13.
以褶牡蛎Crassostrea plicatula为研究对象,应用半静态双箱模型室内模拟了大、小两种规格褶牡蛎对重金属Cu、Cd的生物富集释放过程.通过对富集与释放阶段褶牡蛎体内重金属含量变化进行非线性拟合,得到了褶牡蛎对重金属Cu、Cd的生物富集曲线及富集动力学参数.结果表明,1)富集阶段褶牡蛎对Cu、Cd的生物富集系数BCF及吸收速率常数k1随着外部水体中重金属暴露浓度的增大而减少,理论平衡状态下生物体内重金属含量随外部水体中重金属暴露浓度的增大而增大;2)释放阶段褶牡蛎对重金属Cu、Cd的吸收速率常数k1随富集阶段外部水体中Cu、Cd暴露浓度的增大而减小,褶牡蛎体内Cu的生物学半衰期B1/2随富集阶段外部水体中Cu暴露浓度的增大而延长,Cd的生物学半衰期与Cd暴露浓度的关系无明显规律性;3)褶牡蛎对Cu的富集能力和排出能力均强于Cd;4)大规格褶牡蛎对Cu、Cd的富集能力均强于小规格,而褶牡蛎规格大小对于其体内Cu、Cd的排出作用的影响不显著. 相似文献
14.
饲料中Pb和Cd在中华绒螯蟹体内的吸收与释放特性 总被引：3，自引：0，他引：3
为获知饲料中重金属与中华绒螫蟹各组织间的富集与释放特性,应用生物富集双箱动力学模型,模拟中华绒螫蟹分别在Pb含量为10.21、22.01、40.81 mg/kg,Cd含量为1.78、2.80、4.48 mg/kg的饲料驯养过程中,其鳃、肝胰腺和肌肉对Pb和Cd的生物富集与释放特性,为Pb与Cd在中华绒螫蟹体内的分布、富集和迁移提供理论依据,为中华绒螫蟹安全生产提供指导。同时通过非线性拟合得到中华绒螫蟹对饲料中Pb和Cd的富集速率常数k_1、排出速率常数k_2、生物富集系数BCF、生物半衰期B_(1/2),富集平衡时生物体内Pb和Cd含量CAmax等动力学参数。结果显示:①中华绒螫蟹对饲料中的Pb和Cd具有明显的富集,蟹鳃、肝胰腺和肌肉中Pb的含量与富集时间和饲料中Pb的添加量表现出了很好的正相关,在富集的第48天,各组织器官中Pb的含量达到最大,在鳃中的含量分别为0.18、1.14、1.27和1.91 mg/kg;肝胰腺中含量分别为1.00、2.17、2.33和3.50 mg/kg;肌肉中含量分别为0.18、0.73、1.00和1.35 mg/kg。鳃和肝胰腺对饲料中Cd的吸收与Pb情况类似,在富集的第48天,4个饲料组蟹鳃中的浓度值均达到最高,分别为0.026、0.073、0.107和0.154mg/kg;肝胰腺除了在C组实验的第24天含量达到最高,为1.90mg/kg外,其他3组实验,在富集的第48天含量达到最高分别为0.33、1.05和1.24 mg/kg,C组在第48天的含量有所降低,为1.76 mg/kg。但是肌肉中Cd含量没有明显的规律。②中华绒螫蟹对Pb和Cd的生物富集和释放都较缓慢。达到平衡状态时,鳃、肝胰腺、肌肉各组织器官中Pb含量分别为1.07~1.69、4.87~4.95、0.79~1.28 mg/kg,鳃、肝胰腺中Cd含量分别为0.06~0.14和1.25~2.66 mg/kg。Pb和Cd在组织器官中的生物富集系数(BCF)范围分别为0.03~0.48和0.03~0.87,中华绒螫蟹对Cd的富集能力明显高于Pb;Pb和Cd在各组织器官的生物学半衰期(B_(1/2))范围分别为9~67 d和8~48 d。中华绒螫蟹对Pb的排除能力明显低于Cd。③Pb和Cd在中华绒螫蟹组织器官中的富集具有选择性,在经不同含量Pb和Cd的饲料驯养后得到统一含量分布规律:肝胰腺鳃肌肉。 相似文献
15.
利用双箱模型模拟了虾夷扇贝在混合暴露条件下富集、释放铅和镉的动力学特征,通过测定不同规格虾夷扇贝、不同组织富集、释放过程中铅和镉的含量并进行非线性拟合,获得不同生长阶段虾夷扇贝对铅和镉的生物富集系数BCF、吸收速率常数k1、释放速率常数k2、生物学半衰期B1/2以及不同组织中铅和镉的富集参数。结果显示,大、小两种规格虾夷扇贝对铅的BCF分别为1671、896,对镉的BCF分别为7433、1123;不同规格虾夷扇贝对铅、镉的BCF顺序为:大规格>小规格;相同规格虾夷扇贝BCF:镉>铅,表明虾夷扇贝对镉的富集能力强于铅;铅、镉的B1/2为:大规格>小规格,说明大规格的虾夷扇贝对铅、镉的代谢排出能力更强;铅在虾夷扇贝各组织中的富集顺序依次为:鳃>内脏团>闭壳肌,镉的富集顺序依次为:内脏团>鳃>闭壳肌。 相似文献
16.
Antibacterial and antiparasitic agents and a cysteine protease inhibitor (E‐64) were tested against Tetrahymena infection, a serious problem in guppy production worldwide. Chemicals were tested in vitro by a colorimetric assay for Tetrahymena survival. The most effective were niclosamide, albendazole and chloroquine, with 23%, 35% and 60% survival, respectively, following 2‐h exposure to 100 ppm. Longer incubation periods resulted in greater reductions in survival. Niclosamide was further studied in vivo at different dosages, administered orally to Tetrahymena‐infected guppies. Mortality rates were significantly lower in all treatment groups; in trial I, 30% and 33% mortality in 5 and 40 mg kg?1 niclosamide‐fed fish vs. 59% mortality in controls; in trial II, 35%, 13% and 10% in 50, 100 and 200 mg kg?1 niclosamide‐fed fish vs. 64% in controls. The effect of the cysteine protease inhibitor E64 was tested in tissue culture, by measuring histolytic activity of the parasite (Tet‐NI) on a guppy‐fin cell line, based on cell depletion. Tet‐NI feeding activity was significantly reduced following pretreatment with E‐64 relative to non‐treated Tet‐NI. E‐64‐pretreated Tet‐NI was injected i.p. into guppies: recorded mortality rates were significantly lower (35%) than that in non‐treated Tet‐NI (60%), suggesting inhibition of the parasite’s cysteine protease as a possible therapeutic approach. 相似文献
17.
厦门贝类养殖区沉积物中重金属的污染水平及其潜在生态危害 总被引：7，自引：0，他引：7
根据2005年4月和10月厦门贝类养殖区环境调查资料,着重对贝类养殖区表层沉积物中重金属的含量水平进行分析,并对贝类养殖区的表层沉积物进行质量评价及潜在生态危害评价.结果表明:厦门贝类养殖区沉积物中Cu、Pb、Cd、Zn、Hg、As的平均含量分别为20.0mg.kg-1,39.5mg.kg-1,0.07mg.kg-1,97.3mg.kg-1,0.05mg.kg-1,7.20mg.kg-1.其中同安湾北部和湾顶养殖区及西海域的杏林、东山养殖区,6种元素的含量均较高;位于同安湾的刘五店、澳头养殖区,含量均较低.沉积物质量评价结果表明,贝类养殖区沉积物中重金属的含量符合第一类海洋沉积物质量标准,属于较清洁水平.Hg、As和Cd的潜在生态危害系数大于Cu、Pb、Zn,整个养殖区沉积物中重金属为轻微生态危害,养殖环境良好. 相似文献
18.
采用RT-PCR方法扩增、克隆和鉴定了泥蚶(Tegillarca granosa)的金属硫蛋白(Metallothionein,MT)基因(TgMT)的开放阅读框(ORF)。基于金属硫蛋白氨基酸序列构建的系统进化树表明,泥蚶和魁蚶(Scapharca broughtonii)的亲缘关系最近。利用ORF序列,构建原核重组表达质粒。重组质粒经PCR、酶切鉴定及测序验证后转化大肠杆菌(Escherichia coli)BL21(DE3),经IPTG诱导,表达重组蛋白,重组蛋白的分子量约为28.3 kD。可溶性分析表明重组蛋白主要以可溶性形式存在。用His-tag柱亲和纯化重组蛋白,并利用重组蛋白制备了兔抗血清。Real-time PCR和Western blot实验表明,金属硫蛋白在泥蚶的各个组织中都有表达,并且在消化腺中的表达量最高。采用激光共聚焦显微镜,对泥蚶的消化腺进行免疫组化定位分析,发现泥蚶的MT主要存在于消化腺腺管上皮细胞的胞质中。泥蚶MT的克隆和表达研究为进一步研究该蛋白在环境监测中的作用、探讨细胞解毒的分子生物学机制奠定了基础。 相似文献
19.
J. Ghedira J. Jebali Z. Bouraoui M. Banni H. Guerbej H. Boussetta 《Fish physiology and biochemistry》2010,36(1):101-107
The levels of metallothionein (MT), a biomarker of metal exposure, and of Cd and Cu, known as MT inducers, were investigated
in Sparus aurata intraperitoneally injected with 500 μg/kg of Cu and Cd for 2 days. MT and metal concentrations (Cd and Cu) were determined
in liver, gills and kidney. MT levels were significantly increased in all investigated tissues, with the highest value in
liver of Cu as Cd-treated fishes (3.56-fold and 3.3- fold, respectively). Metal concentrations were statistically different
between all tissues. Highest metal concentrations were in the liver. The higher metal concentrations and MT induction levels
support the main role of MT in metal homeostasis and detoxification. 相似文献
20.
分析了不同浓度印染污水对银鲫(Carassius auratus)的生殖相关指标和金属硫蛋白(MT)的影响.设计1个对照组和2个试验组,对照组采用天然的水库水,试验组分别用浓度为0.1％和0.2％的印染污水养殖银鲫,每组3个平行,每个平行随机放入50尾银鲫,试验期为4周.结果表明,养殖4周后,0.1％印染污水组银鲫的肝体指数和血清卵黄蛋白原(VTG)水平显著上升(P＜0.05),0.2％印染污水组银鲫的血清VTG水平显著低于对照组(P＜0.05),印染污水对银鲫性腺指数没有影响.0.1％印染污水组银鲫在第2、3、4周,肝脏MT水平均显著高于对照组(P＜0.05),0.2％印染污水组银鲫肝脏MT水平在第3周时显著升高(P＜0.05),印染污水对银鲫肾脏MT水平没有影响(P＞0.05);表明印染污水能够影响银鲫繁殖功能和组织MT的水平. 相似文献