高压快速柱分离纯化牛血球超氧化物歧化酶的研究

以牛血球为材料,经溶血等处理和丙酮沉淀,获得牛血球超氧化物歧化酶粗品。此粗酶可以通过ＤＥＡＥ－Ｓｅｐｈａｒｏｓｅ和ＣＭ－Ｓｅｐｈａｒｏｓｅ快速柱层析,获得超氧化物歧化酶纯品。纯化的酶比活可达１３５００ｕ／ｍｇ,经ＰＡＧＥ、ＳＤＳ－ＰＡＧＥ和快速蛋白液相色谱（ＦＰＬＣ）检测,结果表明,纯化酶是均一的Ｓｅｐｈａｄｅｘ Ｇ－１００凝胶过滤测得该酶分子量为３１,８００,ＳＤＳ－ＰＡＧＥ测得亚基分子量为１５     

TNT在大鼠晶状体内的代谢及其对晶状体中抗氧化相关酶活性的影响

大鼠皮下注射ＴＮＴ,以ＨＰＬＣ分析其在晶状体内的代谢过程,并检测晶状体谷胱甘肽过氧化物酶、谷胱甘肽还原酶及超氧化物歧化酶的活性变化。发现在注射ＴＮＴ后２ｈ即可在晶状体内检测到为量极少的ＴＮＴ及其代谢产物,第１２ｈ一氨基二硝基甲苯含量达最高峰。鼠龄较小的大鼠晶状体内ＴＮＴ及其代谢产物高于鼠龄较大的大鼠．多剂量注射ＴＮＴ时大鼠晶状体内一氨基二硝基甲苯于第２天达到高峰,ＴＮＴ于第５天达饱和状态,第１８天一氨基二硝基甲苯含量与ＴＮＴ含量相近。谷胱甘肽过氧化物酶、谷胱甘肽还原酶及超氧化物歧化酶活性在注射ＴＮＴ的第２天均有不同程度的升高,在第５天和第１８天维持在低活性状态。实验表明ＴＮＴ在晶状体内是通过硝基还原而代谢的．ＴＮＴ进入晶状体后初期可诱发晶状体抗氧化相关酶活性的增高,后期则导致晶状体抗氧化相关酶活性的降低。     

浒苔多糖的降血脂及其对SOD活力和LPO含量的影响

浒苔多糖剂量１５０ｍｇ／ｋｇ可使高胆固醇血症小鼠血清胆固醇下降２２％,剂量１６８ｍｇ／ｋｇ可使高脂血症大鼠ＴＣＨ和ＴＧ分别降低５８％和６１％,ＨＤＬ升高２７％,剂量２５０ｍｇ／ｋｇ可分别提高血清、脑和肝ＳＯＤ活力３３％、１１８％和２２４％,剂量１６８ｍｇ／ｋｇ对高血脂大鼠血清和心脏ＬＰＯ含量降低３５％和４６％。     

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     

干旱胁迫下小麦叶片微粒体活性氧自由基的产生及其对膜的伤害

从不同干旱胁迫时间下的小麦(Triticum aestivum L.)叶片中提取微粒体膜,测定活性氧自由基变化和膜伤害程度。结果表明,随着干旱胁迫时间的延长发生以下变化:(1)O_2~-和H_2O_2的产生速率在一定时间内逐渐加快然后下降;(2)膜脂过氧化产物丙二醛(MDA)的含量逐渐增加;(3)微粒体膜上的SOD活性逐渐下降;(4)—SH基的含量在一定时间内逐渐增多以后下降;(5)与膜伤害程度有关的生理指标如根系电导率、叶片水势及其含水量等均有变化。     

Free Radical Enhancer Xenobiotic is an Inducer of Cataract in Rabbit

Free radical enhancers, diquat, paraquat, plumbagin and juglone were used to study the oxy radical-induced damage to the rabbit lens in vitro and in vivo. Each compound caused a 6–8 fold increase in malondialdehyde (MDA) and a 30–55% decrease in reduced glutathione of the lens in vim. These peroxidative and oxidative changes were potentiated in the presence of 100% 0., abolished by N, and prevented by desferal-Mn (III) (DF-Mn) or liposomal superoxide dismutase (LSOD) indicating the involvement of O₂^?.

Diquat injected intravitreally as a single dose (300nmole in 30μl of isotonic saline) in the right eye of a 5-wk-old Dutch belted rabbit, induced early cataract after 24–72h. The lens of the contralateral control eye injected with isotonic saline had no change. In the right eye, O₂,^? and OH -productions were significantly (P < 0.01) higher; O₂-, was about 16 fold higher in the aqueous humor and vitreous humor, and 5 fold in the lens and retina, and OH. was 35 fold higher in the aqueous humor, 2 fold in vitreous humor and 5 fold in the lens and retina as compared to the respective tissues of the control eye. Enhanced lipid peroxidation in the lens was apparent from the higher levels of MDA and formation of aminophospholipid-MDA Schiff-base conjugates.

We propose that cyclic oxidation-reduction of xenobiotics coupled to the endogenous redox systems in the eye, could generate oxy radicals in excessive amounts, triggering cataractogcnesis.     

Synthesis,characterization and biological aspects of novel five-coordinated dimeric-Cu(II) systems

The structural and spectroscopic properties of novel five-coordinated dimeric-Cu(II) system have been investigated. The biocidal activities of all eight compounds, ligands, cupric nitrate and standard drugs against six bacteria and three fungi were determined. The DNA interaction activity of complexes was studied using spectrophotometry and electrophoresis. The superoxide dismutase (SOD)-like activity of the complexes was compared with previously reported monomeric- and dimeric copper complexes. The results support the five-coordinated dimeric square pyramidal geometry for the quinolone-Cu(II) system.     

Effect of MCI-186 on Postischemic Reperfusion Injury in Isolated Rat Heart

MCI-186 (3-methyl-1-phenyl-2-pyrazolin-5-one) is a newly developed antioxidant which has been shown to reduce brain edema in cerebral ischemia through inhibition of the lipoxygenase pathway of arachidonic acid. However, its effect on myocardial reperfusion injury after prolonged ischemia has not yet been demonstrated. We compared the mode of the effect of MCI-186 and recombinant human CuZn superoxide dismutase (rh-SOD) in isolated perfused rat hearts subjected to 60-min ischemia followed by 60-min reperfusion. Left ventricular developed pressure (LVDP), necrotic area and the release of creatine phosphokinase (CPK) and endogenous CuZn superoxide dismutase (endoge-SOD) were measured to evaluate myocardial damage. The decrease in left coronary flow (CBF) was measured as an index of the damage of left coronary circulation. MCI-186 (17.5 mg/L) was perfused for 10 min in the MCI group and rh-SOD (70 mg/L) was perfused during the reperfusion period in the SOD group starting 5 min prior to reperfusion. The release patterns of CPK and endoge-SOD were analyzed to elucidate the difference in the mode of protection of MCI-186 and rh-SOD. The LVDP remained higher in both MCI and SOD groups than that of control (76 ± 1, 77 ± 2 and 69 ± 1% of preischemic value, respectively). The necrotic area was significantly attenuated in both MCI and SOD groups compared with that in the control group (16 ± 1,14 ± 1 and 32 ± 170, respectively, p<0.05). Total CPK release was lower in both MCI and SOD groups thfn in the control (78 ± 7, 100 ± 2 and 116 ± 4 × 10³ units/g myocardium respectively). The decrease in CPK release was more marked in the MCI group than that in the SOD group (p<0.05). The reduction in CBF was significantly attenuated by the treatment with rh-SOD or MCI-186, but the effect was much higher in the SOD group than in the MCI group (69 ± 5, 58 ± 2, and 48 ± 2% in SOD, MCI and control groups, respectively). The release pattern of endoge-SOD was identical to that of CPK and thus this did not distinguish the mode of effect of MCI-186 from that of rh-SOD. These results indicate that MCI-186 reduces reperfusion injury in isolated perfused hearts with prolonged ischemia and the effect is more closely related to the reduction of myocyte damage than the preservation of the coronary circulation.     

Differential Expression of Antioxidant Enzymes During Degradation of Azo Dye Reactive black 8 in Hairy roots of Physalis minima L.

The enzymes involved in the protection of plant metabolism in presence of azo dye was characterized by studying activities of the role of antioxidant enzymes in the hairy roots (HRs) of Physalis minima L. during degradation of an azo dye, Reactive Black 8 (RB8). When the HRs were exposed to RB8 (30 mg L^?1), a nine fold increase in SOD activity was observed after 24 h, while 22 and 50 fold increase in activity was observed for POX and APX respectively after 72 h, whereas there was no significant change in activity of CAT. The activation of different antioxidant enzymes at different time intervals under dye stress suggests the synchronized functioning of antioxidant machinery to protect the HRs from oxidative damage. FTIR analysis confirmed the degradation of dye and the non-toxic nature of metabolites formed after dye degradation was confirmed by phytotoxicity study.     

不同花生品种对旱涝胁迫的响应及生理机制

为评价花生对旱、涝胁迫的响应,本试验以4个旱、涝耐性差异明显的花生品种为材料,运用温室防雨盆栽方法,在苗期、花针期分别进行正常灌溉(对照)、干旱(7d,叶片萎蔫)、根部淹涝(土面水深2 cm,时间1d、3d、7d)和整株淹涝(水深至苗顶,时间1d、3d、7d)的处理,测定地上部及根系生物量、根冠比、根系活力、叶片超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量。结果表明,苗期、花针期干旱均抑制地上部生长,提高根冠比;苗期干旱降低根系生物量,而花针期增加。2个时期淹涝均促进地上部生长、抑制根系生长、降低根冠比,并随淹水加深、延时而加重。旱、涝条件下根系活力均降低,SOD、MDA呈上升趋势。遭受相同时间(7d)的水分胁迫后,危害程度以干旱重于淹涝,花针期重于苗期。基于生物量、生理指标变化的综合分析进一步表明,4个花生品种的旱、涝耐性差异很大,湘花55号耐旱性强、耐涝性弱,豫花15号耐旱性弱、耐涝性强,中花4号耐旱、涝性均最弱,中花8号耐旱、涝性均最强。