草鱼同工酶发育遗传学研究——Ⅰ.不同组织器官的同工酶分析

采用垂直淀粉凝胶电泳及特异性组织化学染色技术,研究了草鱼成体脑、眼、心、肾、肌、肝等6种组织中的6种同工酶系统(LDH、MDH、GDH、ADH、LDH、EST)的分化表达谱式。结果表明,草鱼的同工酶系统具有明显的组织特异性。与绝大多数硬骨鱼类相比,草鱼的LDH、m-MDH和ADH同工酶具有特殊的表达谱式:m-MDH和ADH均由两个基因座位编码;肾脏在LDH-A_3B与LDH-A_2B_3之间多出1条LDH酶带(LDH-X)。本文还讨论了草鱼同工酶的遗传基础和亚基组成,以及本实验的某些结果与其他作者的结果不

草鱼同工酶发育遗传学研究——Ⅱ.早期发育过程中的同工酶分析

采用淀粉凝胶电泳技术研究了草鱼早期发育过程中(受精后0—200小时)6种同工酶系统(LDH、MDH、GDH、ADH、IDH、EST)的表达谱式。除了ADH以外,其余5种同工酶系统均具有明显的发育变化谱式。根据早期发育过程中同工酶的变化谱式及其组织分布,草鱼的同工酶可分为三大类型:(1)在未受精卵及早期发育过程中一直存在,并常有较广泛的组织分布;(2)未受精卵及早期发育过程中均不存在,一般仅分布于少数几种组织中;(3)未受精卵及胚胎发育早期不存在,直到早期发育过程中某一特定时期才开始出现。

鲮鱼冷休克及其死亡的某些生化因素

采用分光光度法和淀粉凝胶电泳法初步研究了鲮鱼冷休克前后脑乙酰胆碱酯酶(AchE)活力和三种酶的同工酶类的动态变化。并根据鲮鱼在冷休克期间(7—6℃)脑AchE活力显著降低和肝脏组织乳酸脱氢酶(LDH)同工酶活性明显升高以及苹果酸脱氢酶(MDH)、酯酶(EST)同工酶类出现酶活性变化的情况,讨论了导致鲮鱼耐寒能力差的某些生化因素。同时提出脑AchE可以作为评定鲮鱼冷休克期间中枢神经系统受害程度的一种生化指标。

几种罗非鱼乳酸脱氢酶和苹果酸脱氢酶同工酶的电泳研究

用淀粉凝胶垂直平板电泳比较分析了三种口孵类型罗非鱼的6种组织的乳酸脱氢酶(LDH)和苹果酸脱氢酶(MDH)同工酶谱及其相对迁移特性,发现这两种同工酶在各个种内表现出组织的分布特异性,而在各个种间又具有明显的差异。利用LDH同工酶的F基因和MDH同工酶的A、B、C、D基因作为遗传标志,能够将亲缘关系相近的这三种罗非鱼区别开来,从而为形态分类学提供了新的生化证据,并且对于以育种为目的的亲本选择,具有一定的实用意义。

异源精子在银鲫雌核发育子代中的生物学效应

黑龙江省方正县双凤水库的两性型银鲫群体是三倍体雌核发育种群。异源精子不仅能刺激银鲫卵雌核发育,而且还能影响雌核发育子代的某些性状,如对于子代的生长、性比、体色和肝脏LDH同工酶等都产生了影响。为区别于原有术语“雌核发育gynogenesis”,我们把这种表现了异源精子生物学效应的雌核发育称之为“异精雌核发育allogynogenesis”,发育的子代称之为“异育银鲫”。异育银鲫已以其明显的生长优势在生产上显示了优良的经济性状。

20种鲤科鱼类同工酶的表型分析及有关进化问题的探讨

本文对20种鲤科鱼类的同工酶表型进行了分析比较。鲌亚科中存在几种不同的LDH同工酶表型,以各种LDH同工酶表型所组成的一些类群,反映出亚科水平中属间的亲缘关系。按同工酶的表型可将它们分为4个类群,这些类群的划分和进化趋异的过程是与经典的系统分类相一致的。按LDH同工酶表型的异同可将鲌亚科、密鲴亚科和鲢亚科的鱼类划分成两个主要的支系。一支鱼类是具有相同迁移率的LDH-A-4 同工酶,其中包括鲌亚科的多数鱼类,由LDH 同工酶的表型推断它们与雅罗鱼亚科有较密切的亲缘关系;另一支鱼类则是具有相同迁移率的 LDH

几种鲤科鱼类及杂种的乳酸脱氢酶同工酶的比较

用聚丙烯酰胺凝胶电泳法,分析了14种鲤科鱼类和4个杂交种的肌肉、心脏、晶状体、脑和肾脏的乳酸脱氢酶(LDH)同工酶。根据LDH酶谱的异同可将雅罗鱼亚科的5种鱼分成两组:草鱼、鳡和鳤;青鱼和赤眼鳟。鳊亚科中青梢红鲌的LDH谱形与长春鳊、团头鲂和红鳍鲌相似,而与(歺又鱼)条有明显的区别。鲢亚科中的鳙与鲢的谱形相似。密鲴亚科中的细鳞斜颌鲴与黄尾密鲴的谱形也非常相似。将谱形相似的鱼类进行杂交,如细鳞斜颌鲴♀×黄尾密鲴♂、鳙♀×鲢♂,不仅杂种的成活率高而且可繁殖后代。谱形相差很大的鱼类进行杂交,如草鱼♀×团头鲂♂及

青、草、鲢、鳙的乳酸脱氢酶同功酶谱及其与毒物作用的关系

本文报道了我国四大家鱼——青、草、鲢、鳙的乳酸脱氢酶(LDH)同功酶电泳图谱及毒物对草鱼血清乳酸脱氢酶(SLDH)同功酶谱的影响。 用聚丙烯酰胺垂直平板电泳,可以测出鲢、鳙血清中各有一条深色的LDH带、背、草鱼血清中含有五条深色的LDH同功酶带。草鱼不同器官组织匀浆中的LDH同功酶相对活性比例不同,与人类相似。 0.1ppm氯化汞、氯化镉、硝酸铅、硫酸铜,0.008ppm滴滴涕和0.84ppm对硫磷分别使草鱼致毒33天,发现氯化镉、硝酸铅使SLDH_5活性升高,氯化汞使SLDH_1升高,而硫酸铜使SLDH

Plasma biochemical responses of the planktivorous filter-feeding silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) to prolonged toxic cyanobacterial blooms in natural waters

The planktivorous filter-feeding silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) are the attractive candidates for bio-control of plankton communities to eliminate odorous populations of cyanobacteria. However, few studies focused on the health of such fishes in natural water body with vigorous toxic blooms. Blood parameters are useful and sensitive for diagnosis of diseases and monitoring of the physiological status of fish exposed to toxicants. To evaluate the impact of toxic cyanobacterial blooms on the planktivorous fish, 12 serum chemistry variables were investigated in silver carp and bighead carp for 9 months, in a large net cage in Meiliang Bay, a hypereutrophic region of Lake Taihu. The results confirmed adverse effects of cyanobacterial blooms on two phytoplanktivorous fish, which mainly characterized with potential toxicogenomic effects and metabolism disorders in liver, and kidney dysfunction. In addition, cholestasis was intensively implied by distinct elevation of all four related biomarkers (ALP, GGT, DBIL, TBIL) in bighead carp. The combination of LDH, AST activities and DBIL, URIC contents for silver carp, and the combination of ALT. ALP activities and TBIL, DBIL. URIC concentrations for bighead carps were found to most strongly indicate toxic effects from cyanobacterial blooms in such fishes by a multivariate discriminant analysis. (C) 2009 Elsevier B.V. All rights reserved.

Plasma biochemical responses of the omnivorous crucian carp (Carassius auratus) to crude cyanobacterial extracts

Healthy crucian carp (Carassius auratus) were treated by intraperitoneal (i.p.) injection of crude cyanobacterial extracts at two doses, 50 and 200 mu g MC-LR equiv kg(-1) BW. High mortality (100%) was observed within 60 h post injection in the high-dose group. In the treated fish, activities of four plasma enzymes, alanine aminotransferase (ALT), alkaline phosphatase (ALP), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH), all showed substantial increases, with both dose and time-dependent effects. These increases of enzyme activity indicate severe impairment occurred in the liver of crucian carp over time. Plasma concentrations of energy-related biomolecules including glucose (GLU), cholesterol (CHO), triglyceride (TG), and total protein (TP) showed marked changes in the high-dose group, possibly a nutritional imbalance correlated with the liver injury caused by intraperitoneal exposure to crude cyanobacterial extracts.

Cytotoxicity evaluation of three pairs of hexabromocyclododecane (HBCD) enantiomers on Hep G2 cell

Hexabromocyclododecanes (HBCDs) are additive brominated flame retardants mainly used in plastics and textiles. At the present time, these compounds are found in almost all environmental and human samples. In order to evaluate the environmental safety and health risk of HBCDs, the enantiomerically pure alpha-, beta-, and gamma-HBCD were prepared using high performance liquid chromatography (HPLC) on a PM-P-CD column and the cytotoxicities of their enantiomers were evaluated in Hep G2 cells. Results from the 3-(4,5-dimethylthioazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), resazurin reduction and lactate dehydrogenase (LDH) release assays showed a good agreement that the order of cytotoxicity was gamma-HBCD >= beta-HBCD > alpha-HBCD, and that significantly lower cell viability and higher LDH release were observed in all (+)-enantiomers ((+) alpha-, (+) beta- and (+) gamma-HBCD) than the corresponding (-)-forms ((-) alpha-, (-) beta- and (-) gamma-HBCD). Additionally, the formation of reactive oxygen species (ROS) induced by these HBCD enantiomers were detected. The positive correlation between the LDH release and ROS formation demonstrated that the toxic mechanism might be mediated by oxidative damage. These results suggest that environmental and human health risks of HBCDs must be evaluated at the level of individual enantiomers. (C) 2008 Published by Elsevier Ltd.

Apoptosis induction on human hepatoma cells Hep G2 of decabrominated diphenyl ether (PBDE-209)

Polybrominated diphenyl ethers (PBDEs) are an important class of halogenated organic brominated flame retardants. Because of their presence in abiotic and biotic environments widely and their structural similarity to polychlorinated biphenyls (PCBs), concern has been raised on their possible adverse health effects to humans. This study was designed to determine the anti-proliferative, apoptotic properties of decabrominated diphenyl ether (PBDE-209), using a human hepatoma Hep G2 line as a model system. Hep G2 cells were cultured in the presence of PBDE-209 at various concentrations (1.0-100.0 mu mol/L) for 72 h and the percentage of cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The results showed that PBDE-209 inhibited the cells viability in time and concentration-dependent characteristics at concentrations (10.0-100.0 mu mol/L). We found that anti-proliferative effect of PBDE-209 was associated with apoptosis on Hep G2 cells by determinations of morphological changes, cell cycle and apoptosis. Mechanism study showed that PBDE-209 could increase the generation of intracellular reactive oxygen species (ROS) concentration-dependently. Antioxidant N-acetylcyteine partially inhibited the increase of ROS. The mechanism for its hepatoma-inhibitory effects was the induction of cellular apoptosis through ROS generation. In addition, activity of lactate dehydrogenase (LDH) release increased when the cells incubated with PBDE-209 at various concentrations and times. These results suggested that PBDE-209 had the toxicity activity of anti-proliferation and induction of apoptosis in tumor cells in vitro. (c) 2007 Elsevier Ireland Ltd. All rights reserved.

Sequential ultrastructural and biochemical changes induced in vivo by the hepatotoxic microcystins in liver of the phytoplanktivorous silver carp Hypophthalmichthys molitrix

Up to now, in vivo studies on the toxic effects of microcystins (MCs) on the ultrastructures of fish liver have been very limited. The phytoplanktivorous silver carp was injected i.p. with extracted hepatotoxic microcystins (mainly MC-RR and -LR) at a dose of 1000 mu g MC-LReq. kg(-1) body weight, showing a time-dependent ultrastructural change in liver as well as significant increases in enzyme activity of plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH). We observed for the first time the occurrence of a large amount of activated secondary lysosomes, which might be an adaptive mechanism to eliminate or lessen cell damage caused by MCs through lysosome activation. Quantitative and qualitative determinations of MCs in the liver were conducted by HPLC and LC-MS2, respectively. MCs concentration in the liver reached the maximum (114.20 mu g g(-1) dry weight) after 3 h post-injection, and then rapidly dropped to 7.57 mu g g(-1) dry weight at 48 h, indicating a deputation of 99% accumulated MC-LReq. On the other hand, a decrease trend in glutathione (GSH) concentration was observed in the liver of silver carp while the activity of glutathione S-transferase (GST) increased significantly after injection. The high tolerance of silver carp to MCs might be due to the high basic GSH level in their liver, and/or an increased GSH synthesis. (C) 2007 Elsevier Inc. All rights reserved.

First report of aphantoxins in China - waterblooms of toxigenic Aphanizomenon flos-aquae in Lake Dianchi

The oligohaline cyanobacterium Aphanizomenon flos-aquae (L.) Ralfs (A. flos-aquae) has been reported in several countries to produce paralytic shellfish poisons (PSPs) or protracted toxic effects. In the past years, A. flos-aquae blooms have occurred annually in the eutrophic Lake Dianchi (300 km(2) in area, located in southwestern China). Material from natural blooms dominated by A. flosaquae was collected and lyophilized. Acute toxicity testing was performed by mouse bioassay using extracts from the lyophilized material. Clear symptoms of PSPs, intoxications were observed. To confirm the production of PSPs, a strain of A. flos-aquae (DC-1) was isolated and maintained in culture. Histopathological effects were studied by examining the organ damages using transmission electron microscopy (TEM). Slight hepatocytic damage with swollen mitochondria was found. The ultrastructural pulmonary lesions were characterized by distortied nuclei and indenting of karyotheca, together with degeneration and tumefaction of mitochondria and endoplasmic reticulum. Control animals injected with acetic acid did not exhibit histopathological damage in any organ. Toxic effects of cultured algal cells on enzymatic systems in the mouse were studied using sublethal doses of extracts. Significant glutathione-S-transferase (GST) and lactate dehydrogenase (LDH) increases, together with decrease of the glutathione (GSH) level, were measured. These results indicated a potential role of PSPs intoxicating and metabolizing in the test animals. HPLC-FLD and LC/MS analysis of extracts from cultured material demonstrated the PSP toxins produced by A. flos-aquae bloom. To the best of our knowledge, this is the first study reporting chemically and toxicologically confirmed PSP toxins related to A. flosaquae in China. (c) 2005 Elsevier Inc. All rights reserved.

EROD activities in a primary cell culture of grass carp (Ctenopharyngodon idellus) hepatocytes exposed to polychlorinated aromatic hydrocarbonas

Aryl hydrocarbon (Ah) receptor (Ah-agonist) effects of environmental samples containing polychlorinated aromatic hydrocarbons were evaluated using a 7-ethoxyresorufin-O-deethylase (FROD) assay of a primary hepatocyte culture from grass carp (Ctenopharyngodon idellus). The results were compared with those obtained from the assay using the rat hepatoma cell line H4IIE and chemical analysis using high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). A dose-response relationship was observed between the EROD activities, either from primary hepatocyte culture assay or from H4IIE assay, and concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The results showed that the assay based on the H4IIE cell line (EC50 = 0.83 mug/mL) is more sensitive to TCDD than the assay based on primary hepatocyte Culture (EC50 = 9.7 pg/mL). In tests of environmental samples, the results from the assay using primary hepatocyte culture were comparable to those from the assay using the H4IIE cell line and chemical analysis of concentrations of mixtures of polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/PCDF). The lack of a change in the activities of glutathione-S-transferase (GST) and lactate dehydrogenase (LDH) in cell culture upon exposure to TCDD indirectly indicates that the compound is persistent to biodegradation in the cell culture system. (C) 2004 Elsevier Inc. All rights reserved.