可口革囊星虫不同组织同工酶的比较

采用聚丙烯酰胺凝胶电泳(PAGE)技术,研究了可口革囊星虫5种组织(收吻肌、吻、肠、肾管及体壁)10种同工酶(ADH、GCDH、SDH、EST、LDH、ME、POD、SOD、MDH、CAT)的表达。结果表明:除CAT外,其余9种同工酶均得到了较为清晰的酶谱,除SOD和MDH在5种组织中表型相同外,其它7种同工酶的表达均具有明显的组织特异性。SDH-2、EST-1、LDH-1和POD-1为收吻肌所特有;ADH-3、ADH-4、GCDH-2、GCDH-4、GCDH-5、EST-10和LDH-6均为吻所特有;EST-4为肾管所特有。在肠中,ADH和GCDH均没有检测到活性。初步探讨了5种组织中各种同工酶的分布与活性及其与各组织生理功能的关系。     

连翘叶提取物对力竭及恢复小鼠脑组织抗氧化酶活性和LDH同工酶的影响

为研究连翘叶提取物(FSE)对力竭及恢复小鼠脑组织SOD、POD、MDA和LDH同工酶的影响,用分光光度法测定小鼠脑组织MDA含量及SOD和POD活性,用聚丙烯酰胺凝胶电泳分析LDH同工酶。结果表明,FSE可以提高力竭状态下小鼠脑组织SOD和POD活性,降低力竭及恢复状态下小鼠脑组织MDA的含量;FSE还可以降低力竭状态下脑组织LDH活性,提高恢复状态下小鼠脑组织LDH4-5的活性;FSE对对力竭运动状态下的脑组织有保护作用,对延缓运动中枢疲劳有积极的作用。     

细鳞斜颌鲴不同组织中LDH同工酶的比较研究

采用垂直板聚丙烯酰胺凝胶电泳技术和特异性染色方法分析了细鳞斜颌鲴脑、肾脏、肝脏、肌肉、心脏和眼6种组织的LDH同工酶,结果表明酶谱的表达具有明显的组织特异性.酶带共由三个基因座位(Ldh-a、-b、-c)编码,在6种组织中共检测到7条带,其中脑、肾脏、心脏和眼四种组织中均发现3条带,肝脏中7条带,肌肉中1条带且为超显性,在PAGE胶趋向阴极侧检测到4条肝脏组织所特有的Ldh-c基因编码带;各组织中酶带活性顺序为脑LDH-1>LDH-2>LDH-3,肾脏LDH-3>LDH-l>LDH-2,肝LDH-3>LDH-5>LDH-2>LDH-6>LDH-1>LDH-4>LDH-7,心脏LDH-1>LDH-2>LDH-3,眼LDH-3>LDH-1>LDH-2,肌肉仅有LDH-3;由迁移率Rf(LDH-A4)A;对酶谱进行扫描分析及亚基计算得到了一致的结果:脑和心脏两种组织中Ldh-b基因表达占优势而肾脏、肝脏、眼和肌肉中Ldh-a基因表达占优势.     

东方铃蟾不同发育阶段乳酸脱氢酶同工酶的变化

东方铃蟾乳酸脱氢酶(LDH)同工酶的表达在不同发育阶段以及不同的组织有其特异性。心脏中以LDH-1占优势,骨骼肌和肝脏中以LDH-5占优势,脑中LDH-1与LDH-5的相对含量接近。从鳃盖期至成体,心、肝、骨骼肌的LDH同工酶谱型不发生转换。心脏的LDH同工酶含量无阶段间的差异;肝、骨骼肌的LDH同工酶相对含量变化发生在从尾退化期至成体这一时期。在尾退化期,脑中LDH同工酶谱型发生转换,但LDH同工酶相对含量变化的幅度较小。     

华南兔组织乳酸脱氢酶同工酶的研究

本文以聚丙烯酰胺凝胶电泳法分析华南兔(Lepus sinensis sinensis)11种组织乳酸脱氢酶同工酶的分布待征。分析结果:骨骼肌和肝组织5条同工酶带俱全;脑、肺、卵巢和盲肠等组织各含有4条谱带(LDH-1,-2,-3和-4);胃和肾组织含有3条谱带(LDH-1,-2,和-3);眼晶状体和睾丸组织也含有3条谱带,但前者是LDH-3,-4和-5,后者是LDH-1,-2和-5;谱带最少的是心肌组织,只有2条(LDH-1和-2)。此外,还对各组织中的亚基活性分布及电泳图谱特征进行了分析。     

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。     

吉富罗非鱼不同组织中4种同工酶研究

采用聚丙烯酰胺凝胶电泳分析了吉富罗非鱼肌肉、肠、肝、胰、胃不同组织中酯酶(EST)、乳酸脱氢酶(LDH)、超氧化物歧化酶(SOD)、蛋白酶同工酶组成。结果表明:吉富罗非鱼的这4种同工酶均有明显的组织特异性。EST在肌肉组织中表达量较低,EST-1在肠中表达较高,胰、肝组织中均由6种EST同工酶谱带组成;LDH-5在肌肉组织中含量较高;SOD在肝、肌肉组织中表达较高;肠、肝蛋白酶活性较高,由5种同工酶谱带组成,胰蛋白酶含有一种同工酶。该研究为杂交鱼类的酶工程、生化遗传研究提供理论基础,进一步促进吉富罗非鱼这一优良养殖品种的开发和利用。     

臭鼩血清蛋白和六种组织乳酸脱氢酶同工酶的研究

本实验对臭鼩的血清蛋白及心肌、骨骼肌、肾脏、脾脏、肝脏,睾丸6种组织器官的乳酸脱氢酶(LDH)同工酶进行了聚丙烯酰胺凝胶盘状电泳的分析研究。臭鼩血清蛋白存在15—17条带,各组织的LDH同工酶均由5条带构成,其中心肌LDH-1、LDH-2和肾脏LDH-1各出现1条亚带。     

镉对平菇菌丝生长及同工酶表达的影响

采用液体培养研究了不同浓度镉（Cd）处理7d对平菇（Pleurotus ostreotus）菌丝体生长及其同工酶表达的影响.结果表明,50 μmol/L Cd处理对平菇菌丝生长抑制率为55.6%,2000μmol/L Cd为菌丝生长致死浓度.同工酶活性电泳图谱显示,Cd处理不仅改变酯酶（EST）、乳酸脱氢酶（LDH）、过氧化物酶（POD）和超氧化物岐化酶（SOD）同工酶带数,而且也影响各酶带的表达强度.50 μmol/L和100μmol/L Cd处理分别诱导出2条和3条新的POD同工酶带,而抑制一条分子量较大的POD酶带的表达,但明显增强总的POD活性.正常生长的平菇菌丝体LDH同工酶谱只出现2条酶带,50 μmol/L以下Cd处理不影响其同工酶的表达,100 μmol/L Cd处理组2条同工酶带均消失.50和100μmol/L Cd处理能够显著增强SOD活性,且诱导2条SOD同工酶表达.100μmol/L及其以下浓度Cd处理均能提高EST的活性,这可能具有加速细胞内酯类化合物水解而增加羧基的数量以螯合更多的游离Cd离子而解Cd毒的作用.Cd浓度在50μmol/L以下时,随着处理浓度的增加,对金属硫蛋白的诱导作用呈逐渐增强的趋势,而100 μmol/L Cd的诱导作用减弱.     

He-Ne激光处理不同时期蚕豆幼苗对抗氧化系统的影响

采用功率为3.50 mW/mm2的He-Ne激光处理不同时期蚕豆,研究其四叶期叶片中丙二醛(MDA)含量,超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性及同工酶谱的变化。结果表明,与对照相比,He-Ne激光处理不同时期蚕豆,MDA含量均显著降低,且各处理间没有显著差异;SOD、POD、CAT酶活性有不同程度提高。SOD、POD同工酶的酶谱在浸种24小时和胚芽露头期经激光处理后改变,在一叶期处理后没有改变;CAT同工酶谱没有变化;在一叶期处理的三种同工酶谱都没有改变。     

岳鲤及其双亲(荷包红鲤♀、湘江野鲤♂)LDH同工酶的研究

用聚丙烯酰胺凝胶电泳,结合CS910双波长扫描分析了岳鲤及其双亲(荷包红鲤♀、湘江野鲤♂)6种组织的乳酸脱氢酶同工酶(Lactate Dehydrogenase,LDH)。结果表明:岳鲤及其双亲的LDH同工酶均存在组织特异性;亲本之间LDH同工酶的差异主要表现在肝脏;亲本各组织的大多数LDH同工酶在F_1代得到表现;亲本及F_1代的LDH同工酶可能由基因位点AA′BB′共同控制。本文还讨论了LDH同工酶分析和杂交结果预测的关系。     

Carbohydrate energy metabolism in Fasciola gigantica (trematoda)

Umezurike G. M. and Anya A. O. 1980. Carbohydrate energy metabolism in Fasciola gigantica (Trematoda). International Journal for Parasitology10: 175–180. Adult Fasciola gigantica contained 4.49 ± 0.06 % (mean ± S.D.) wet weight glycogen. Tissue homogenates contained high levels of malate dehydrogenase (MDH), NAD-linked malic enzyme (ME), Phosphoenolpyruvate carboxykinase (PEPCK) and lactate dehydrogenase (LDH). MDH, PEPCK and ME activities appeared to be localized in both cytosolic and mitoehondrial fractions, fumarase activity appeared to be predominantly mitochondrial whereas LDH and pyruvate kinase activities were cytosolic in distribution. Polyacrylamide gel electrophoresis revealed the predominance of LDH-1, LDH-2 and LDH-3 but only traces of LDH-4 and LDH-5 isoenzymes in the crude cytosolic fraction. LDH activity in the crude sample was inhibited by excess substrate (pyruvate). The mitoehondrial system showed NADH -cytochrome c oxidoreductase, succinate-cytochrome c oxidoreductase, NADH oxidase and some cytochrome c-oxygen oxidoreductase activities. Under anaerobic conditions, NADH-fumarate oxidoreductase and succinate-NAD + oxidoreductase activities of mitoehondrial preparations were stimulated in the presence of ADP and ATP respectively. Isolated mitochondria contained rhodoquinone and no ubiquinone, and isolated rhodoquinone was readily reduced by succinate in the presence of submitochondrial particles. Hydrogen peroxide was produced by submitochondrial particles in the presence or absence of KCN or in the presence of fumarate.     

Selective inactivation of lactate dehydrogenase of rat tissues by sodium deoxycholate.

Soluble lactate dehydrogenase (EC 1.1.1.27) extracted from brain, skeletal and cardiac muscle and liver of rats, and purified isoenzymes LDH-1 and LDH-5, were incubated with sodium deoxycholate. Deoxycholate almost totally inactivated isoenzyme LDH-5 (A4), whereas it left isoenzyme LDH-1 (B4) unaffected. Tissue lactate dehydrogenase was inactivated to different degrees depending on the origin of the enzyme. Electrophoretic isoenzyme studies of tissue lactate dehydrogenase showed the loss of activity to be quantitatively related to the overall percentage of subunit A distributed among the homotetramer LDH-5 and the heterotetramers LDH-2, LDH-3 and LDH-4. It was concluded that subunit A of lactate dehydrogenase interacts selectively with deoxycholate, irrespective of its association with subunit B. Distinct changes in electrophoretic mobilities of deoxycholate-treated isoenzymes strongly indicated an indiscriminate binding of deoxycholate by all LDH isoenzymes, probably through hydrophobic interactions. The results suggest that the inactivation of the enzyme is non-competitive, but the basis of the selectivity of deoxycholate towards subunit A is not known at present.     

Additional lactate dehydrogenase (LDH) isoenzymes in normal testis and spermatozoa of adult man

Summary Adult human testicular tissue contains up to six previously undescribed lactate dehydrogenase (LDH) isoenzymes in addition to the five LDH isoenzymes normally found and the sixth found in spermatogenic cells and spermatozoa, LDH-X. Additional LDH isoenzymes were also found in spermatozoa but not in seminal fluid or in serum. After electrophoresis one additional LDH isoenzyme of testicular tissue was localized between LDH-1 and LDH-2, two between LDH-2 and LDH-3, two between LDH-3 and LDH-4, and two between LDH-4 and LDH-5. These localizations indicate that the additional LDH isoenzymes are tetramers combining the A and B subunits of the five normal LDH isoenzymes and the C subunit of LDH-X. The additional LDH isoenzymes may be important in the metabolism of spermatogenic germ cells and spermatozoa.     

UV-induced changes of structural and functional properties of blood lactate dehydrogenase isoenzymes in free state and in the presence of serotonin

Photoinduced changes of structural and functional properties of lactatedehydrogenase isoenzymes from human erythrocytes in free state and in the presence of serotonin have been studied by means of gel chromatography, electrophoresis, IR-spectrophotometry and by the method of definition of catalytic activity. UV-light influence induces photoinactivation of erythrocyte's LDH, while its inhibitory effect intensifies with the increase of irradiation dose. The complicated character of changes in electrophoretic mobility and percentage content of isoenzymes LDH-1, LDH-2, LDH-3 under the influence of UV-rays testifies that the decrease of total enzyme activity of these isoforms in connected with their different photosensitiveness and represents the result of many-staged process which is characterized both by the consistent and parallel proceeding of its individual photochemical reactions. A pronounced photoprotective effect of serotonin towards the molecules of erythrocytic LDH isoenzymes has been discovered. It seems to be caused by formation of enzyme--biogenous amine complex affecting the secondary protein structure.     

朱砂叶螨危害对豇豆幼苗叶片活性氧代谢相关酶的影响

朱砂叶螨危害豇豆幼苗后,叶绿体内与活性氧代谢有关的酶SOD、ASP活性及同工酶均受到不同程度的影响。(1)受害2～8d,SOD活性与对照相比均升高,差异显著。不同虫口密度之间在4d时SOD活性差异显著;(2)在危害期内,随着危害时间的延长ASP活性显著升高,且不同虫口密度之间差异极显著,虫口密度越大,ASP活性越高;(3)SOD同工酶谱带显示,随着危害程度的加强,一些分子量较大的同工酶谱带亦加强。     

L.D.H. and L.D.H. isoenzymes of the intra-uterine secretions of the cow during the estrous cycle

Uterine secretions were collected from 20 mature cows during estrus (day 0), metestrus (day 5), diestrus (day 10) and proestrus (day-1). Lactate dehydrogenase (LDH) and LDH isoenzymes activity were evaluated. No significant cyclic variations of LDH activity was found in the uterine secretions while the mean of the enzyme activity was higher during the estrogenic period of the cycle. The relative activity of LDH-1, LDH-2 and LDH-3 isoenzymes were higher during proestrus and estrus whereas LDH-5 activity was more important during metestrus. The LDH-3 seems to have the higher relative activity in uterine secretions of the cow.     

Glycolytic enzymes in polyamine-treated bovine retina

The retina is characterized by glycolysis under aerobic conditions, mediated by lactate dehydrogenase isoenzyme-5 (LDH-5) as well as by the soluble isoenzyme of malate dehydrogenase. Bovine retina LDH and MDH isoenzymes and their activities were studied after polyamine treatment. Our results showed that LDH-5 isoenzyme presented the highest activity in untreated as well as in putrescine-treated retina. Decreased activity was present when the retina was treated with spermidine or spermine. It was demonstrated that retinic LDH-5 had a high affinity for lactate which enabled the isoenzyme to be more effective than the other LDH isoenzymes in the conversion of NADH to NAD. Therefore, the putrescine enhancing LDH-5 activity appeared to be capable of stimulating NAD-mediated rhodopsin regeneration. Putrescine induced a marked increase of both MDH isoenzymes--soluble (s-MDH) and mitochondrial (m-MDH), while spermine and spermidine mostly affected the soluble form of the enzyme. Putrescine induced a three-fold increase in s-MDH and m-MDH activities, while spermine and spermidine induced a four to five-fold increase in s-MDH. These results document the differential effects of polyamine treatment on LDH and MDH isoenzyme activities.     

Changes in the lactate dehydrogenase isoenzyme spectrum during T-lymphocyte differentiation

The pattern of lactate dehydrogenase isoenzyme spectrum changes on different stages of T-lymphocyte differentiation was studied An enriched population of stem cells has LDH-5, 4 and 3 isoenzymes, and much less LDH-2 activity. The isoenzyme pattern of thymic cell precursors consists of LDH-5, 4, 3 and 2. All the five LDH isoenzymes were found in cortical thymocytes. Medullary thymocytes reveal LDH-5, 4 and 3 isoenzymes. T-lymphocytes of peripheral lymphoid organs contain mainly LDH-5 and in a lesser degree LDH-4 activity.     

Trypanosoma cruzi: Lactate dehydrogenase isoenzymes and infections in mice

Total plasma LDH isoenzyme (EC 1.1.1.27) levels increased significantly over the normal level in mice infected with strains of Trypanosoma cruzi from three different geographic locations, but some strain differences were observed. The most rapid increase was exhibited by the blood-induced Tulahuen strain, but this strain, unlike the House 510 or House 11, did not elicit an increase during the early period of infection. Overall increases in LDH-1 and LDH-2, heart isoenzymes, were most marked in vector-derived House 510 infections, but, as in the Tulahuen strain, a considerable increase was also observed in blood-induced infections. The House 510 strain also elicited significant increases in LDH-4; these were particularly high during the early period of the blood-induced infection. By contrast, the vector-derived Tulahuen strain elicited a higher increase in LDH-4 during the early period than the House 510 or House 11 strains. Comparable similarites and differences were also observed in regard to LDH-3, 5, and “X.” The most marked isoenzyme increases were those of “LDH-X” exhibited by the blood-induced House 510 and vector-derived Tulahuen strains.Parallel histopathologic studies of liver, heart, and skeletal muscle disclosed significant pathology in all the infections. Animals with blood-induced Tulahuen strain infections characteristically showed extensive necrosis with marked multiplication of parasites throughout the liver, but little or no evident damage to the heart and skeleal muscle. Animals infected with House 510 and House 11 strains exhibited minimal pathology in the liver but severe damage to the heart and skeletal muscle. Increases in LDH-4 and LDH-5, isoenzymes which represent both liver and skeletal muscle, in blood-induced Tulahuen infections were attributed largely to liver damage, but in the House 510 and House 11 infections were related more to skeletal muscle.