THIAMINE DEFICIENCY AND GLYOXYLIC ACID FORMATION IN RATS

Tissue levels and urinary excretion of glyoxylic acid increase in thiamine deficient rats, presumably as a result of a decrease in the thiamine dependent decarboxylation of glyoxylic acid to carbon dioxide and formate. This increase may be an important metabolic change, since glyoxylic acid can inhibit reactions of the tricarboxylic acid cycle.     

DIETARY FATS AND INTESTINAL THIAMINE SYNTHESIS IN RATS

Animals fed thiamine deficient diets survive longer if the diet contains 75 per cent fat and no sucrose than if it includes 15 per cent fat and 60 per cent sucrose. Urinary, fecal, and tissue thiamine content and count of fecal coliform organisms are higher if the fat is relatively unsaturated.     

EXCRETION OF THIAMINE AND THIAMINE METABOLITES IN YOUNG MEN

Urinary excretion of pyrimidine and thiazole, metabolites of thiamine, has been used to estimate the minimum thiamine requirement in young men.     

壬基酚在雌性大鼠体内的分布与清除

[目的]探讨消化道摄入壬基酚(NP)后在雌性大鼠血清及组织器官内的分布与清除.[方法]48只SD雌性大鼠一次性灌胃200 mg/kg NP,在灌胃后的8个时间点分别剖杀动物取其血清、肝、肾、子宫和卵巢,测定壬基酚含量. [结果]不同时间点各组织及血清中NP含量以卵巢最高,子宫、血清最低,且各时间递减趋势为卵巢>肝>肾>子宫>血清. [结论]消化道摄入NP后,主要分布干实质性脏器,经肝脏、肾脏清除,卵巢可能为其主要受损器官.     

CARBOHYDRATE PREFERENCE IN NORMAL AND MALNOURISHED RATS

Rats raised on a diet restricted in protein will consume extra sugar when available, further lowering their protein intake.     

红细胞游离原卟啉在非缺铁婴幼儿中的分布特征及正常值探讨

本文分析了336名非缺铁婴幼儿红细胞游离原卟啉(Free Erythro-cyte Protoporphyrin,FEP)水平。结果表明,336名婴幼儿FEP呈正态分布,正常值为360μg/L全血,界限值500μg/L;FEP水平无年龄和性別的差异;FEP与Hb之间呈负相关,r=-0.6784(P<0.01);诊断铁缺乏症的灵敏性为87％,特异性88％,与Hb的诊断符合串为81％。同时比较了国产930型简易荧光计与日本F-3000型荧光分光光度计测定FEP效果,其结果基本一致,但930机测定值离散度较大。     

DISTRIBUTION AND TURNOVER OF ACETALDEHYDE-MODIFIED PROTEINS IN LIVER AND BLOOD OF ETHANOL-FED RATS

Previous studies have shown that acetaldehyde (AcH)-modifiedproteins are formed in the liver and blood of rats fed ethanol-containingdiets. in this study we report the application of ELISA techniquesto study the subcellular distribution and turnover of AcH-modifiedproteins in ethanol-fed and control rats. Modified proteinswere found in liver mitochondrial, crude membrane and cytosolicfractions, as well as in plasma from ethanol-fed rats. No adductswere detected by our assay in haemolysates from the same animals.The rate of decline of AcH-modifled proteins after cessationof ethanol feeding was also examined. Modified liver cytosolicproteins were shown to decline with a half-life of 2.3 weeks,whereas modified plasma adducts declined with a half-life of4.8 weeks.     

EARLY BRAIN STEM LESIONS IN THIAMINE DEFICIENT RATS

The early lesions of acute thiamine deficiency, when viewed by electron microscopy. show swelling of glial cell cytoplasm which is coincident with the onset of neurological signs It is postulated that these early changes represent a derangement of energy dependent electrolyte and fluid balance in neuroglial tissues.     

牛乳碱性蛋白对正常和去卵巢大鼠骨代谢的影响

目的探讨牛乳碱性蛋白(MBP)对正常大鼠和去卵巢大鼠骨代谢的影响。方法将60只去除卵巢雌性SD大鼠随机分为假手术、去卵巢对照以及去卵巢低、中、高剂量5组;将另外44只正常雌性SD大鼠随机分为正常对照、正常低、中、高剂量4组。分别采用10、20、30mg/kgbwMBP给大鼠连续灌胃90d,检测股骨近心端、中段和远心端骨密度,同时检测股骨中Ca、Mg、P等矿物元素含量。结果正常低剂量组大鼠股骨远心端骨密度显著高于正常对照组;而各剂量MBP对去卵巢大鼠的骨密度无显著作用;正常各组之间以及去卵巢组之间比较,骨矿物质含量虽无统计学差异,但可以观察到其水平上的上升趋势。结论10mg/kg.bw的MBP能提高正常生理状态下的峰值骨密度,以股骨远心端效果最好,但未见MBP对去卵巢大鼠骨密度的影响。MBP除影响骨骼中矿物元素含量外,还可能通过其他方式作用于骨代谢。     

THE EFFECTS OF TREMELLA AURANTIA ON TESTOSTERONE AND CORTICOSTERONE PRODUCTIONS IN NORMAL AND DIABETIC RATS

Tremella aurantia (TA) has been traditionally used as food and crude medicine in Chinese society. The polysaccharide isolated from the fruiting bodies of TA exhibits significant hypoglycemic activity in diabetic mouse models of insulin-dependent diabetes mellitus (IDDM) and non-insulin-dependent diabetes mellitus (NIDDM). Diabetes will cause sexual dysfunction in patients. In the present study, we examined if the treatment of TA on IDDM and NIDDM rats will restore steroidogenesis and then the reproductive function. The fruiting bodies (FB), mycelium (TM) and polysaccharide (GX) of TA were fed to the IDDM and NIDDM rats, and testosterone and corticosterone levels in plasma, the weight of steroidogenic organs, and the expression of steroidogenic acute regulatory (StAR) protein and P450scc enzyme were determined. Plasma testosterone productions were significantly suppressed with the feeding of FB or TM in normal rat (p?<?0.05). Testosterone productions were also significantly suppressed in IDDM diabetes rats (p?<?0.05), and FB or TM could not restore the inhibitory effects (p?>?0.05). There was no significant difference of the testosterone production between normal and NIDDM rats (p?>?0.05). In plasma corticosterone production, there were no differences among control, FB- or TM-fed normal rats (p?>?0.05). Corticosterone levels were reduced in IDDM rats compared to control, and FB or TM could restore its level. Corticosterone levels were induced in NIDDM rats compared to control (p?<?0.05), but FB, TM or GX significantly brought the corticosterone back (p?<?0.05) to the control levels. Considering steroidogenic organs, IDDM rats with or without TA treatments had heavier testis and adrenal glands, but not epididymis, than normal rats with or without TA treatments. There were no effects of TA on the weight of steroidogenic organs among normal and NIDDM rats. However, GX feeding in NIDDM rat had lesser testis weight compared to NIDDM rats. The expression of StAR protein and P450scc enzyme were not different among groups in IDDM and NIDDM rats. Plasma testosterone productions were suppressed in normal rats with the feeding of TA (FB and TM). IDDM rats did have lower testosterone, but not in NIDDM, and FB or TM could not restore the inhibitory effects. The induction of IDDM or NIDDM rats did affect steroidogenesis and steroidogenic organ weights, and the feeding of TA had different effects on steroidogenesis in different types of diabetic rats.     

槲皮素对大鼠体内胆固醇分布的影响

目的研究槲皮素对大鼠体内胆固醇分布的影响。方法将50只雄性Wistar大鼠以AIN-93G基础饲料适应喂养1w后,根据体重和血低密度脂蛋白胆固醇(low-density lipoprotein cholesterol,LDL-C)水平分为5组,即对照组和0.1%、0.2%、0.4%和0.8%槲皮素组。在第5w末,测定血清总胆固醇(total cholesterol,TC)、甘油三酯(triacylglyceride,TG)、高密度脂蛋白胆固醇(high-density lipoprotein cholesterol,HDL-C)及低密度脂蛋白胆固醇(LDL-C)浓度,并取心、肝、肾、小肠及睾丸组织,测定其中胆固醇(total cholesterol,TC)、游离胆固醇(free cholesterol,FCH)及胆固醇酯(cholesterolester,CE)浓度。结果补充槲皮素后,血LDL-C浓度升高,其中0.4%槲皮素组与对照组比较有统计学意义,各组血TC、TG及HDL-C浓度差异无统计学差异;心、肝、肾和小肠中TC、FCH及CE含量有所下降,但睾丸表现为上升趋势。结论槲皮素具有影响胆固醇在体内组织中分布的作用。[营养学报,2013,35(2):172-175]     

大鼠脱碘酶、硒蛋白P和硒蛋白W正常表达所需的最低饲料硒水平

目的　研究能满足大鼠脱碘酶、硒蛋白 P和硒蛋白 W合成所需的饲料硒水平。方法　以低硒酵母合成饲料加不同剂量的亚硒酸钠配成硒水平分别为 0 .0 1、0 .0 2、0 .0 3、0 .0 4、0 .0 5、0 .0 6、0 .1 0和 0 .2 0 mg/kg的 8种饲料喂养雄性 wistar断乳大鼠。 2 0周时杀死大鼠取其组织 ,分别对各种组织中的 型、 型和 型脱碘酶、硒蛋白 P的 m RNA以及硒蛋白 W的 m RNA的水平进行测定。结果　能满足大鼠各组织 型、 型和 型脱碘酶发挥最佳活性时的最低饲料硒水平为0 .0 5mg/kg,而硒蛋白 P的 m RNA以及硒蛋白 W的 m RNA正常表达所需的最低饲料硒水平分别为 0 .0 5和 0 .0 6mg/kg。结论　饲料硒水平达到 0 .1 mg/kg可满足大鼠脱碘酶、硒蛋白 P和硒蛋白 W的合成。     

铅中毒大鼠肾近曲小管内铅的分布

前人在铅中毒动物肾近曲小管上皮细胞内发现有核内包涵体。这种包涵体曾被认为含有铅.本实验用含铅饲料饲养大鼠一个月后取肾皮质,进行超微结构和X射线显微分析研究。在超薄切片中观察到,肾近曲小管上皮细胞核内有包涵体形成,管腔中可见电子致密斑块。X射线显微分析结果指出,于包涵体的中心区和周边区以及溶酶体和胞质基质中都不产生pb元素峰。只在管腔中的致密斑块中,能产生PbLa峰和CaKa峰。表明致密斑块是铅中毒动物肾内铅沉积部位。而其核内包涵体中并未见铅的沉积,它可能是细胞对铅中毒性作用的反应产物。     

ROLE OF THIAMINE IN REGULATION OF FATTY ACID AND CHOLESTEROL BIOSYNTHESIS IN CULTUREDBRAIN CELLS

Thiamine deficiency in cultured glial cells impairs their ability to synthesize fatty acids and cholesterol. The defect is related to reduced formation of key lipogenic enzymes. These changes could be the basis of degenerative changes seen in glial cells in early thiamine deficiency.