苯并（a）芘对大弹涂鱼肝脏谷胱甘肽过氧化物酶活性的影响

研究大弹涂鱼（Ｂｏｌｅｏｐｈｔｈａｌｍｕｓ ｐｅｃｔｉｎｉｒｏｓｔｒｉｓ）暴露于０．０５、０．２０和０．５０ｍｇ／Ｌ不同质量浓度苯并（ａ）芘（ＢａＰ）溶液中１周，其肝脏谷胱甘肽过氧化物酶（ＧＰｘ）活性的变化。结果显示：０．５ｍｇ／Ｌ ＢａＰ组中，随暴露时间的延长，大弹涂鱼肝脏ＧＰｘ活性被显著抑制（Ｐ≤０．０５）；暴露３ｄ，随ＢａＰ浓度的增加，ＧＰｘ活性显著降低（Ｐ≤０．０５），表明高剂量的ＢａＰ可     

力竭追赶训练对中华倒刺鲃自由基清除能力的影响

在(25±1)℃条件下,设置静水对照组(C组)、力竭追赶训练1次/d组(E1组)、力竭追赶训练2次/d组(E2组),研究了每日不同训练次数的力竭追赶训练对中华倒刺鲃(Spinibarbus sinensis)(46.84 g±2.50 g,13.73cm±0.22 cm)生长和自由基代谢相关指标的影响,训练周期为21 d。结果显示,中华倒刺鲃体质量特定生长率、肥满度和肝指数均比对照组有极显著降低;中华倒刺鲃肝脏和白肌抗氧化酶对力竭训练产生了一定适应性,但超氧化歧化物酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)和过氧化氢酶(CAT)对力竭训练的敏感性不同;力竭训练对肝脏和白肌总抗氧化能力(T-AOC)无显著影响;在肝脏和白肌丙二醛(MDA)方面,E2组>C组>E1组;E2组血清谷丙转氨酶(ALT)活性显著高于对照组和E1组,而3组血清肌酸激酶(CK)活性差异不显著。结果表明,力竭追赶训练对生长具有明显抑制性,并且对中华倒刺鲃脂质过氧化反应有类似"毒物兴奋效应",肝脏和白肌对其表现出不同的抗氧化调节机制。     

苯并_a_芘对大弹涂鱼肝脏芳烃羟化酶活性的影响

研究了苯并(a)芘(BaP)胁迫下大弹涂鱼肝脏芳烃羟化酶(AHH)活性的变化,结果显示BaP对大弹涂鱼肝脏AHH活性总体表现为显著的诱导作用(P＜0.01),其中BaP暴露的浓度及时间是影响AHH活性的重要因素.0.05mg@L-1浓度的BaP暴露对AHH活性无显著影响,而0.2mg@L-1和0.5mg@L-1浓度组AHH活性则显著被诱导(P＜0.01).随着暴污时间的延长,0.2mg@L-1浓度组AHH活性被显著诱导(P＜0.01),而0.5mg@L-1组AHH活性则相对稳定.对AHH活性变化的剂量-效应关系进行回归分析的结果表明,0.5mg@L-1浓度组暴露7d时,AHH活性受到一定程度的抑制.污染解除后,0.5mg@L-1浓度组AHH活性显著降低,恢复至与对照组相近,表明大弹涂鱼肝脏仍具有较强的生理调节机能,同时也表明AHH活性可及时反映环境中BaP的水平.以上这些结果表明AHH适于作为大弹涂鱼受BaP胁迫的生物指标.     

镉对大弹涂鱼肝脏超氧化物歧化酶活性的影响

研究了不同质量浓度镉对大弹涂鱼肝脏超氧化物歧化酶SOD活性的影响。试验结果表明,当曝露于质量浓度为0.05、0.5 mg/L镉中3 d时,大弹涂鱼肝脏SOD活性被显著诱导,当曝露于质量浓度为5.0 mg/L镉中1 d时即被显著诱导;随着曝露时间的延长,各含量组肝脏SOD的活性均不同程度下降,但中低质量浓度条件下仍表现为诱导,而高质量浓度组SOD活性10 d后即明显下降,呈现中毒抑制现象。     

盐酸恩诺沙星对杂交鲟幼鱼肝脏抗氧化酶活性的影响

在水温(17.5±0.5)℃和盐酸恩诺沙星质量浓度1.56、6.25、25.00 mg/L和100.00 mg/L下,采用生化和半静态亚急性毒性方法研究了盐酸恩诺沙星对体质量(10.26±2.37)g杂交鲟(施氏鲟♀×西伯利亚鲟♂)幼鱼肝脏中超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶活性的影响。试验结果显示,盐酸恩诺沙星对杂交鲟幼鱼96h半致死质量浓度100.00mg/L,属于低毒。各试验剂量盐酸恩诺沙星均显著影响杂交鲟幼鱼肝脏超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶活性(P0.05),且随时间的延长超氧化物歧化酶、过氧化氢酶和谷胱甘肽过氧化物酶活性均呈先升后降变化,即先诱导后抑制,但3种抗氧化酶活性被诱导的程度在时间上具有差异性。低质量浓度组(1.56、6.25mg/L)酶活性峰值出现较晚,高质量浓度组(25.00、100.00mg/L)酶活性峰值出现较早,表明高质量浓度下鱼体首先出现氧化应激反应,盐酸恩诺沙星引起的酶活性变化与暴露质量浓度和时间有一定相关性。     

重金属镉胁迫对大弹涂鱼肝脏黄嘌呤氧化酶活性的影响

研究了在重金属镉胁迫条件下,大弹涂鱼(Boleophthalmuspectinirostris)肝脏黄嘌呤氧化酶活性的变化。重金属镉胁迫12h时0·5mg/LCd2 组XOD酶活性和对照组比较显著升高(P<0·05);胁迫24h时,大弹涂鱼0·05mg/LCd2 组肝脏的XOD酶活性和对照组比较极显著升高(P<0·01),而0·5mg/LCd2 组酶活性结果却降低;恢复3d时0·5mg/LCd2 又极显著升高(P<0·01)。在镉胁迫解除5d时,3个浓度组的酶活性均极显著降低(P<0·01),其中0·05mg/LCd2 组和0·5mg/LCd2 组的酶活性和对照组酶活性比较无显著差异(P>0·05),5mg/LCd2 组的酶活性极显著低于对照组的酶活性(P<0·01)。实验结果表明,大弹涂鱼肝脏黄嘌呤氧化酶活性对水体中镉污染敏感,有可能用做海洋环境污染的生物标记。     

大弹涂鱼急性镉中毒对脾脏4种同工酶表达的影响

用聚丙烯酰胺凝胶(PAGE)电泳法研究了镉对大弹涂鱼(Boleophthalmus pectinirostris)脾脏的酯酶(EST)、过氧化物酶(POD)、苹果酸脱氢酶(MDH)和超氧化物歧化酶(SOD)表达的影响。结果表明,在急性中毒条件下,与空白对照组相比,25、50和75mg／L 3个处理组的4种同工酶均有特异性酶带出现,各种酶活性也有显著变化。本文探讨了急性镉中毒对大弹涂鱼脾脏4种同工酶表达的影响,以及大弹涂鱼脾脏的同工酶标记用作海洋环境生态毒理学指标的可行性。     

乙草胺对泥鳅肝脏乙酰胆碱酯酶和谷胱甘肽硫转移酶的影响

用急性染毒法研究了5种不同浓度、不同处理时间的乙草胺对泥鳅(Misgurnus anguillicaudatus)肝脏乙酰胆碱酯酶(AChE)和谷胱甘肽硫转移酶(GST)活性的影响。结果表明,不同浓度的乙草胺处理对泥鳅肝脏中AChE均起抑制作用。低浓度的乙草胺处理对泥鳅肝脏中GST活性起诱导作用,而高浓度则起抑制作用。     

大弹涂鱼白细胞介素-8基因分子进化及不同病原体刺激对其表达的影响

实验从大弹涂鱼皮肤组织转录组中筛选出大弹涂鱼IL-8基因,并分析了其序列特征,构建了系统发生树,评估了IL-8基因在健康个体不同组织中的表达差异,以及在不同病原体刺激下IL-8基因在机体主要免疫器官肝脏和脾脏中的表达情况。结果显示,该基因的开放阅读框由306个碱基组成,编码101个氨基酸残基,包含典型的由18个氨基酸残基组成的信号肽,和1个由62个氨基酸残基组成的SCY结构域,该结构域还包含了4个保守的半胱氨酸残基,分别为Cys-30、Cys-32、Cys-57和Cys-73。大弹涂鱼IL-8氨基酸序列中的受体结合位点基序ELR (Glu-Leu-Arg)被Asn-Ser-His (NSH)取代,系统进化分析表明,纯化选择影响了鱼类该基序的多样性,且IL-8基因在大弹涂鱼乃至硬骨鱼中不可取代。荧光定量实验结果显示,IL-8基因在大弹涂鱼的健康组织中广泛表达,在鳃和脑中表达量最高。细菌和poly(I∶C)注射实验表明,在受到感染后,肝、脾和脑组织中IL-8的表达量均上调,说明IL-8基因在大弹涂鱼肝、脾和脑组织的炎性反应和免疫应答中起到了重要作用,为大弹涂鱼免疫基因的后续研究提供了参考。     

急性升温胁迫与恢复对葛氏鲈塘鳢抗氧化酶活性的影响

将体质量(13.41±6.31) g的葛氏鲈塘鳢分为3组,饲养在80 cm×60 cm×40 cm的玻璃水族箱中。对照组水温为17℃;渐变升温组的升温速率为1℃/d;急性升温组试验鱼直接由17℃水族箱转至31℃水族箱中。两个试验组水温恒定在31℃后,测定各组葛氏鲈塘鳢的死亡率,肝脏、脑和肌肉中抗氧化酶(超氧化物歧化酶、过氧化氢酶、谷胱甘肽过氧化物酶)的活性及丙二醛的浓度,以深入了解急性升温胁迫对葛氏鲈塘鳢抗氧化能力的影响,为葛氏鲈塘鳢的人工养殖提供参考。试验结果显示,急性升温组葛氏鲈塘鳢的死亡率显著高于渐变升温组(P0.05);肝脏和脑的抗氧化酶活性升高,6 h后脑中的超氧化物歧化酶和谷胱甘肽过氧化物酶活性显著高于渐变升温组(P0.05),恢复至17℃过程中,超氧化物歧化酶和谷胱甘肽过氧化物酶活性显著低于对照组(P0.05);肌肉中超氧化物歧化酶活性升高,在12 h时显著高于渐变升温组(P0.05);1 h内肝脏中丙二醛浓度显著高于对照组(P0.05),脑中丙二醛浓度显著高于对照组和渐变升温组(P0.05),肌肉中丙二醛浓度显著高于渐变升温组(P0.05),而恢复过程中脑丙二醛浓度显著高于对照组(P0.05)。试验结果表明,长时间的高温胁迫后,肝脏和脑组织受损伤无法恢复,而肌肉比肝脏和脑组织更能适应急性升温变化。脑中谷胱甘肽过氧化物酶最先响应急性升温的氧化损伤,随后超氧化物歧化酶和过氧化氢酶的活性升高抑制谷胱甘肽过氧化物酶活性。渐变升温下葛氏鲈塘鳢的存活时间更长。     

饥饿及恢复生长对方斑东风螺抗氧化体系的影响

在(25.8±1.7)℃条件下,测定了方斑东风螺(Babylonia areolata)不同饥饿期(7d、15d、25d、40d)后再投喂(30d)过程中足肌、肝胰脏的抗氧化体系相关指标变化。结果显示,分别饥饿25d和40d时幼螺两组织丙二醛(MDA)含量较对照组均显著升高;饥饿25d前,超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GPx)活力较对照组逐渐增强,当禁食达40d时却显著减弱;谷胱甘肽硫转移酶(GST)活力饥饿状态下先略上升后下降,肝胰脏、足肌中分别于饥饿25d和40d时显著降低;谷胱甘肽还原酶(GR)活力及谷胱甘肽(GSH)含量随禁食延长均呈下降趋势。恢复生长后,除饥饿40d组GR活力及肝胰脏MDA水平较对照呈差异显著外,该组其余指标及其他各处理组相应指标均恢复至或接近对照组水平。结果表明,饥饿胁迫下螺体抗氧化体系虽被激活,但仍处于一定的氧化应激状态,提示幼螺养成中禁食时间不宜超过25d,且SOD、CAT与GPx活性可作为螺体饥饿胁迫状态的指示参数。     

不同温度下BDE-209对草鱼离体肝脏组织的毒性效应

为探讨不同温度条件下十溴联苯醚(BDE-209)对鱼类的毒性影响,以草鱼(Ctenopharyngodon idellus)幼鱼离体肝脏组织为试验材料,在肝脏组织匀浆液中加入浓度为0.00、0.04、4.00、400.00μg/L的BDE-209,并将其分别置于低温(15℃)、常温(25℃)、高温(35℃)中水浴60 min,然后检测肝脏组织中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽还原酶(GR)的活性以及丙二醛(MDA)的含量。结果显示:低温时各浓度组BDE-209诱导下的SOD、CAT、GR活性与对照组没有显著性差异;常温时BDE-209对SOD、CAT、GR活性具有低浓度诱导高浓度抑制的现象,高温时BDE-209对肝脏组织中CAT、SOD、GR活性造成明显的抑制效应,MDA在不同温度条件下其含量都随BDE-209暴露浓度的升高而升高。研究结果表明:在一定的温度范围内,温度越高,BDE-209对鱼体肝脏组织造成的氧化损伤越大。     

Dietary phosphorus prevents oxidative damage and increases antioxidant enzyme activities in intestine and hepatopancreas of juvenile Jian carp

This study was conducted to investigate the effect of dietary phosphorus on the intestine and hepatopancreas antioxidant capacity of juvenile Jian carp (Cyprinus carpio var. Jian). Jian carp, with an average initial weight of 7.17 ± 0.01 g, were fed with diets containing graded concentrations of available phosphorus, namely 1.7 (control), 3.6, 5.5, 7.3, 9.2 and 11.0 g kg^?1 diet for 9 weeks. Results showed that, in intestine and hepatopancreas, content of malondialdehyde (MDA), protein carbonyl (PC) and glutathione (GSH), capacity of anti‐superoxide anion (ASA) and anti‐hydroxyl radical (AHR), and glutathione reductase (GR), catalase (CAT), glutathione S‐transferase (GST), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were significantly affected by dietary phosphorus levels (P < 0.05). Regression analysis showed that significant quadratic responses occurred in MDA content and ASA, GST, GPx and AHR activities in intestine, GSH content and CAT and SOD activities in hepatopancreas (P < 0.05). These results indicate that optimal level of dietary phosphorus prevented oxidative damage and increased antioxidant enzyme activities in the intestine and hepatopancreas of juvenile Jian carp. The phosphorus requirement estimated from MDA using quadratic regression analysis was 5.7 g kg^?1 diet.     

Oxidative stress parameters during starvation and refeeding periods in Adriatic sturgeon (Acipenser naccarii) and rainbow trout (Oncorhynchus mykiss)

This work analyses the changes in the redox balance in two fish species: Adriatic sturgeon ( Acipenser naccarii ) and rainbow trout ( Oncorhynchus mykiss ) during starvation and refeeding period. The starvation period raised the lipid peroxidation (thiobarbituric-acid-reacting substances) levels in liver and blood, while a decline occurred in the antioxidant enzymatic activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GR) in both fish species. In liver, after the refeeding period, SOD activity recovered in both species, whereas CAT activity recovered only in trout. Furthermore, in both tissues of the two species, the lipid peroxidation levels remained high after 2 months of refeeding. In white muscle and heart, the lipid peroxidation levels indicate that these tissues did not undergo oxidative stress during the 72-day period. During starvation, in the muscle of both fish the fall in the lipid peroxidation level coincided with a rise in CAT, GPX and GR. The refeeding period in this tissue raised the lipid peroxidation level, and the enzymatic activities reached the values of the first point of starvation. In heart, no oxidative damage was detected during starvation in either species. The CAT and SOD activities increased during the starvation period only in trout.     

Influence of dietary zinc on lipid peroxidation,protein oxidation and antioxidant defence of juvenile Jian carp (Cyprinus carpio var. Jian)

This study was conducted to study the effects of dietary zinc on lipid peroxidation, protein oxidation and antioxidant defence of juvenile Jian carp (Cyprinus carpio var. Jian) by feeding fish with increasing levels of zinc (15.3, 26.9, 40.8, 58.2, 68.9 and 92.5 mg Zn kg^?1) for 6 weeks. Results indicated that malondialdehyde (MDA) content and protein carbonyls (PC) in serum were the highest in fish fed diet containing 15.3 mg zinc kg^?1 diet (P < 0.05). Serum antisuperoxide anion (ASA), superoxide dismutase (SOD), glutathione peroxidase (GSH‐Px), glutathione reductase (GR) activities and glutathione (GSH) content were improved with increasing dietary zinc levels up to 40.8 mg zinc kg^?1 diet (P < 0.05) and levelled off (P > 0.05). Serum antihydroxy radical (AHR), catalase (CAT) and glutathione‐S‐transferase (GST) activities followed the similar pattern to that observed in ASA. The MDA and PC levels, ASA, AHR, SOD, CAT, GPx, GR, GST activities and GSH content in intestine, hepatosomatic and muscle tissue followed the similar pattern to that observed in serum. The present results indicated that zinc decreased lipid peroxidation and protein oxidation and improved antioxidant defence in fish.     

Effects of fish size on the response of antioxidant systems of Oreochromis niloticus following metal exposures

The size of a fish is an important factor in its physiology, and metal uptake is affected by animal physiology. In this study, small and large tilapias (Oreochromis niloticus) differing approximately twofold in length and fivefold in weight were compared for their antioxidant response. Both groups were exposed to Cu or Cr (1.0 μg/mL) in a freshwater (?80 mg CaCO₃/L, conductivity 1.77 mS/cm) using 2 exposure protocols (20 μM for 48 h and 10 μM for 6 days). Following the exposures, the antioxidant enzyme activities (superoxide dismutase, SOD; catalase, CAT; glutathione peroxidase, GPX; glutathione reductase, GR and glutathione S-transferase, GST) and glutathione (GSH) levels were measured in the liver of fish. Results showed that small fish was affected from exposure conditions much more than large ones as their antioxidant parameters significantly decreased even in controls. Metal exposures of small fish caused significant increases in SOD and CAT activity in acute Cu or Cr exposures. Subchronic Cr exposure of small fish also caused significant increases in CAT, GPx and GST activities, while there was no significant change in Cu-exposed ones. Large fish, however, showed different antioxidant responses as their levels mostly decreased. This study demonstrated that the response of antioxidant system in the liver of tilapia varied in relation to fish sizes and emphasized using different size groups in environmental monitoring and also in evaluation of fish biomarkers.     

pH水平和昼夜变化对池塘养殖凡纳滨对虾成活率的影响

为评价不同pH水平和昼夜变化幅度对凡纳滨对虾成活率的影响,采用单因素实验设计,实验Ⅰ设4个pH水平:6.6(P1)、7.6(P2)、8.6(P3)和9.6(P4),以温室养殖池塘内的平均pH水平(8.2)为对照(P0);实验Ⅱ设3个pH昼夜变化幅度:7.5～8.2(PV1)、7.5～9.5(PV2)和7.5～10.0(PV3),以养殖池塘的平均pH昼夜变化幅度(7.5～8.7)为对照(PV0)。结果显示,环境pH水平可显著影响对虾成活率、血淋巴颗粒细胞数以及血淋巴中超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、谷胱甘肽还原酶(GR)、过氧化氢酶(CAT)、酚氧化酶(PO)和诱导型一氧化氮合酶(iNOS)的活性。P4水槽内对虾成活率显著低于P0、P1、P2和P3水槽,同时其血淋巴SOD、GSH-Px、GR、CAT、PO和iNOS的活性较后者不同程度地下降。pH昼夜变化幅度可显著影响对虾成活率、血淋巴SOD、GSH-Px、GR和CAT活性,但对血淋巴谷胱甘肽含量无显著影响。PV2和PV3水槽内对虾成活率显著低于PV0和PV1水槽,同时其血淋巴SOD、GSH-Px、GR和CAT活性较后者不同程度地降低。研究表明,环境pH水平及昼夜变化幅度可显著影响凡纳滨对虾的成活率。鉴于对虾死亡率变化伴随血淋巴SOD、GSH-Px、CAT和PO活性的变化,初步认为对虾死亡与pH胁迫产生的应激有关。因此,调控pH应是对虾池塘养殖水质管理中的一项重要措施。     

Assessment of tissue-specific effect of cadmium on antioxidant defense system and lipid peroxidation in freshwater murrel, Channa punctatus

The effects of different concentrations of cadmium chloride on the extent of lipid peroxidation (LPO) and alterations in the antioxidant enzyme activities were studied in liver, kidney and gill tissues of freshwater murrel, Channa punctatus. The fish specimens were exposed to 6.7, 13.4 and 20.1 mg l⁻¹ sublethal concentrations of cadmium chloride and the oxidative stress was assessed after 24, 48, 72 and 96 h post-exposure. The biomarkers selected for the study were thiobarbituric acid reactive substances for assessing the extent of lipid peroxidation and antioxidant defense system such as reduced glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GP_X), glutathione-S-transferase (GST), catalase (CAT) and superoxide dismutase (SOD) activities. In general, the cadmium exposure elevated the LPO in subject tissues of treated group and modulated the activities of GPx, GST, SOD, CAT, GR and level of GSH after given exposure as compared to the control. All enzymes activities, except CAT (in kidney and gills), and amount of LPO elevated significantly (P < 0.05) in treated group with respect to control in all tissues, while significant difference was not observed between the exposed concentrations and within exposure duration. The results indicated that increase in LPO level and the fluctuation in antioxidant defense system in fish could be due to cadmium-induced increase in the production of reactive oxygen species (ROS). The potential role of these parameters as biomarkers of heavy metal pollution in aquatic system is discussed.     

Dietary ginger administration attenuates oxidative stress and immunosuppression caused by oxytetracycline in rainbow trout (Oncorhynchus mykiss)

In the present study, potential ameliorative effects of dietary ginger (GN) were investigated on antioxidant and immune responses of rainbow trout (Oncorhynchus mykiss) during oxytetracycline (OX) administration. As a 2 × 3 factorial design, the fish were orally treated with OX (a daily dose of 100 mg/kg) and GN (either 10 or 20 g/kg diet) for 10 days. Then, blood samples were taken from each treatment to monitor plasma lysozyme, complement (ACH50), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione‐S‐transferase (GST) activities, and reduced glutathione (GSH), malondialdehyde (MDA), total immunoglobulin (Ig) and globulin levels. OX treatment significantly decreased SOD (30%), GPx, (10%) and lysozyme (23%) activities, and GSH (19%) levels; however, it increased GST (16%) activity and MDA (28%) levels. Ten grams GN per kg levels significantly decreased SOD (35%), CAT (13%), GST (20%) and MDA (30%), but increased GSH (30%), lysozyme (48%) and globulin (16%). Twenty grams GN per kg diet significantly decreased SOD (26%) and MDA (17%), but increased lysozyme (31%) levels. Interaction effects of dietary GN and OX were observed on plasma MDA and GPx levels, as 10 g GN per kg diet prevented the OTC‐induced changes in these parameters. Moreover, 20 g GN per kg diet prevented the OX‐induced change in GPx activity and mitigated the MDA elevation by 20%. It is concluded that GN administration at 10 g/kg diet is beneficial in mitigating oxidative stress and immunosuppression of rainbow trout during OX administration.