兔晶体机械性损伤致白内障机理的研究

采用兔晶体机械性损伤造成外伤性白内障模型，对丙二醛（ＭＤＡ）、超氧化物歧化酶（ＳＯＤ）、谷胱甘肽过氧化酶（ＧＳＨｐＸ）指标进行动态观察，发现兔的白内障晶体ＭＤＡ含量显著升高，而ＳＯＤ及ＧＳＨ－ｐｘ活性均显著下降（ｐ＜０．０１）。结果表明：晶体内脂质过氧化作用明显增强，而抗氧化能力显著下降。提示：晶体损伤后自由基大量增加并参与白内障的病理过程，这一研究结果进一步支持了致白内障的自由基学说，为外伤性白内障的防治提供实验依据。     

Brain palmitate incorporation in awake and anesthetized rats

Uniformly labeled [14C]palmitate was injected intravenously in awake and barbiturate-anesthetized rats, and arterial plasma radioactivity due to unesterified [14C]palmitate was determined on plasma samples removed at timed intervals up to the time of death. Overall brain radioactivity was determined by liquid scintillation spectroscopy, and regional brain radioactivity was determined by quantitative autoradiography. The transfer constant, k, for the unidirectional uptake of radiotracer palmitate into the brain at 4 h was calculated from the brain radioactivity and the integrated plasma radioactivity from injection to 4 h. The unidirectional palmitate uptake was calculated as the product of k and the plasma concentration of unesterified palmitate. Barbiturate anesthesia reduced regional palmitate transfer constants and unidirectional palmitate uptakes into different brain regions by 40-60%. Palmitate incorporation into the brains of awake rats at 4 h represents uptake into structural brain components which contain lipids. The results indicate that pentobarbital anesthesia reduces this rate of incorporation by about half.     

远洋船员血浆超氧化物歧化酶活力和丙二醛含量的检测

①目的观察中国远洋船员血浆超氧化物歧化酶（ＳＯＤ）和丙二醛（ＭＤＡ）含量的改变。②方法采用分光光度比色法检测５３例远洋船员血浆ＳＯＤ活力和ＭＤＡ含量变化。③结果中国远洋船员血浆ＳＯＤ活力比陆地工作人群明显降低（ｔ＝７．９３，Ｐ＜０．００１）；而血浆ＭＤＡ含量则显著增高（ｔ＝３．５１，Ｐ＜０．００１）；连续海上航行大于１８０ｄ者的血浆ＳＯＤ活力明显低于连续海上航行小于１８０ｄ者（ｔ＝７．９１，Ｐ＜０．００１），而血浆ＭＤＡ含量比连续航行小于１８０ｄ者明显升高（ｔ＝２．４１，Ｐ＜０．０５）。④结论中国远洋船员机体抗氧化能力降低     

莜麦粉对不同年龄大鼠的抗氧化作用

莜麦粉对不同年龄大鼠的抗氧化作用ＥｆｅｃｔｓｏｆＮａｋｅｄＯａｔｓＦｌｏｕｒｏｎＡｎｔｉｏｘｉｄａｔｉｏｎｉｎＲａｔｓｗｉｔｈＤｉｆｅｒｅｎｔＡｇｅｓ王明正王峰峰１谭秀桃１魏惠如（山西医科大学药理教研室，太原０３０００１）ＷａｎｇＭｉｎｇｚｈｅｎｇ...     

93例儿童血脂谱水平与ApoB基因多态性关系的研究

目的观察儿童血脂谱水平与载脂蛋白Ｂ（ＡｐｏＢ）基因变异的关系。方法对９３名８～１１岁汉族儿童进行了ＡｐｏＢ基因ＸｂａⅠ位点多态性基因型频率及基因型与血脂谱水平关系的研究。结果此人群中ＸｂａⅠ位点优势等位基因Ｘ－频率为０．９６７，少见等位基因Ｘ＋频率为０．０３３；Ｘ－Ｘ＋基因型者（此人群中无Ｘ＋Ｘ＋者）血浆总胆固醇、低密度脂蛋白－胆固醇（ＬＤＬ－ｃｈ）水平均值（４．５９和２．９８ｍｍｏｌ／Ｌ）显著高于Ｘ－Ｘ－基因型者（３．８４和２．３２ｍｍｏｌ／Ｌ），全部６例Ｘ－Ｘ＋者中的４例，其总胆固醇和／或ＬＤＬ－ｃｈ测定值分别超过了Ｐ９０，显示了Ｘ＋等位基因与高血浆胆固醇水平的联系。结论ＡｐｏＢ基因ＸｂａⅠ位点多态性与儿童血脂谱水平有一定程度的关联，有可能是儿童血脂谱水平异常的遗传标志之一。     

3种保健食品对大鼠血清脂质过氧化和抗氧化酶的影响

目的：研究3种保健食品对大鼠血清脂质过氧化和抗氧化酶的影响。方法：将SD（sprague-dawley)老年大鼠随机分为4组（一个对照组，3个试验组），试验组喂饲受试物30d，采尾血测脂质过氧化产物丙二醛（mdlon-adehyde,MDA)和超氧化物歧化酶（superoxide dismtse,SOD)。结果美因子羊胎素与宁夏枸杞王胶囊的中浓度组和高浓度组，保龄西洋参的低浓度组和中浓度组大鼠血清中MDA含量低于对照组（P＜0．05，P＜0．01）。美因子羊胎素的3个试验组、宁夏枸札王胶囊中浓度组和高浓度组，保龄西洋参的低浓度组大鼠血清中SOD活性高于对照组（P＜0．05）。结论：3种保健食品具有不同程度抗脂质过氧化作用。     

Hydroxyl radical production and lipid peroxidation paralles selective post-ischemic vulnerability in gerbil brain

The salicylate trapping method was used to investigate the changes in hydroxyl radical (·OH) levels in the selectively vulnerable hippocampus compared to the cerebral cortex of gerbils subjected to a 10 min period of near complete forebrain ischemia. Salicylate-derived 2,5-dihydroxybenzoic acid (2,5-DHBA) was measured in sham-operated animals and at 1, 5, and 15 min of reperfusion. A basal level of 2,5-DHBA was also seen in non-ischemic gerbil brain, both in the hippocampus and cortex. The hippocampal basal level was 160% higher than in the cortex (P < .01). Treatment with the cytochrome P450 inhibitor SKF-525A (50 mg/kg s.c. 30 min before measurement) did not affect this basal level in either hippocampus or cortex, which argues against a contribution of metabolic salicylate hydroxylation as its source. In contrast, pretreatment with the arachidonic acid cyclo-oxygenase inhibitor ibuprofen (20 mg/kg s.c.) decreased (?68.8%) the level of salicylate hydroxylation in the hippocampus, but not the cortex. In animals subjected to 10 min of forebrain ischemia, a selective increase in 2,5-DHBA was observed in the hippocampus at 1 min of reprerfusion which subsided by 5 min. No increase in salicylate hydroxylation was apparent in the cortex within the same time frame. The increase in ·OH in the hippocampus at 1 min of reperfusion was accompanied by a significant decrease (?15%; P < .03) in the hippocampal levels of vitamin E. No loss of vitamin E was observed in the cortex at the same time. It is hypothesized that the selective ischemic vulnerability of the hippocampus is mechanistically related to a selective post-ischemic burst in ·OH in that region. Moreover, this may be based upon an intrinsically higher level of oxidative stress in that region as a by-product of greater arachidonic acid turnover. © 1993 Wiley-Liss, Inc.     

Characterization of the antioxidant effects of melatonin and related indoleamines in vitro

Abstract: The antioxidant and possible pro-oxidant effects of melatonin and related indoleamines (tryptophan, serotonin, N-acetylserotonin, and 5-methoxytryptamine) were studied in vitro. In two model membrane systems, i.e., phospholipid liposomes and rat erythrocytes, lipid peroxidation induced by Fe²⁺ and H₂O₂, respectively, were reduced by the tested indoleamines except for tryptophan. The 5-hydroxy-indoleamines, serotonin, and N-acetylserotonin exhibited pro-oxidant actions in the bleomycin assay by reducing Fe³⁺ to Fe²⁺, which leads to DNA damage. The 5-methoxy-indoleamines, melatonin and 5-methoxytryptamine, were devoid of any pro-oxidant actions in this assay. Serotonin, but not N-acetylserotonin, scavenged the superoxide anion. None of the indoleamines tested had any reactivity towards H₂O₂. All the indoleamines, including tryptophan, were, however, shown to react with hypochlorous acid. These findings support an antiperoxidative and antioxidant action of melatonin which is devoid of pro-oxidant effect on non-lipid substrates.     

大豆皂甙对胰岛素下的平滑肌细胞脂质过氧化反应的影响

目的 :观察大豆皂甙对高浓度胰岛素下兔血管平滑肌细胞脂质过氧化反应的影响。方法 :采用兔主动脉平滑肌细胞培养 ,细胞随机分为正常对照组、胰岛素组及不同浓度大豆皂甙组 ,加药后继续培养 72 h,计数后测定细胞内过氧化脂质 (LPO)及超氧化物歧化酶 (SOD)含量。结果 :单纯高浓度胰岛素升高细胞内 LPO水平 ,降低细胞内 SOD活力 ,大豆皂甙与胰岛素共同孵育后 ,升高SOD活力 ;大豆皂甙低于 2 0 mg/L时抑制 LPO的产生 ,高于或等于 50 mg/L时促进 LPO的合成。结论 :高浓度胰岛素通过升高平滑肌细胞内 LPO促进动脉粥样硬化的形成 ,一定浓度的大豆皂甙抑制胰岛素所致脂质过氧化反应 ,对动脉粥样硬化具有防治作用