排序方式： 共有16条查询结果，搜索用时 15 毫秒
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Florence Geret Angela Serafim Luisa Barreira Maria Joo Bebianno 《Marine environmental research》2002,54(3-5)
Copper (Cu) is an essential element for biological systems, however, when present in excess, is toxic. Metallothioneins can play an important role in Cu homeostasis and detoxification. Moreover, Cu can catalyse the production of toxic hydroxyl radicals that cause lipid peroxidation but defence systems in the cells can limit the oxidative damage. The present study was performed to investigate the effect of three Cu concentrations (0.5, 2.5 and 25 μg l−1) on the response of antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT), selenium-dependent glutathion peroxidase and total glutathion peroxidase), total proteins, metallothioneins (MT), malondialdehyde (MDA) concentrations in the gills of the clam, Ruditapes decussatus. The activity of antioxidant enzymes and total proteins, MT and MDA concentrations were measured in the gills of the clams after 1, 3, 7, 14, 21 and 28 days of Cu exposure. Results indicate that Cu only induces an imbalance in the oxygen metabolism during the first week of Cu exposure due to a decrease in mitochondrial SOD and CAT, selenium-dependent and total glutathion peroxidase activities. Cu also causes lipid peroxidation, measured by the MDA formation, that was Cu dependent. In the gills of clams exposed to 25 μg Cu/l, the excess of Cu triggers the induction of MT synthesis after 3 days of exposure. 相似文献
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通过腹腔注射沙蜇刺胞毒素于吗啡依赖型戒断小鼠,检测小鼠肝脏、肾脏、心脏和脑的SOD、CAT、NOS酶活力和MDA含量的变化情况,并进行统计学分析,研究沙蜇刺胞毒素对纳洛酮催促吗啡依赖小鼠的戒断作用。结果表明,沙蜇刺胞毒素对吗啡依赖小鼠各组织酶活力的恢复有明显的作用。出现戒断症状的小鼠肝脏的SOD和CAT活性比对照组明显降低,注射沙蜇刺胞毒素后两种酶活性逐渐恢复,但还是略低于对照组。相反MDA含量吗啡组最高,沙蜇刺胞毒素Ⅰ次之,沙蜇刺胞毒素Ⅱ最低。通过小鼠戒断前后肝脏、肾脏、心脏、脑等组织中SOD和CAT活性酶的检测结果,证明了沙蜇刺胞毒素可改善小鼠由于吗啡作用而产生的机体的抗性下降、逐渐恢复正常生理功能,能抑制吗啡依赖小鼠戒断反应的发生,对吗啡依赖小鼠的戒断起到积极的治疗作用。 相似文献
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Pampanin DM Camus L Gomiero A Marangon I Volpato E Nasci C 《Marine pollution bulletin》2005,50(12):512-1557
The aim of this study was to evaluate the susceptibility to pollutant mediated oxidative stress of the Mediterranean mussel Mytilus galloprovincialis in the Venice lagoon (Italy).
In June 2003, mussels from a farm were transplanted to eight sites in the lagoon for five weeks. Oxidative stress responses were measured by: (i) total oxyradical scavenging capacity (TOSC) assay, for an overall evaluation of the oxidative stress response capability; (ii) catalase (CAT), as a key enzyme involved in the antioxidant defence system; (iii) malondialdehyde (MDA), as an indicator of lipid peroxidation, to evaluate an oxidative damage; (iv) metallothioneins (MTs), as they play a role in the antioxidant defence.
The TOSC analysis revealed a reduced capability to eliminate: (i) peroxyl radical in mussels transplanted at Palude della Rosa, Valle Millecampi and Chioggia; (ii) hydroxyl radical at Campalto and Valle Millecampi; (iii) peroxynitrite at Valle Millecampi.
Inhibition in CAT activity, observed in all the monitored sites, confirms the presence of an oxidative pressure in transplanted mussels.
In addition, Pearson correlation analysis was performed in order to observe possible links between the various parameters. The PCA was a powerful tool to discriminate impacted sites, suggesting that the mussels transplanted throughout the Venice lagoon were subjected to different levels of oxidative pressure. Furthermore, it provided an easy and useful tool to summarize the obtained results. 相似文献
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栉孔扇贝血淋巴中超氧化物歧化酶和过氧化氨酶活性及其性质的研究 总被引：2，自引：0，他引：2
于１９９７年１０月－１９９８年１月,从胶州湾贝类养殖场购买栉孔扇贝,分别采用邻苯三酚自氧化法和过氧化氢法测定了其血细胞和血清中的超氧化物歧化酶（ＳＯＤ）和过氧化氢酶（ＣＡＴ）的活力,并对ＳＯＤ类型的鉴别区分、ＳＯＤ和ＣＡＴ的热稳定性以及温度对ＳＯＤ和ＣＡＴ活力的影响进行研究。结果表明,血细胞中ＳＯＤ和 ＣＡＴ活力分别为３１２．７Ｕ和 １２４．４Ｕ,血清中ＳＯＤ和ＣＡＴ活力分别为１０２．３Ｕ和７３．８Ｕ;冻存１０ｄ后,血清中ＳＯＤ的活力丧失２４．６％,而ＣＡＴ的活力丧失４０．８％;血细胞中ＣｕＺｎ－ＳＯＤ和Ｍｎ－ＳＯＤ的活力分别为１９３．４Ｕ和８２．３Ｕ,血清中仅存在ＣｕＺｎ－ＳＯＤ活性;血清中ＳＯＤ的热稳定性很高,在８０℃下保温３０ｍｉｎ后,酶活力仍很高,而ＣＡＴ的热稳定性较低;血清中的ＳＯＤ和ＣＡＴ的最适温度分别为５０℃和４５℃。 相似文献
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中华绒螯蟹( Eriocheir sinensis) 幼蟹上岸病的免疫学研究 总被引：4，自引：2，他引：4
对患上岸病幼蟹和正常幼蟹体内的超氧化物歧化酶 (SOD)、过氧化氢酶 (CAT)、溶菌酶活性及丙二醛含量等几项免疫学指标的测定和比较 ,探讨幼蟹上岸死亡疾病的病因。结果表明 ,患病幼蟹自由基的代谢出现紊乱 ,清除自由基的能力较正常幼蟹显著下降 ,其中超氧化物歧化酶及过氧化氢酶的活性极显著低于正常幼蟹 (P <0 .0 1 )。而在反映自由基损伤程度的丙二醛含量上 ,患病幼蟹极显著高于正常幼蟹 (P <0 .0 1 ) ;患病幼蟹的溶菌酶活性显著低于对照组 (P <0 .0 5 )。研究表明 ,大量自由基的积累对幼蟹的组织或器官造成了损伤 ,同时也降低了机体的免疫能力 ,从而导致了幼蟹上岸病的发生 相似文献
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The aim of the present work was to determine the activities of selected antioxidant enzymes (SOD, Se-GPX, CAT) in two species of bivalves, Scapharca inaequivalvis and Tapes philippinarum, from two sites of the lagoon of Venice that are characterized by different pO(2) (Marghera and Chioggia). The specimens were collected at four times during a 1-year period. In the two species studied, enzyme activities were found to be present in both digestive glands and gills, but with some species-specific differences that may also represent a different adaptation to seasonal variations. The presence of high SOD activities in the gills of both species may be related to their physiological role in respiration. Scapharca inaequivalvis is less sensitive than T. philippinarum to environmental changes, perhaps due to the presence of hemoglobins in this species. Moreover, in the digestive gland of T. philippinarum we found a significant negative correlation between the activities of SOD and GPX that may indicate the presence of oxidative stress. Some correlations between temperature/dissolved oxygen and antioxidant enzyme activity were present in specimens sampled in Marghera. Only GPX adequately responded to changes in dissolved oxygen and temperature, while the decrease in the activity of SOD and CAT in winter may be directly responsible for an enhanced susceptibility of mussels to oxidative stress during this period. We can conclude that the observed differences between Chioggia and Marghera are due to different concentrations of dissolved oxygen. Marghera is an appropriate location to study seasonal variations in water temperature. In fact, in this site, the differences between hot and cold months are quite evident. 相似文献
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原油污染对栉孔扇贝抗氧化酶活性的影响 总被引：2，自引：0，他引：2
以原油水溶性成分(water soluble fraction of crude oil,WSF)为污染物,采用暴露实验法,研究了栉孔扇贝(Chlamys farreri)鳃和消化腺组织中超氧化物歧化酶(Superoxide Dismutase,SOD)和过氧化氢酶(Catalase,CAT)活性的变化.结果表明,WSF污染下,鳃和消化腺组织SOD和CAT酶活性随暴露时间增加一般表现为降低-升高-降低的趋势,酶活性达到最高的时间随浓度不同而变化.第1天时消化腺SOD在0.08 mg/L浓度下被诱导,而后随时间增加表现为抑制效应;浓度为0.21和0.88 mg/L时消化腺SOD酶活性被抑制,随暴露时间延长而活性增加.暴露时间为4d时,石油烃浓度在0.08和0.88 mg/L时鳃组织SOD酶活性均被抑制,而浓度为0.21 mg/L时被诱导.消化腺和鳃组织SOD可以作为扇贝被污染胁迫的指标. 相似文献
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The effects of BDE-47 on the growth and antioxidative responses of the seedlings of Kandelia obovata (Ko) and Avicennia marina (Am) were compared in an 8-week hydroponic culture spiked with different levels of BDE-47, 0.1, 1, 5 and 10 mg l−1. The two highest BDE-47 levels significantly suppressed the growth and increased the activities of three antioxidative enzymes, superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), of Ko in week 1. However, SOD and POD activities at high levels of BDE-47 became lower than the control in week 8. On the contrary, growth of Am was not affected at all contamination levels, and the activities of three enzymes were enhanced by BDE-47 in weeks 1 and 4, but such stimulatory effect became insignificant in week 8. Avicennia was more tolerant to BDE-47 toxicity than Kandelia, as its antioxidative enzymes could better counter-balance the oxidative stress caused by BDE-47. 相似文献