乙醇及乙醛对胚胎发育的联合作用

为探讨乙醇及其代谢产物乙醛在胎儿酒精综合征 (FAS)中的作用 ,应用植入后全胚胎培养研究不同浓度的乙醇 ,乙醛组合对 9.5- 1 1 .5d大鼠胚胎发育的联合作用 .结果显示在卵黄囊直径 ,头长 ,体长 ,心脏 ,前脑 ,DNA含量等指标乙醇与乙醛存在交互作用 .进一步分析发现 0 .1 g·L-1乙醇与不同剂量乙醛组合可导致拮抗 ,协同和独立等多种联合作用类型 ,但对头长和脑均表现为独立作用 . 0 .2 g· L-1乙醇与不同剂量乙醛组合除心脏呈协同作用外其余均为乙醇独立作用 .上述结果提示 FAS中的脑发育异常是乙醇独立作用的结果 ,乙醛则引起FAS中的辅助畸形     

硫酸铝在体外对大鼠胚胎组织谷胱甘肽含量和卵黄囊细胞膜流动性的影响

目的　为探讨铝的发育毒性及机理。方法孕 9.5d大鼠胚胎于体外培养系统中给予不同剂量的硫酸铝 ,培养 4 8h后 ,观察胚胎生长发育和器官形态分化状况 ;应用二硫代双硝基苯甲酸 (DTNB)直接法测定胚胎组织谷胱甘肽 (GSH)含量 ;以 1,6 二苯己三烯为荧光探剂 ,用荧光偏振技术测定卵黄囊细胞膜脂质流动性。结果　当培养液中铝浓度为1.2mg·L- 1时 ,胚胎生长发育和分化明显被抑制 ;3.0mg·L- 1时 ,畸形胚胎发生率明显升高 ,主要有神经管闭合不全 ,脑发育不良和体翻转不全 ;6 .0mg·L- 1时 ,胚胎组织GSH含量和卵黄囊细胞膜脂质流动性显著降低。上述效应均呈现出一定的剂量 效应 (反应 )关系。结论　铝有潜在的致畸性和胚胎毒性 ,胚胎组织GSH含量和卵黄囊细胞膜流动性降低可能在铝致胚胎发育毒性中起重要作用     

相思豆毒素的内化作用

目的　研究相思豆毒素 (ABR)的内化入胞作用并探讨内化入胞的可能作用机制。方法　葡聚糖凝胶层析制备ABR的异硫氰酸荧光素 (FITC)标记探针 (FITC ABR) ;MTT比色法测定FITC ABR对体外培养人胚胎肾细胞 (HEK)增殖的抑制作用 ;激光共聚焦显微镜示踪FITC ABR的内化过程。结果FITC ABR在凝胶层析图谱中先于FITC洗脱 ,两者能较好的分离 ,所制备的FITC ABR浓度为 10 .0g·L- 1,FITC ABR与ABR在 10 0 0～ 0 .0 1μg·L- 1浓度范围内 ,以相同浓度作用于HEK细胞 ,对细胞增殖的抑制作用相似 ,两者的pIC50 均约为 16pmol·L- 1;分子荧光探针FM4 6 41.5 μmol·L- 1对体外培养HEK细胞连续标记 12h ,能特异性标记细胞膜及膜性细胞器如胞内体、溶酶体、高尔基体等 ,细胞膜及胞内分别可见连续以及散在的红色荧光 ;FITC ABR 10mg·L- 1单独标记细胞 15 ,30min ,即可见到胞内有绿色荧光 ,FITC ABR与FM4 6 4联合标记细胞 ,在胞内的某些红色荧光部位同时具有FITC ABR的绿色荧光 ,两种颜色的荧光叠加后产生棕褐色荧光 ;以0 .1mol·L- 1乳糖封闭细胞膜的ABR结合位点后 ,再以FITC ABR标记细胞 30min ,可见细胞膜的绿色荧光明显减弱 ,胞内几乎无绿色荧光。升高胞内体pH的药物NH4 Cl 1mmol·L- 1能明显增强FITC ABR对胞内各膜?     

人体口服乙醇后唾液和全血中乙醛含量的测定

目的 :研究人体单剂量口服乙醇后 ,乙醇在体内的毒性代谢产物乙醛在唾液和全血中的浓度 时间变化过程。方法 :采用高效液相色谱荧光法测定 10名健康受试者单剂量口服乙醇 0 .3g·kg-1后 4h内唾液和全血中的乙醛浓度经时过程。结果 :乙醛在唾液中的Cmax(11.5± 2 .2 ) μmol·L-1,AUC(140 2 .7± 44 7.4)min·μmol·L-1;乙醛在全血中的Cmax(1.6 8± 0 .2 5 )μmol·L-1,AUC(176 .8± 41.4)min·μmol·L-1。结论 :服用乙醇后唾液中的乙醛浓度显著高于全血中     

乙醇抑制原代大鼠星形细胞神经营养因子的基因表达

为了阐明乙醇中毒对神经系统损害的机理 ,用0 .5- 5.0 g· L-1浓度的乙醇处理原代培养的 CD新生大鼠大脑皮层星形细胞 ,用反转录 PCR和Northern印迹杂交方法同时测定神经营养因子( NGF)的基因表达水平 .结果显示 0 .5g·L-1乙醇在染毒 2 4 h后 ,NGF m RNA水平开始降低 ,5.0 g· L-1在染毒 48或 72 h后 ,NGF m RNA水平与对照组比较降低了 50 % - 58% .结果表明 ,乙醇中毒在体外可降低新生大鼠星形细胞 NGF m RNA的生成 ,这种作用可干扰神经元与胶质细胞间的正常交互作用并可能与胚胎发育期乙醇接触导致的神经病理改变有关 .     

κ-硒化角叉菜胶对大鼠红细胞膜流动性与封闭度的影响(英文)

通过测定大鼠红细胞膜荧光偏振度P和N A DH-细胞色素c氧化还原酶的变化,研究kappa-硒化卡拉胶对红细胞膜流动性和封闭度的影响。结果表明,kappa-硒化卡拉胶140mg·kg~(-1)·d~(-1)×30 d可显著降低大鼠红细胞膜荧光偏振度,即可显著提高细胞膜流动性(P<0.05),ig 140及70 mg·kg~(-1)·g~(-1)×30d可显著提高大鼠红细胞膜封闭度(P<0.05)。     

乙醇脱氢酶3的遗传多态性对摄入乙醇唾液和全血中乙醛含量的影响

目的　探讨不同乙醇脱氢酶 3(ADH3)基因型对乙醇体内氧化的影响。方法　采用PCR扩增反应测定ADH3基因型 ,将 2 2名健康受试者分为ADH31 -1 ,ADH31 -2 和ADH32 -2 3组。受试者一次po 0 .3g·kg-1 乙醇后 ,采用高效液相色谱荧光法测定 4h内唾液和全血中的乙醛浓度经时过程。结果ADH31 -1 组的乙醛唾液cmax为 (1 2 .5± 2 .3) μmol·L-1 ,AUC为 (1 .4± 0 .4)mmol·min·L-1 ;ADH31 -2 组唾液cmax为 (9.4±1 .7) μmol·L-1 ,AUC为 (1 .1±0 .3)mmol·min·L-1 ;ADH32 -2 组唾液cmax为 (8.7± 2 .2 )μmol·L-1 ,AUC为 (0 .93± 0 .1 9)mmol·min·L-1 。ADH31 -1 组的唾液中乙醛浓度显著高于ADH31 -2 和ADH32 -2 组 ,但全血中的组间差异不如唾液中明显。结论　基因型为ADH31 -1 的个体在摄入乙醇后唾液中乙醛量显著增加 ,提示ADH31 -1 个体酗酒时由乙醛引发病理损害的风险性较大     

青龙衣多糖对荷瘤小鼠红细胞膜流动性及封闭度的影响

目的探讨青龙衣多糖对红细胞膜流动性及封闭度的影响。方法按Zamudio法进行NADH-细胞色素C氧化还原酶活性的测定,并按公式计算出核瘤小鼠红细胞的封闭度,以1,6-Dipheyl-1,3,5-hexatriene(DPH)为探针剂,用荧光偏振法测定荧光偏振度(P)值和微粘度(η)研究细胞膜脂的流动性。结果两种青龙衣多糖均能使S180、H22核瘤小鼠的红细胞流动性及封闭度提高(P<0.05)。结论青龙多糖的抑瘤作用可能通过提高红细胞膜流动性及封闭度,增强维持红细胞膜的稳定性的能力并升高红细胞膜的重新封闭的能力起积极作用。     

k—硒化角叉菜胶对大鼠红细胞膜流动性与封闭度的影响

通过测定大鼠红细胞膜荧光偏振度Ｐ和ＮＡＤＨ－细胞色素Ｃ氧化还原酶的变化，研究ｋａｐｐａ－硒化卡拉胶对红细胞膜流动性和封闭度的影响。结果表明，ｋａｐｐａ－硒化卡拉胶１４０ｍｇ·ｋｇ＾－１·ｄ＾－１×３０ｄ可显降低大鼠红细胞膜荧光偏振度，即可显提高细胞膜流动性（Ｐ＜０．０５），ｉｇ１４０及７０ｍｇ·ｋｇ＾－１·ｇ＾－１×３０ｄ可显提高大鼠红细胞膜封闭度（Ｐ＜０．０５）。     

枸杞多糖抗辐射效应研究

研究表明 ,枸杞中多糖类成分 (LBP)具有较强的生理活性 ,如清除自由基[1 ] ,抗衰老[2 ] ,调节免疫[3,4 ] ,促进精细胞染色体损伤的修复[5] 等 ,但有关LBP的抗辐射作用的研究少见报道。1　材料与方法1 .1　LBP的制备　宁夏枸杞 ,取适量打碎 ,加 1 0倍的水溶液 ,捣浆 ,过滤加乙醇至 60 % ,沉淀物 60℃干燥 ,得LBP。将LBP调配成低剂量 (4g·L- 1 )、中剂量 (1 2g·L- 1 )、高剂量(2 4 g·L- 1 )水溶液备用。1 .2　动物存活率测定　昆明种♂小白鼠 ,体重 (1 7± 2 ) g ,由湖北省卫生防疫站提供。分组灌胃上述 3种剂量LBP ,剂量 0 5ml…     

乙醇对胚胎发育与卵黄囊超微结构的影响

为研究发育敏感期暴露于乙醇不同时间对胚胎发育和胚胎卵黄囊超微结构的影响 .以体外全胚胎培养和电镜技术研究 0 .2g·L- 1乙醇不同时间作用时对胚胎发育影响及胚胎卵黄囊超微结构改变 .结果表明发育异常与乙醇作用存在时间 效应关系 .0 .2g·L- 18h对胚胎发育和形态分化无明显影响 ,随时间延长除胚胎头长 ,体长 ,卵黄囊直径 ,蛋白质和DNA含量等主要发育指标进一步受抑制外 ,胚胎畸形 ,死亡率明显升高 .卵黄囊超微结构变化程度与染毒时间和胚胎发育状况相一致 ,乙醇可导致卵黄囊细胞内微绒毛和溶酶体数量减少 ,线粒体等部分细胞器内膜肿胀 .上述结果提示卵黄囊结构损伤和破坏在乙醇所致的发育异常中起重要作用     

Comparison of in vitro and in utero ethanol exposure on indices of oxidative stress

Prenatal ethanol exposure produces neural tube defects and growth retardation in experimental animals. Because ethanol's teratogenic effects may involve oxidative stress and effects may differ in vitro and in utero, glutathione, cysteine and ATP were evaluated in gestational day 10 rat conceptuses exposed to ethanol. Cultured embryos exposed to ethanol (1.5 or 3.0 mg/mL) maintained a concentration-dependent decrease in glutathione of 21 or 35%, respectively, at 6 h; visceral yolk sac (VYS) glutathione (GSH) decreased by 22 or 18%, respectively, at 3 h. Maternal ethanol exposure (4.5 g/kg) decreased glutathione by 30% in embryos and VYSs at 3 h, but values rebounded. Cultured embryonic cysteine decreased after 30 min by 42% with both doses and after 6 h by 32 or 38% with 1.5 or 3.0 mg/mL, respectively. Ethanol (1.5 mg/mL) increased VYS cysteine by 35% after 30 min. In utero ethanol exposure decreased embryonic cysteine by 58% at 3 h. Ethanol (1.5 mg/mL) decreased adenosine triphosphate (ATP) by 30-60% in embryos and VYSs at 30 min. After 6 h, embryonic ATP decreased by 41 and 30% with 1.5 and 3.0 mg/mL, respectively, while VYS ATP decreased by 38% with 1.5 mg/mL. In utero ethanol exposure decreased ATP by 31% at 3 h in VYSs. While decreases in GSH and cysteine were evident earlier in utero than in vitro, values returned to control suggesting embryos exposed in utero respond rapidly to chemical-induced oxidative stress due to maternal protective mechanisms. Differences between in vitro and in utero responses to ethanol have important implications for interpretation of in vitro developmental studies.     

Ethanol- and acetaldehyde-mediated developmental toxicity in zebrafish

Ethanol is a well-established developmental toxicant; however, the mechanism(s) of this toxicity remains unclear. Zebrafish are becoming an important model system for the evaluation of chemical and drug toxicity. In this study, zebrafish embryos were utilized to compare the developmental toxicity resulting from either ethanol or acetaldehyde exposure. Embryos were exposed to waterborne ethanol concentrations for various lengths of time but encompassed the earliest stages of embryogenesis. The waterborne ethanol concentration that causes 50% mortality (LC₅₀) following a 45-h ethanol exposure was approximately 340 mM (1.98% v/v). A number of reproducible endpoints resulted from ethanol exposure and included pericardial edema, yolk sac edema, axial malformations, otolith defects, delayed development, and axial blistering. When the exposure period was reduced, similar signs of toxicity were produced at nearly identical ethanol concentrations. To estimate the embryonic dose following a given waterborne ethanol concentration, a kinetic alcohol dehydrogenase (ADH) assay was adapted. The average embryonic ethanol dose was calculated to be a fraction of the waterborne concentration. Embryos exposed to waterborne acetaldehyde resulted in similar, but not identical, endpoints as those induced by ethanol. Embryos were however, almost three orders of magnitude more sensitive to acetaldehyde than to ethanol. Ethanol and acetaldehyde both negatively impact embryonic development; however, ethanol is more teratogenic based on teratogenic indices (TIs). These results demonstrate that the zebrafish model will provide an opportunity to further evaluate the mechanism of action of ethanol on vertebrate development.     

Spatial distribution of glutathione, glutathione-related and antioxidant enzymes in cultured mouse embryos

The present study was undertaken to evaluate the detoxifying capacity of organogenesis-stage murine concepti cultured in vitro. Investigative attention was particularly focused on the embryonic tissue distribution of cytoprotective pathways. Glutathione (GSH) status, GSH-related and antioxidant enzymes were assayed in the embryo proper (EP), visceral yolk sac (VYS) and ectoplacental cone (EC) of 29.44 ± 1.56 (mean ± SD) somite pairs concepti. All the tissues displayed significant and comparable concentrations of GSH, further supporting this tripeptide as critical in protection against embryotoxicants. The totality of enzymatic activities was detectable in the selected embryonic compartments. In terms of spatial distribution analysis, maximal activities were found in EC (glutathione peroxidase, glutathione reductase, superoxide dismutase and glyoxalase I and II), and VYS (glutathione transferase and catalase). These results indicate: (1) the organogenesis-stage conceptus, in addition to significant amounts of GSH, expresses constitutive activities of GSH-related and antioxidant enzymes; (2) maximal activity levels are detectable in the embryonic sites which, at the developmental stage selected for assay, serve (VYS) or are evolving to serve (EC) embryo/maternal exchange, and thus represent the primary sites of interaction with foreign compounds. Received: 13 March 1997 / Accepted: 18 August 1997     

Biochemical and ultrastructural alterations in the rat ventral prostate due to repetitive alcohol drinking

Previous studies showed that cytosolic and microsomal fractions from rat ventral prostate are able to biotransform ethanol to acetaldehyde and 1-hydroxyethyl radicals via xanthine oxidase and a non P450 dependent pathway respectively. Sprague Dawley male rats were fed with a Lieber and De Carli diet containing ethanol for 28 days and compared against adequately pair-fed controls. Prostate microsomal fractions were found to exhibit CYP2E1-mediated hydroxylase activity significantly lower than in the liver and it was induced by repetitive ethanol drinking. Ethanol drinking led to an increased susceptibility of prostatic lipids to oxidation, as detected by t-butylhydroperoxide-promoted chemiluminiscence emission and increased levels of lipid hydroperoxides (xylenol orange method). Ultrastructural alterations in the epithelial cells were observed. They consisted of marked condensation of chromatin around the perinuclear membrane, moderate dilatation of the endoplasmic reticulum and an increased number of epithelial cells undergoing apoptosis. The prostatic alcohol dehydrogenase activity of the stock rats was 4.84 times lower than that in the liver and aldehyde dehydrogenase activity in their microsomal, cytosolic and mitochondrial fractions was either not detectable or significantly less intense than in the liver. A single dose of ethanol led to significant acetaldehyde accumulation in the prostate. The results suggest that acetaldehyde accumulation in prostate tissue might result from both acetaldehyde produced in situ but also because of its low aldehyde dehydrogenase activity and its poor ability to metabolize acetaldehyde arriving via the blood. Acetaldehyde, 1-hydroxyethyl radical and the oxidative stress produced may lead to epithelial cell injury.     

cAMP-dependent regulation of P450-catalyzed dealkylation in rat conceptal tissues

Exposures of cultured whole rat conceptuses to varying concentrations of dibutyryl cyclic AMP or isobutylmethylxanthine, alone or in combination, resulted in significant increases in rates of cytochrome P450-dependent depentylation of pentoxyphenoxazone in cell-free preparations. Lesser increases in rates of debenzylation of benzyloxyphenoxazone were also observed. In cultured whole conceptuses, basal depentylase and debenzylase activities in the visceral yolk sac were approximately sixfold higher than in the embryo. The ectoplacental cone and decidual tissues exhibited no detectable depentylase activity. Only the visceral yolk sac exhibited increased depentylase activity in response to dibutyryl cyclic AMP and isobutylmethylxanthine. Inhibitory antibodies raised against adult hepatic P450s IIB1, IIC11, and IA1 failed to significantly inhibit the yolk sac depentylase activities of noncultured conceptuses. The results suggested that the conceptal depentylation reaction may be catalyzed by a unique P450 isoform(s) that is not expressed during adult life.     

Distribution and accumulation of 10 nm silver nanoparticles in maternal tissues and visceral yolk sac of pregnant mice,and a potential effect on embryo growth

We examined the distribution of silver in pregnant mice and embryos/fetuses following intravenous injections of 10?nm silver nanoparticles (AgNPs) or soluble silver nitrate (AgNO₃) at dose levels of 0 (citrate buffer control) or 66?µg Ag/mouse to pregnant mice on gestation days (GDs) 7, 8 and 9. Selected maternal tissues and all embryos/fetuses from control, AgNP- and AgNO₃-treated groups on GD10 and control and AgNP-treated groups on GD16 were processed for the measurement of silver concentrations, intracellular AgNP localization, histopathology and gross examination of tissue morphology. Inductively-coupled plasma mass spectrometry revealed silver in all examined tissues following either AgNP or AgNO₃ treatment, with highest concentrations of silver in maternal liver, spleen and visceral yolk sac (VYS), and lowest concentrations in embryos/fetuses. For VYS, mean silver concentration following AgNO₃ treatment (4.87?ng Ag/mg tissue) was approximately two-fold that following AgNP treatment (2.31?ng Ag/mg tissue); for all other tissues examined, mean silver concentrations following either AgNP or AgNO₃ treatment were not significantly different from each other (e.g. 2.57 or 2.84?ng Ag/mg tissue in maternal liver and 1.61 or 2.50?ng Ag/mg tissue in maternal spleen following AgNP or AgNO₃ treatment, respectively). Hyperspectral imaging revealed AgNP aggregates in maternal liver, kidney, spleen and VYS from AgNP-treated mice, but not AgNO₃-treated mice. Additionally, one or more embryos collected on GD10 from eight of ten AgNP-treated mice appeared small for their age (i.e. Theiler stage 13 [GD8.5] or younger). In the control group (N?=?11), this effect was seen in embryos from only one mouse. In conclusion, intravenous injection of 10?nm AgNPs to pregnant mice resulted in notable silver accumulation in maternal liver, spleen and VYS, and may have affected embryonic growth. Silver accumulation in embryos/fetuses was negligible.