RELATIVE AND COMBINED EFFECTS OF PROPYLTHIOURACIL, ETHANOL AND PROTEIN DEFICIENCY ON MUSCLE

A hypermetabolic state with increased oxygen consumption hasbeen described in alcoholic hepatitis, playing a major rolein ethanol-induced liver damage. Based on its ability to decreaseoxygen consumption, propylthiouracil (PTU) has been proposedas a therapeutic agent in this context. On the other hand, severalmuscle changes have been described in hypothyroidism. Includingboth atrophy and hypertrophy of muscle fibres. The aim of thisexperimental study was to analyse the effects of PTU on thealcohol-induced changes in muscle fibre size and proportion,also taking into account the presence or absence of proteindeficiency. The study was performed on 64 male Wistar rats dividedinto eight groups, fed with: (1) Lieber-DeCarli control diet:(2) an isocaloric 36% ethanol-containing diet; (3) an isocaloric2% protein-containing diet: (4) an isocaloric 36% ethanol 2%protein-containing diet, without and with PTU, respectively.Right gastrocnemius muscle was removed 2 months later and histochemicaland morphometric studies were performed Type lIb fibre atrophywas observed both in the alcoholic and protein-deficient animals,but not in the PTU-treated animals. The combination of proteindeficiency and ethanol led to a more marked type IIb atrophy,with PTU reversing this effect. Malnutrition led to a decreasein type I fibre diameter; ethanol and PTU caused an increasein its size and PTU reversed the effect of protein deficiency.Proportion of type IIb fibres decreased in the three experimentalgroups without PTU with respect to the control, especially inthe alcoholic protein-deficient animals. PTU-treated animals,especially those fed a low-protein diet, showed a more markedreduction in type IIb fibre proportion than that presented bythe groups without PTU. However, an increase in type I fibreproportion was observed in the PTU-treated animals, especiallymarked in those fed a low-protein diet Thus, PTU seems to ameliorateethanol-induced changes on type IIb muscle fibres.     

RELATIVE AND COMBINED ROLES OF ETHANOL AND PROTEIN MALNUTRITION ON MUSCLE ZINC, POTASSIUM, COPPER, IRON, AND MAGNESIUM

The aim of the present study is to analyse the relative andcombined effects of ethanol and protein malnutrition on musclezinc, copper, iron, potassium, and magnesium in ethanol.fedrats. The study was performed in 32 animals divided into fourgroups, fed with the Lieber-DeCarli control, 36% ethanol, 2%protein, and 36% ethanol 2% protein containing diets, respectively.Right gastrocnemius muscle was removed 2 months later, and wasstudied both chemically and histochemical-morphometrically.Both muscle zinc and potassium, but not copper nor iron normagnesium, were significantly decreased in the protein-deprived,ethanol-fed animals, the main effect of these variations beingattributable to ethanol rather than to protein deprivation.However, coexisting protein deprivation aggravated the decreasein both muscle zinc and potassium. Both muscle zinc and potassiumwere significantly related to serum albumin, weight loss, andtype IIb fibre atrophy; and muscle zinc, in addition, to thedecrease in type IIb fibre proportion. Therefore, a decreasein muscle content of both elements is related to histochemical-morphometricalchanges observed in alcoholic myopathy. In addition, both ethanoland protein deficiency exerted independent, highly significanteffects both on type IIb fibre atrophy and proportion.     

姬松茸多糖对铅中毒大鼠铅代谢及体内铜、钙、锌、铁、锰含量的影响

目的了解姬松茸多糖(Agaricus blazei Murrill polysaccharides,ABP)对Pb中毒大鼠体内Pb、Cu、Ca、Zn、Fe、Mn含量的影响。方法选择健康45日龄SD大鼠48只,随机分为6组,每组8只,雌雄各半,分别为正常对照组、Pb中毒组、多糖组、Pb中毒+低剂量多糖干预组、Pb中毒+中剂量多糖干预组和Pb中毒+高剂量多糖干预组。Pb中毒组和Pb中毒+多糖干预组都给予0.2%醋酸铅溶液,自由饮用,其它组给予蒸馏水。多糖、低剂量、中剂量及高剂量组分别按每天每只100、50、100、200mg/kg体重灌服姬松茸多糖液,各组灌服液体积相等,为1ml。正常对照组和Pb中毒组每天每只灌胃1ml的生理盐水。饲养60d后,取大鼠肝脏、肾脏、心脏和血,分别测定Pb、Cu、Ca、Zn、Fe、Mn含量。结果 (1)与正常对照组比较,Pb中毒组各组织和三个多糖干预组中肝脏、肾脏和血中Pb含量升高,差异具有统计学意义(P<0.01),Pb中毒组心脏中的Ca、血中的Fe含量升高(P<0.05或P<0.01),其余均下降(P<0.05或P<0.01),多糖组中肾脏和心脏中的Ca,血中的Fe略有下降,其余均略有升高,差异无统计学意义。(2)与Pb中毒组比较,低剂量多糖显著降低血铅含量(P<0.01),中剂量多糖显著降低心脏中铅含量(P<0.01),其他组织铅含量差异无统计学意义,随着ABP剂量的升高,三个多糖干预组中心脏中的Ca和血中的Fe的含量逐渐降低,而其他指标均逐渐升高,当ABP剂量达到200mg/kg时,显著下降或升高(P<0.05或P<0.01)。结论姬松茸多糖促进Pb的排出,对Pb致大鼠微量元素失衡具有调节作用。     

母乳和牛奶中铜、铁、锌、锰、铬含量的比较

以原子吸收光谱法测定产后不同泌乳时期(1～90天)母乳及牛奶中铜、铁、锌、锰、铬的含量变化/结果表明,母乳中铜、铁、锌,锰的含量随泌乳期延长而下降,铬无显著变化。母乳中铜、铁、锌、铬的含量均较牛奶丰富。母乳喂养和牛奶喂养婴儿每日微量元素摄入量与其摄入推荐量相比较:母乳微量元素的营养价值较牛奶高。本研究为提倡母乳喂养,指导牛奶喂养者补充微量元素提供了科学依据。     

缺锌和补锌对大鼠血清锌、铜及血脂水平影响的研究

健康雄性Ｗｉｓｔａｒ大鼠４５只，先进行２５天锌缺乏实验，继之２１只大鼠再进行１５天锌补充实验。结果显示，缺锌可致大鼠血清总胆固醇（ＴＣ）及低密度脂蛋白胆固醇（ＬＤＬ－Ｃ）含量增高，而血清锌（Ｚｎ）、高密度脂蛋白胆固醇（ＨＤＬ－Ｃ）及其亚组分ＨＤＬ２－Ｃ含量明显下降，并且血清Ｚｎ含量与上述各指标均呈很好的剂量反应关系。适量补锌（１２ｍｇ／ｋｇ和３０ｍｇ／ｋｇ）均可使大鼠的各项指标完全恢复，而大剂量补锌（２５０ｍｇ／ｋｇ）则使ＨＤＬ－Ｃ及ＨＤＬ２－Ｃ有延迟恢复的趋向。血清铜（Ｃｕ）含量始终无明显改变。提示，膳食锌含量缺乏可致血脂代谢紊乱，而大剂量补锌又可使血脂恢复延迟，因此，膳食中Ｚｎ含量应有适当的剂量范围。     

不同地区乳汁中锌、铜、铁含量的研究

本研究收集了我国７个不同地区共１０１２份产后１～６个月乳母的乳汁进行了锌、铜、铁含量测定，结果均以产后１２天较高，其平均含量分别为４．５２±１．７０，０．５１±０．１６和１．０３±０．５３μｇ／ｇ，并随泌乳期延长而下降。不同地区乳汁中锌、铜、铁含量存在一定差异。各地区乳汁中锌含量均与乳母膳食中动物性来源锌及动物性蛋白质摄取量呈正相关。乳汁中铜含量与乳母膳食中动物性蛋白质摄取量也呈正相关。未发现乳汁中铁含量与乳母膳食中营养素的摄取量有关。     

INTERACTION OF IRON, COPPER, AND ZINC

Iron-fortified infant formulas are associated with reduced absorption of copper, but have no effect on zinc absorption.     

上海地区50种常用食物锌、铜、铁含量的测定

本文采用原子吸收法对上海地区50种常用食物作了锌、铜、铁含量的测定。结果表明,肝、肉、蛋黄和海产类上述元素的含量较多,植物性食物次之,而水果则含量极微。在各种食物中这三种元素的含量常呈正相关。虽然食物中锌和铁的含量较铜多,但由于每日锌和铁的需要量分别为铜的5倍和10倍,而且食物中的植酸盐和纤维素均能妨碍其吸收,故二者同时缺乏颇为常见。 牛乳中这三种元素的含量均不能满足小儿生长发育的需要,故对乳制品应加以强化。     

不同性别、年龄的儿童少年发样中锌、铜、铁的含量

本文从群体角度测定了北京市城区儿童少年发样中锌、铜、铁的含量,并探讨了其含量与性别、年龄的关系,认为发锌值随年龄呈现有规律的变化,是评定儿童和青少年生长发育水平的较敏感指标,而发铜、发铁值次之。     

COMPARISON OF THE ACUTE EFFECTS OF ETHANOL ON LIVER AND SKELETAL MUSCLE PROTEIN SYNTHESIS IN THE RAT

(1) The acute effects of ethanol on protein synthesis by liverand skeletal muscle were investigated in young (95–100g) rats. Rats were injected intraperitoneally with ethanol,75 mmol/kg body wt; controls were injected with isovolumetric0.15 M NaCl. After 140 min rates of protein synthesis were measuredby injection of a large dose of L[4³H]phenylalanine and at 150min rats were killed. (2) Fractional rates of protein synthesisin control animals were approximately four to five times greaterin liver than muscle. Absolute rates were, however, comparablein liver and skeletal muscle. Ethanol reduced the fractionalrate of liver protein synthesis by 5–20%; the responsefor muscle was relatively greater (25–30%). The decreasein the amount of protein synthesised by muscle was also greaterthan that by liver. (3) After 150 min, plasma gamma-glutamyltransferase, alanine aminotransferase, alkaline phosphatase,lactate dehydro-genase and creatine kinase activities were alldecreased by 25–60%. Aspartate aminotransferase activitywas increased by 42%, though this was not statistically significant.(4) Increased plasma glucose and triglycerides in ethanol-dosedrats indicated that limitations in substrate supply were notmediating factors in reducing protein synthesis. Ethanol wasalso able to exert its effects in the presence of elevated insulinlevels. A direct effect of ethanol, or its metabolites, on proteinsynthesis, is therefore implied.     

经口摄入高硒镉对大鼠肝,肾组织中镉,锌,铜含量影响的研究

选用4周龄SD大鼠,经口染毒高硒(5.68mg/kg)、富硒(0.73mg/kg)和(或)高镉(33.3mg/kg)12周,并分别在实验的第3、6、9、12周末各处死一批大鼠,研究经口摄入高硒高镉对大鼠肝、肾组织中镉、锌、铜含量的影响。结果表明:同时摄入高硒高镉组大鼠体内镉蓄积明显低于单纯摄入高镉组;对单独摄入高硒、高镉所诱导的大鼠肝脏锌含量增加表现为拮抗作用;对单独摄入高硒所致大鼠肾脏锌含量降低的影响表现为拮抗作用;对单独摄入高硒、高镉所致大鼠肾脏铜含量增加的影响表现为协同作用。     

饲料蛋白质水平对大鼠蛋白质、锌、铁和铜吸收利用的影响

Ｗｉｓｔａｒ纯品系断奶雄性大鼠３２只，随机分成４组，喂纯合成饲料。第１、２、３、４组饲料含蛋白质分别为５％、１０％、２０％和１０％，其它成份相同，第５０天只有第４组改喂以无氮饲科并与其它三组同样收集５天粪、尿，测定氮及锌、铁、铜的代谢量，第５６天处死大鼠，测毛和肝、肾、脑、睾丸、胫骨中锌、铁、铜的含量。结果表明：低蛋白质水平组影响大鼠体重增长和蛋白质代谢，机体组织锌、铁，铜含量降低，经粪便排出锌、铁量增加，锌和铁的吸收与存留显著降低。本文还对蛋白质营养水平不同所致的锌、铁、铜营养状况缺乏时毛中锌、铁、铜含量作为诊断指标的意义进行了探讨。     

锌、铜对大鼠血脂水平影响的研究

用雄性断乳ｗｉｓｔａｒ大鼠研究了不同水平锌、铜对大鼠血脂水平的影响。结果显示：绝对或相对铜缺乏均引起血清胆固醇、甘油三酯浓度升高；而绝对或相对锌缺乏则主要引起高密度脂蛋白胆固醇（ＨＤＬ－Ｃ）和ＨＤＬ＿２－Ｃ浓度下降。相关分析表明：血清锌与ＨＤＬ－Ｃ、ＨＤＬ＿２－Ｃ呈明显正相关；血清铜与血清胆固醇、甘油三酯呈显著负相关。病理检查显示：除对照组外，其它各组主动脉组织形态均发生不同程度的病理改变，尤以高锌低铜、高铜低锌及低锌低铜组为著。提示在保持适宜铜水平的前提下，补充适量的锌以提高血清ＨＤＬ－Ｃ水平，可预防或延缓高脂血症的发生。     

实验性动脉粥样硬化对血清铜、锌、铬、锰、硒的影响

本研究观察高胆固醇血症和实验性动脉粥样硬化形成对必需微量元素Cu、Zn、Cr、Mn、Se代谢的影响。将22只家兔随机分为动脉粥样硬化造型组和对照组。造型组每只家兔每天喂胆固醇0.5g,该组在形成高胆固醇血症和动脉粥样硬化的4个月过程中,血清Cu均值逐渐升高,Zn逐渐降低,Ca/Zn比值逐渐增大,前后对比差异显著。对照组血清Cu、Zn无显著变化。两组的血清Cu、Zn同次测定值对比有显著或高度显著差异。血清Cr、Mn、Se均无显著变化。相关性检验证实,造型组血清胆固醇均值与血清Ca均值无显著相关(P>0.5),而与血清Zn均值呈高度负相关(P<0.01)。结果表明,在形成实验性动脉粥样硬化的过程中,高胆固醇食物及高胆固醇血症可引起血清Zn降低,又通过锌铜拮抗,使血清Cu升高。     

微量元素铜,锌,锰与食管癌发病关系的研究

本研究用原子吸收分光光度法测定了食管癌高发区食管上皮细胞正常、轻度增生、重度增生人群及食管癌患者血清中的铜、锌及锰的含量。结果表明,随着食管上皮细胞病变的进展,血铜明显升高、血锌逐渐下降,统计学处理有非常显著差异。血清锰含量在各组间未见明显变化。结果提示食管癌患者的高血铜可能系肿瘤发生后的继发性改变,而低血锌则可能是食管癌发生的原因之一。     

铁缺乏时淋巴细胞增殖反应改变的实验研究

本研究采用体外细胞培养，３Ｈ－Ｔｄｒ掺入，原子吸收光谱分析等技术方法，观察了低浓度Ｆｅ－ｃｉｔ时淋巴细胞内铁浓度变化及经ＣｏｎＡ、ＰＨＡ诱导的细胞增殖反应能力改变，结果显示：铁缺乏时（第２、３、４组）ＳＩ降低，与正常组（第１组）比较相差非常显著（Ｐ＜０．０１），ＳＩ与细胞内铁浓度的变化呈显著正相关（Ｐ＜０．０５，ｒ１＝０．９４６６，ｒ２＝０．９３３９），说明铁缺乏时淋巴细胞增殖反应能力受抑。     

镉对机体铜,锌含量的影响

作者研究了螺蛳对镉的生物富集,镉进入生物体后,体内铜水平明显下降。40只成年雌鼠分成5组,1组对照,4组染毒,所有染毒组给以40ppm(以Cd计)氯化镉溶液,其中三组分别再加铜、锌和铁。研究进行了共六个月。结果表明:对照组无异常发现,染毒组出现骨质疏松和皮质变薄,骨中铜水平明显下降。48只成年大鼠分成三组(雌雄各半),A组为对照组,B组喂以采自镉污染区的镉米,C组同样喂镉米再给10ppm(以Cd计)氯化镉溶液。实验共进行了两个月。染毒组骨锌明显下降。上述结果表明,镉所致缺铜或缺锌,在痛痛病发病机理中,可能是一个重要的因素。     

DIFFERING EFFECTS OF CARBOHYDRATE, FAT AND PROTEIN ON THE RATE OF ETHANOL METABOLISM

The rate of metabolism of ethanol in humans has been assessedby intravenous infusion of ethanol/saline under feedback controlto maintain a constant blood alcohol concentration. After equilibration,meals consisting predominantly of carbohydrate, fat or proteinwere eaten and changes in ethanol metabolic rate were found.Carbohydrate caused a significant increase in this rate andfat or protein caused small but non-significant decreases. Infusionof ethanol/saline resulted in a temporary fall in plasma freefatty acid levels and a steady rise in plasma triglycerides.The changes in alcohol metabolism following carbohydrate cannotbe accounted for by changes in insulin, free fatty acid or lactate/pyruvatelevels.     

锌对神经细胞增殖周期DNA和蛋白质的影响

目的　研究锌对人胚大脑皮质神经细胞增殖周期 DNA和蛋白质含量的影响。方法　在建立原代培养的人胚大脑皮质神经细胞模型的基础上 ,采用免疫组织化学染色和流式细胞术进行研究。结果　 (1 )锌促进神经细胞的存活作用具有剂量效应关系。 0 .2～ 4.0 mg/L锌实验组神经细胞存活数显著高于对照组 (P<0 .0 1 ) ,且 2 .0 mg/L锌实验组为最佳剂量组。6.0 mg/L锌组神经细胞存活数显著低于对照组 (P<0 .0 1 )。(2 ) 7、1 4和 2 1 d锌实验组神经细胞 DNA和蛋白质含量均显著高于对照组 (P<0 .0 1 )。 (3)锌实验组的增殖指数、S和 G2 +M期细胞百分率高于对照组 ,G0 /G1期细胞百分率则低于对照组 (P<0 .0 1 )。结论　一定剂量范围内的锌能促进神经细胞增殖、DNA复制和蛋白质合成     

淀粉铁、蔗糖铁对铁缺乏大鼠的补铁效应

淀粉铁和蔗糖铁是糖和铁的络合物,本实验以相当于5～6mgFe/kg bw/d的淀粉铁或蔗糖铁连续灌胃大鼠24天。并以硫酸亚铁和普通饲料为对照,实验结果表明,淀粉铁组,蔗糖铁组,硫酸亚铁组和普通饲科组的血清铁含量(SIμg/dl)分别为111.08±22.3、118.64±26.80、136.80±54.36、83.44±22.60;血清铁蛋白含量(SFng/ml)分别为12.69±3.19、14.52±1.98、16.91±2.02、7.51±2.09;血红蛋白含量(Hbg/dl)分别为10.71±0.61、10.96±0.45、11.01±0.84、8.46±1.27,淀粉铁、蔗糖铁可被大鼠机体吸收并利用。