小鼠组织中过氧化氢酶的活性与年龄的关系

为观察小鼠组织中过氧化氢酶的活性与年龄的关系,采用高锰酸钾滴定法测定不同年龄(1、4、18月龄)小鼠肝、肾、肺、心、脾、胃、脑组织中过氧化氢酶的活性。结果显示:小鼠过氧化氢酶在不同组织中活性不同,活性高低顺序基本表现为:肝>肾>肺>心、脾、胃>脑;小鼠肺、心、脾、胃、脑各组织中过氧化氢酶的活性在1～4月龄间随年龄增加而增加,在4～18月龄间随年龄增加而降低;小鼠肝、肾组织中过氧化氢酶的活性在1～4月龄间与年龄相关性不显著,在4～18月龄间随年龄增加而降低。结果表明,小鼠肝、肾、肺、心、脾、胃、脑等组织中过氧化氢酶的活性随年龄变化而变化,机体过氧化氢酶活性的降低与机体衰老密切相关。     

镉暴露诱导黄颡鱼鳃的组织学损伤、氧化应激和免疫反应

为研究水体镉(Cd)暴露对黄颡鱼(Pelteobagrus fulvidraco)鳃的组织学结构、抗氧化状态及免疫相关基因表达的影响, 将黄颡鱼分别暴露于0(对照组)、50和200 μg/L Cd水体中8周后, 取鳃进行分析。结果显示: 鳃中Cd含量随着水体Cd浓度的升高而上升; 组织学分析发现, Cd暴露组鳃出现了动脉瘤、细胞增生、鳃小片弯曲以及细胞脱落等病理变化。同时, Cd暴露导致鳃中谷胱甘肽-S-转移酶(GST)、谷胱甘肽过氧化物酶(GPx)和抗羟自由基(AHR)的活性及过氧化氢(H₂O₂)的含量升高, 而过氧化氢酶(CAT)的活性及还原型谷胱甘肽(GSH)的含量下降, 但超氧化物歧化酶(SOD)的活性无显著变化。此外, Cd暴露上调了肿瘤坏死因子-α(tnf-α)、主要组织相容性复合体(mhc)、白细胞介素-10(il-10)、转化生长因子-β(tgf-β)和补体因子C3(c3)的表达, 而下调了白细胞介素-1β(il-1β)、白细胞介素-8(il-8)及溶菌酶(lys)的转录水平。研究表明, Cd暴露导致黄颡鱼鳃中Cd富集, 进而诱导鳃的组织学损伤、氧化应激和免疫反应。     

养殖半滑舌鳎肝胰、中肾、鳃、头肾、脾和心中酸性磷酸酶、碱性磷酸酶和过氧化物酶的组织化学定位

目的研究半滑舌鳎肝胰、中肾、鳃、头肾、脾和心中酸性磷酸酶(ACP)、碱性磷酸酶(ALP)和过氧化物酶(POX)的分布及组织定位。方法取健康半滑舌鳎肝胰、中肾、鳃、头肾、脾和心组织进行固定,冰冻切片后进行酶组织化学染色和光密度定量统计分析。结果 ACP活性部位为棕色,主要分布于肝胰小叶间胆管和静脉,中肾肾小体中的肾小球和肾间质的肾小管,头肾和脾中的巨噬细胞以及心肌层中,在鳃中未见有分布;ALP活性部位被染为蓝紫色,主要分布于肝胰的胰腺腺泡内,中肾肾间质的肾小管,鳃的鳃丝血管和上皮细胞,脾静脉的管壁处和椭圆体,心外膜和肌膜上以及头肾的血窦腔内皮;POX活性部位被染为茶褐色,主要分布于肝胰小静脉和肝血窦内的血细胞,中肾肾间质的血细胞,鳃的鳃丝血管、鳃小片血窦和上皮细胞,头肾、脾内的血细胞以及心的心肌层和血细胞中。ACP活性由大到小依次为心、肝胰、脾、中肾、头肾;ALP活性由大到小依次为中肾、鳃、头肾、脾、心、肝胰;POX活性由大到小依次为脾、头肾、肝胰、中肾、鳃、心。结论 ACP、ALP和POX在半滑舌鳎6种组织中分布特点不同,其活性大小在不同组织中有显著差异。     

低温驯化锯缘青蟹鳃抗氧化防护、ATPase及膜脂肪酸组成变化

锯缘青蟹(Scylla serrata)低温环境下生理生化的变化对于理解其低温适应具有重要的意义。本研究中采用生物化学的方法对低温驯化下锯缘青蟹鳃中超氧化物歧化酶(Superoxide dismutase,SOD)、过氧化氢酶(Catalase,CAT)、谷胱甘肽过氧化物酶(Glutathione peroxidase,GPX)的活性,脂质过氧化产物丙二醛(malondialdehyde,MDA)含量,4种ATPase(Na ,K -ATPase,Mg2 -ATPase,Ca2 -ATPase和Ca2 ,Mg2 -ATPase)活性及细胞膜脂肪酸组成进行测定。实验结果显示青蟹鳃中抗氧化酶(SOD、CAT和GPX)活性在3个驯化温度下,随驯化温度的降低而升高。SOD活性在5℃和10℃驯化下显著高于对照组(27℃组)(p<0.01);CAT活性在3个驯化温度下均显著高于对照组(p<0.01或p<0.05);GPX活性仅5℃驯化下显著高于对照组(p<0.01)。MDA含量低温驯化下升高,但仅5℃驯化下显著高于对照组(p<0.01)。鳃中4种ATPase活性均是随驯化温度的降低而升高,并且5℃和10℃驯化下均显著高于对照组(p<0.01或p<0.05)。低温驯化下C18:0、C18:1、C18:2、C18:3、C20:5和C22:6等脂肪酸与对照组相比均发生显著性变化(p<0.01或p<0.05),饱和指数∑SFA/∑UFA显著下降(p<0.01或p<0.05)。低温驯化下锯缘青蟹鳃中抗氧酶及ATPase活性升高,说明其具有明显的温度补偿效应,它是对低温适应的一种积极反应。鳃中MDA低温驯化下积累是活性氧自由基未能被及时清除而产生氧化应激的结果。低温下细胞膜脂肪酸饱和指数降低是维持细胞膜执行正常生理功能的需要。     

小白鼠心、肝、骨骼肌组织中琥珀酸脱氢酶活性的研究

通过对小白鼠采取断头、脱颈椎、打扑不同的处死方法,研究心、肝、骨骼肌不同组织中琥珀酸脱氢酶(SDH)活性的大小.结果发现,3种不同的处死方法中,心、肝、骨骼肌SDH的活性大小依次为心＞肝＞肌;在三者的混合组织中SDH的活性大小依次为打扑＞断头＞脱颈椎处死法.因而得出结论,不同的处死方法对心、肝、骨骼肌组织中SDH的活性大小没有明显影响;在混合组织中以打扑处死法SDH的活性最强.     

苯并[a]芘暴露对三疣梭子蟹鳃、肝胰腺组织毒理学指标的影响1

本文研究了三疣梭子蟹(Portunus trituberculatus)在对苯并[a]芘(Ba P)富集(15 d)、释放(15 d)过程中其鳃和肝胰腺组织的4种毒理学指标的响应。4种毒理学指标分别为7-乙氧基异吩噁唑酮-脱乙基酶(EROD)、谷胱甘肽硫转移酶(GST)、超氧化物歧化酶(SOD)和脂质过氧化(LPO)。设置了0.05μg/L和0.45μg/L两个实验组以及海水和丙酮对照组。结果显示,在富集阶段,与海水对照组相比,第1天时0.05μg/L和0.45μg/L实验组鳃、肝胰腺组织的各毒理指标均显著受到诱导(P0.05),诱导程度随Ba P暴露浓度的增加而增大。而后鳃、肝胰腺组织的EROD、GST活性以及鳃组织的SOD活性达到峰值后下降,肝胰腺组织的SOD活性以及鳃、肝胰腺组织的丙二醛(MDA)含量则持续增加。鳃组织的EROD、GST、SOD活性到达峰值时间早于肝胰腺组织,其活性以及MDA含量也低于肝胰腺组织。在释放阶段,0.45μg/L实验组鳃组织的SOD活性,0.05μg/L和0.45μg/L两个实验组肝胰腺组织的SOD活性均依然显著高于同期海水对照组水平(P0.05),其余各浓度实验组鳃、肝胰腺组织均能恢复到同期海水对照组水平(P0.05)。实验结果表明,三疣梭子蟹的鳃组织对于Ba P暴露响应时间比肝胰腺组织更早,但均具有一定的恢复能力。     

低盐胁迫对三疣梭子蟹组织中抗氧化酶和 AT P 酶活力的影响

设定半致死低盐试验组(盐度 7)和正常对照组(盐度 28)对三疣梭子蟹进行 48h 的胁迫, 检测半致死盐度胁迫下不同时间点三疣梭子蟹组织中抗氧化酶和 ATP 酶活力的变化。结果显示, 随着低盐处理时间的延长, 三疣梭子蟹肝胰腺、鳃、肌肉中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活力均呈下降趋势, 极显著低于对照组(P<0.01), 各组织中 SOD、 CAT 活力大小顺序为肌肉 >肝胰腺>鳃; 肝胰腺、鳃中谷胱甘肽过氧化物酶(GPX)、谷胱甘肽转硫酶(GST)、谷胱甘肽还原酶(GR)、Na+/K+-ATPase 酶和 Ca2+/Mg2+-ATPase 酶活力也都被抑制, 活力极显著下降(P<0.01); 而对照组在试验期间各组织酶活均较 平稳, 变化不大。试验结论表明 , 当盐度下降剧烈, 超出机体耐受范围时, 三疣梭子蟹生理机能被抑制, 酶活力反而下降。     

镧对鲤鱼肾和鳃抗氧化性和酯酶同工酶的影响

在实验条件下采用静水换水法,研究了不同浓度(0.01、0.1、2.0和5.0mg·L-1)的LaCl3对鲤鱼肾和鳃抗氧化性和酯酶(EST)同工酶的影响.结果表明:在LaCl3,实验浓度范围内,处理4个月后,鳃中超氧化物歧化酶(SOD)活性受到显著抑制,肾中SOD活性、鳃中过氧化脂质(120)含量及0.01、O.1、5.0mg·L-1组肾中LPO含量与相应对照组相比均无显著性差异(P＞0.05),2.0 mg·L-1组肾中LPO含量却显著高于对照;0.01、0.1mg·L-1组,肾和鳃中过氧化物酶(POD)活性值均显著高于相应对照组(P＜0.05或P＜0.01),5mg·L-1组,肾和鳃POD活性均受到显著抑制;同工酶电泳实验结果表明:La3 能导致鲤鱼肾和鳃SOD、EST谱带亮度发生明显变化,鳃和肾EST同工酶原有的一些酶带消失,肾EST同工酶出现一些新的谱带,这种影响因La3 浓度不同而异.     

苯并[a]芘暴露对三疣梭子蟹鳃、肝胰腺组织毒理学指标的影响

本文研究了三疣梭子蟹(Portunus trituberculatus)在对苯并[a]芘(BaP)富集(15 d)、释放(15d)过程中其鳃和肝胰腺组织的4种毒理学指标的响应.4种毒理学指标分别为7-乙氧基异吩噁唑酮-脱乙基酶(EROD)、谷胱甘肽硫转移酶(GST)、超氧化物歧化酶(SOD)和脂质过氧化(LPO).设置了0.05 μg/L和0.45 μg/L两个实验组以及海水和丙酮对照组.结果显示,在富集阶段,与海水对照组相比,第1天时0.05 μg/L和0.45μg/L实验组鳃、肝胰腺组织的各毒理指标均显著受到诱导(P＜0.05),诱导程度随BaP暴露浓度的增加而增大.而后鳃、肝胰腺组织的EROD、GST活性以及鳃组织的SOD活性达到峰值后下降,肝胰腺组织的SOD活性以及鳃、肝胰腺组织的丙二醛(MDA)含量则持续增加.鳃组织的EROD、GST、SOD活性到达峰值时间早于肝胰腺组织,其活性以及MDA含量也低于肝胰腺组织.在释放阶段,0.45pg/L实验组鳃组织的SOD活性,0.05μ-g/L和0.45 μg/L两个实验组肝胰腺组织的SOD活性均依然显著高于同期海水对照组水平(P＜0.05),其余各浓度实验组鳃、肝胰腺组织均能恢复到同期海水对照组水平(P＞ 0.05).实验结果表明,三疣梭子蟹的鳃组织对于BaP暴露响应时间比肝胰腺组织更早,但均具有一定的恢复能力.     

肠呼吸抑制胁迫对大鳞副泥鳅呼吸代谢和抗氧化能力的影响

为研究肠呼吸抑制胁迫对气呼吸鱼类大鳞副泥鳅(Paramisgurnus dabryanus)的鳃和肠道呼吸代谢及抗氧化能力的影响,初步探究其生理反馈调节机制,本文选取大鳞副泥鳅成熟个体(n=60)进行肠呼吸抑制胁迫实验。分别对实验组(肠呼吸抑制,n=30)与空白对照组(n=30)的大鳞副泥鳅饲养驯化2周,测定其整体静止代谢率、呼吸频率、鳃和肠道各段的乳酸脱氢酶(LDH)、琥珀酸脱氢酶(SDH)、Na+/K+ATP酶(NKA)、过氧化氢酶(CAT)以及超氧化物歧化酶(SOD)活性。肠呼吸抑制胁迫下,实验组与对照组大鳞副泥鳅整体静止代谢率无显著差异(P0.05),而实验组大鳞副泥鳅鳃部呼吸频率显著加快(P0.05)。与对照组相比,实验组大鳞副泥鳅鳃部的琥珀酸脱氢酶活性显著升高(P0.05),而后肠琥珀酸脱氢酶和Na+/K+ATP酶显著降低(P0.05)。同时实验组大鳞副泥鳅后肠的乳酸脱氢酶活性显著升高(P0.05)。实验组和对照组之间,大鳞副泥鳅鳃和前中肠的过氧化氢酶以及超氧化物歧化酶酶活性无显著差异(P0.05),后肠则有显著性升高(P0.05)。当大鳞副泥鳅肠呼吸受到抑制时,会加强其鳃部有氧呼吸代谢,弥补肠呼吸缺失部分,满足机体生理需求,而气呼吸的后肠会有一定氧化应激反应。     

社鼠组织器官同工酶的研究

用聚丙烯酰胺凝胶等电聚焦电泳方法,分析了社鼠的肝、肾、心肌、骨骼肌、肺、脾和脑等多种组织器官的ＬＤＨ、ＡＤＨ、ＥＳＴ、和ＳＯＤ４种同工酶,对各组织器官的酶带数目和分布,以及酶活性进行了比较研究。结果表明,社鼠的ＬＤＨ同工酶、ＡＤＨ同工酶和ＥＳＴ同工酶具有比较明显的组织特异性,而ＳＯＤ同工酶的组织特异性较低。肺和脾除ＥＳＴ同工酶活性较高外,脑除ＬＤＨ同工酶活性较高外,其它３种同工酶的活性均较低;而肝和肾中４种同工酶的活性普遍很高。心肌和骨骼肌因氧张力不同而使ＬＤＨ同工酶酶谱存在明显差异,但其它３种同工酶酶谱却非常相似。同工酶的组织特异性与各组织器官所执行的生理功能是相一致的     

青草鲢鳙四种鱼同工酶的比较研究

采用聚丙烯酰氨垂直板状连续电泳方法,对青草鲢鳙６种组织、１０种同工酶和蛋白质进行了电泳研究,并结合作者以前做的工作,对所研究的共２１种同工酶和蛋白质在４种鱼中的组织分布,位点表达及活性作了分析和总结。结果表明：４种鱼同工酶的种内组织分布差异大于种间差异;ＡＤＨ、ＡＭＹ、ＣＡＴ、ＥＳＴ、ＭＥ、ＰＯＸ、ＳＤＨ存在不同程度的种间差异,可作为种类的遗传标记;４种鱼ＭＤＨ、ＧＯＴ、ＡＬＰ、ＡＯ、ＳＯＤ同工酶谱非常相似,只在活性上略有差异;ＬＤＨ、Ｇ６ＰＤＨ和ＣＯＸ的酶谱特征可作为青草和鲢鳙两个亚科的鉴别标记。     

镉对蟾蜍的4种器官乳酸脱氢酶同工酶的影响

以腹腔注射法对蟾蜍(Bufo bufo gargarizans)给镉,处理一周后,观察了4种镉中毒浓度(0．1、0．2、0．4、0．8mg／kg)条件下的蟾蜍心、肝、肾和睾丸中乳酸脱氢酶(LDH)同工酶的变化。结果表明：随着镉中毒浓度的升高,心脏LDH同工酶的活性明显升高,睾丸LDH同工酶的活性明显下降,肝中的LDH1、LDH2、LDH3、LDH5在0．4、0．8mg／kg浓度组酶活性明显增加,而LDH4则明显减弱,肾中LDH1的活性随镉浓度的升高而明显升高,其它各酶带活性出现先增强而后又逐渐减弱的现象。结果提示了镉对蟾蜍主要器官LDH同工酶的影响具有组织差异性。     

Electrophoretic analyses of alcohol dehydrogenase, aldehyde dehydrogenase, aldehyde oxidase, sorbitol dehydrogenase and xanthine oxidase from mouse tissues.

1. Cellulose acetate zymograms of alcohol dehydrogenase (ADH), aldehyde dehydrogenase, sorbitol dehydrogenase, aldehyde oxidase, "phenazine" oxidase and xanthine oxidase extracted from tissues of inbred mice were examined. 2. ADH isozymes were differentially distributed in mouse tissues: A2--liver, kidney, adrenals and intestine; B2--all tissues examined; C2--stomach, adrenals, epididymis, ovary, uterus, lung. 3. Two NAD+-specific aldehyde dehydrogenase isozymes were observed in liver and kidney and differentially distributed in other tissues. Alcohol dehydrogenase, aldehyde oxidase, "phenazine" oxidase and xanthine oxidase were also stained when aldehyde dehydrogenase was being examined. 4. Two aldehyde oxidase isozymes exhibited highest activities in liver. 5. "Phenazine oxidase" was widely distributed in mouse tissues whereas xanthine oxidase exhibited highest activity in intestine and liver extracts. 6. Genetic variants for ADH-C2 established its identity with a second form of sorbitol dehydrogenase observed in stomach and other tissues. The major sorbitol dehydrogenase was found in high activity in liver, kidney, pancreas and male reproductive tissues.     

中国大鲵乳酸脱氨酶同工酶研究I组织分布

采用垂直板聚丙烯酰胺凝胶电泳和紫外分光光度法分析大鲵１５种组织的乳酸脱氢酶（ＬＤＨ）同工酶后发现：在正常生理条件下,大鲵体内只有Ｈ４和Ｍ４两种同工酶,红细胞只有Ｍ４一种同工酶;大鲵体内ＬＤＨ同工酶中,以Ｍ４占绝对优势;除生殖腺及脑外,在幼体至成体的发育过程中,ＬＤＨ同工酶未见变化;大鲵体内各组织ＬＤＨ含量及前述两种同工酶相对含量不同。     

Purification of the Type II and Type III isozymes of rat hexokinase, expressed in yeast.

C-terminally His-tagged versions of the Type II and Type III isozymes of rat hexokinase were expressed in Pichia pastoris and Schizosaccharomyces pombe, respectively. Milligram amounts of the homogeneous isozymes were readily obtained in good yield by chromatography on Ni-NTA columns. The specific activities were 133 +/- 4 and 76 +/- 3 u/mg for the purified Type II and Type III isozymes, respectively. The K(m)'s for glucose and ATP were in good agreement with values in the literature for the isozymes isolated from mammalian tissues. The Type III isozyme exhibited substrate inhibition at elevated levels of glucose, as previously observed for this isozyme isolated from mammalian tissue sources.     

Changing patterns of placental hexokinase isozymes during the course of gestation.

Hexokinase, an enzyme that is capable of regulating the entry of glucose into metabolic sequences, is known to exist in four isozyme forms in a variety of mammalian tissues. Each of these isozymes possesses different kinetic properties, suggesting that they may serve in different regulatory capacities. In addition, the proportions of the four isozymes are characteristically different for various differentiated tissues, presumably reflecting different metabolic capabilities of the tissues.Extracts of rabbit and human placentas from early gestational age and term pregnancies were chromatographed and assayed for hexokinase activity. Four peaks of activity were observed. Elution positions of the four placental hexokinase isozymes were comparable to those from liver; however, the relative proportions were considerably different. In both rabbit and human placentas, the proportion of Type I hexokinase increased during gestation and Type III decreased, while Types II and IV remained essentially unchanged. Implications of the gestational changes for placental carbohydrate metabolism are discussed.     

A Comparison of Two Sucrose Synthetase Isozymes from Normal and shrunken-1 Maize

The maize sucrose synthetase isozyme (SS2) present in sh1 endosperm, sh1 seedlings, and in suspension culture cells was purified to homogeneity from each of these tissues by sequential ammonium sulfate fractionation, diethylaminoethyl-cellulose chromatography, gel filtration chromatography, and affinity elution with UTP from a carboxymethyl-cellulose column. Cyanogen bromide digests were used to demonstrate that the SS2 isozymes in these different tissues are structurally identical and are therefore the product of the same gene. The sucrose synthetase produced by the Sh1 gene (SS1) was purified by modification of the SS2 procedure and was used in comparative analyses of the two isozymes. Ouchterlony assays demonstrated that SS1 and SS2 have partial antigenic identity. The two isozymes have similar enzyme kinetics in the sucrose cleavage reaction but differ in their relative activities with ADP and TDP. The amino acid compositions of SS1 and SS2 are similar, and proteolytic digests revealed that they share limited structural homologies.     

Organ selective induction of cytochrome P-448 isozymes in the rat by 2-methoxy-4-aminoazobenzene and 3-methylcholanthrene

Male Sprague Dawley rats were injected intraperitoneally with 2-methoxy-4-amino-azobenzene (2-MeO-AAB) or 3-methylcholanthrene (MC), and then the expression of microsomal cytochrome P-450 isozymes in liver and extrahepatic tissues was investigated by means of immunological methods and a bacterial mutation test. The results of protein A-enzyme-linked immunosorbent assaying and immunoblotting using anti-rat cytochrome P-448 monoclonal antibodies showed that MC induced at least two microsomal cytochrome P-448 isozymes, a high spin form (cytochrome P-448H) and a low spin form (cytochrome P-448L), in liver, but that it induced only cytochrome P-448L in extrahepatic tissues such as lung, kidney, small intestine, and colon. The results also indicated that, in contrast to MC, 2-MeO-AAB selectively induced microsomal cytochrome P-448H in liver but did not induce any cytochrome P-448 isozymes in extrahepatic tissues. The activities of 9,000 X g supernatants from the individual organs, as to the mutagenic conversion of 3 aromatic amines (3-amino-1-methyl-5H-pyrido(4,3-b)indole, 2-amino-6-methyldipyrido(1,2-a: 3',2'-d)-imidazole and 3-methoxy-4-aminoazobenzene), toward Salmonella typhimurium TA 98 bacteria were dependent upon the quantity and/or quality of the microsomal cytochrome P-448 isozymes in the organs.     

Effects of exogenous auxins on expression of lipoxygenases in cultured soybean embryos

The expression of lipoxygenases (LOXs) is known to be developmentally regulated in soybeans (Glycine max. [L.] Merr.). Hormones have been firmly established as being involved in the growth and developmental processes of a number of plant species. Correlation between the expression of LOXs and the development and germination of soybean embryos suggests that plant hormones may affect the expression of LOXs. The present studies were conducted to investigate the effects of exogenous auxins on the expression of LOX isozymes and LOX activities in cultured cotyledon tissues of immature soybean seeds. The results revealed that at least one of the more acidic nonembryo LOX isozymes was induced by either α-naphthaleneacetic acid or indoleacetic acid but not by 2,4-dichlorophenoxyacetic acid after 4 days' exposure. Levels of LOX-1, -2, and -3 proteins and activities were significantly decreased by 2,4-dichlorophenoxyacetic acid 10 days after explanting. S1 analysis showed that embryo LOX messenger RNAs were detectable in the tissues treated with each of the auxins. The reduced levels of the embryo LOX proteins may, therefore, be regulated at the levels of translation, posttranslational modification, or degradation. The more acidic isozymes induced by α-naphthaleneacetic acid showed enzymatic activity and shared the same molecular mass and isoelectric point values as the germination-associated LOX isozymes found in hypocotyls and radicles, suggesting that those LOXs are involved in germination competency of soybean embryos.