生长激素在去垂体大鼠体内的生物活性测定

目的：建立测定生长激素（ＧＨ）在体生物活性的方法。方法：以去垂体大鼠体重增长（ＢＷＧ）和胫骨骺软骨板宽度（ＴＥＷ）为指标，观察动物性别，给药途径，次数和周期不同对效应的影响，同时进行４－ｄＢＷＧ，６－ｄＢＷＧ和６－ｄＴＥＷ法，测定ＧＨ的效价（平行线３×３设计）。结果：♀和♂ｓｃ和ｉｍ给药以及每日给药１次和２次的ＢＷＧ和ＴＥＷ差异无显意义。给药６ｄ比给药４ｄ引起较大的ＢＷＧ和ＴＥＷ（Ｐ〈０．０５）     

聚乙二醇化人重组生长激素对去垂体幼鼠脏器功能的影响

目的 探讨聚乙二醇化重组人生长激素(PEG-rh GH)对去垂体幼鼠主要脏器的影响。方法 SD雄性幼鼠随机取88只进行去垂体手术造模,另18只假手术组为对照组。术后2周,选成模幼鼠54只,分为模型组、重组人生长激素(rh GH)组、PEG-rh GH组。每晚sc生理盐水0.25 mg/kg,并且rh GH组每晚sc注射用重组人生长激素0.25 mg/kg,PEG-rh GH组每周第1天晚上sc注射用重组人生长激素1.40 mg/kg。治疗4周后,检测肝功能ALT、AST、TBIL、DBIL水平,肾功能BUN、CREA水平,心肌酶谱CK、CKMB及肝脏、心脏、肾脏的病理组织和肝脏的转录生长因子β1(TGF-β1)和肾脏C-fos蛋白表达。结果 肝功能中AST、TBIL水平下降;肾功能中CREA水平升高;肝脏、肾脏、心脏病理未见明显异常;肝脏TGF-β1、肾脏C-fos蛋白表达组间无差异。结论 PEG-rh GH对肝脏、肾脏、心脏的组织形态和功能无明显不良影响。     

BAEE法测定重组水蛭素的生物活性

目的建立重组水蛭素的生物活性测定方法。方法用BAEE(N-苯甲酰-L-精氨酸乙酯)作底物,通过测定反应体系中未被水蛭素抑制的凝血酶的量,来间接测定水蛭素抗凝血酶的活力。结果重组水蛭素的生物活性测定曲线在3.2~12.8 ATU之间线性关系良好,回归方程为Y=-0.034 8X+0.7,r=0.999 3。结论BAEE法经济、便捷、准确可靠、重现性好,适宜作为该品种的生物活性测定方法。     

聚乙二醇化重组人生长激素对去垂体幼鼠胰岛分泌的影响及其机制

目的观测长效生长激素聚乙二醇化重组人生长激素(PEG-rhGH)是否引起胰岛素抵抗及其与短效生长激素注射用重组人生长激素(rhGH)的差异。方法 3周龄SD雄性幼鼠106只,随机取88只进行去垂体手术造模,取成模的幼鼠54只分为模型组、rhGH组、PEG-rhGH组,另18只假手术组为对照组。分别给予生理盐水(0.25 mg·kg-1·d-1)、rhGH(0.25mg·kg-1·d-1)、PEG-rhGH(1.4 mg·kg-1·周-1)处理。4周后进行糖耐量实验和胰岛素释放试验,计算胰岛素曲线面积与葡萄糖曲线面积比值,胰岛素稳态模型(HOMA-IR);检测血清生长抑素水平;免疫组织化学法检测胰岛胰岛素(INS)、胰高血糖素(GLU)、生长抑素(SS)、胰多肽(PP)。结果 PEG-rhGH组HOMA-IR较对照组、模型组低(P<0.05),与rhGH组比较无差异。AUCI/AUCG值组间比较显示PEG-rhGH组高于rhGH组,但无统计学差异。PEG-rhGH组GLU蛋白表达与模型组表达无差异。PEG-rhGH组INS表达较模型组表达上升(P<0.05)。PEG-rhGH组SS、PP表达与rhGH无差异。血清SS各组间均无明显差异。结论未观察到PEG-rhGH引起去垂体大鼠胰岛素抵抗和胰岛β细胞分泌能力下降,对胰岛分泌蛋白的表达无明显影响。     

Carboxylate groups in bovine somatotropin involved in growth promoting activity*

Modification of approximately one fifth of the carboxylate groups in bovine somatotropin with a water soluble carbodiimide caused loss of growth promoting potency pointing to the existence of residues related to the hormonal activity among those belonging to a fast reacting set. A sigmoidal curve was obtained whether the inactivation process was referred to reaction time or degree of modification. Isoelectrofocusing of derivatives released the native hormone from responsibility for the biological potency exerted by preparations with 1.5–2.6 modified carboxylate groups. Examination of the individual reaction kinetics of the 11 fast reacting residues, in turn, excluded the possibility of the sigmoidal character of the inactivation curve being caused by a nonexponential disappearance of essential residues, as a possible consequence of the chemical modification of others. According to synthetic models, the experimental curve may be the consequence of the effect of cumulative modification of 2 or 3 out of a set of 3 to 8 relevant residues.     

共轭亚油酸对肥胖模型大鼠减肥作用的研究

以Wistar大鼠为模型鼠，建立了肥胖大鼠模型。经口给予肥胖大鼠共轭亚油酸36d，低、中、高剂量组均能极显著减少体重的增长，低剂量组能显著性降低体内脂肪重量。中、高剂量组均能极显著性降低体内脂肪重量，且对大鼠无明显损害。高剂量组能显著降低腿部肌肉组织脂肪含量，增加蛋白质含量。表明共轭亚油酸具有一定的减肥作用。     

Evaluation of genotoxic damage of cadmium chloride in peripheral blood of suckling Wistar rats

The aim of this study was to evaluate possible genotoxic damage of cadmium chloride exposure in suckling rats by means of the comet assay and the in vivo micronucleus test of rat blood lymphocytes, because no information is available on the genotoxic effect of cadmium in rats at this early age. Pups were receiving cadmium (as CdCl(2).H(2)O) orally in fractions of 0.5 mg for 9 days, totalling 4.5 mg Cd kg(-1) body wt, or were given a single subcutaneous injection of 0.5 mg Cd kg(-1) body wt. Some pups in both exposed groups were receiving calcium supplement (CaHPO(4).2H(2)O) in feed to reduce the body load of cadmium. Control pups did not receive either cadmium or calcium supplement. Cadmium in the carcass and organs was measured by atomic absorption spectrometry. The results showed that the cadmium body burden was significantly lower when the animals were receiving calcium supplements along with oral cadmium. The results of the micronucleus and comet assays showed significant differences between the control and exposed groups, regardless of the route of cadmium administration. The only statistically significant difference between the two exposed groups (oral cadmium and oral cadmium + calcium supplements) was in the number of micronuclei. The results of the comet assay showed that tail length differed statistically only between the control and all exposed groups, regardless of the route of cadmium administration. It can be concluded that the applied cadmium doses caused detectable genome damage but it was lower in calcium-treated pups receiving cadmium orally.     

大量体液样品中螺旋霉素的效价测定

本文采用自制大块平板玻璃烧养皿和琼脂井式扩散微生物法测定了人体血清和唾液样品中螺旋霉素的含量。结果表明，本法能简便、准确地测定大批量生物体液样品中抗生素含量，精密度（ＣＶ）优于１０％。     

Metabolism of ferulic acid in rats

Ferulic acid is the major active constituent in many natural Chinese medicinal herbs. The metabolism of ferulic acid has been investigated using solid-phase extraction and HPLC-DAD methods that were established to separate and analyze the metabolites in urine, feces and bile. Three metabolites, identified by enzymatic hydrolysis, HPLC-DAD, HPLC-MS and MS/MS, are all glucuronic acid conjugates of ferulic acid. Ferulic acid conjugated with one glucuronic acid at different positions produces M1 and M3. Ferulic acid conjugated with two glucuronic acids produces M2, which is the main metabolite. A metabolic pathway is proposed.     

Developmental toxicity study of CBLB502 in Wistar rats

CBLB502 is a derivative of a microbial protein that binds to Toll-like receptor 5. It is demonstrated to reduce inflammatory response from acute stresses, such as radiation in animal models. We determined the potential developmental toxicity of CBLB502 in rats. Four groups of 25 time-mated female Wistar rats/group received subcutaneously 0, 30, 100, or 300 μg/kg/day of CBLB502 from Gestation Days (GD) 6 to 17 at a dose volume of 1.0 mL/kg. Toxicokinetic evaluation was performed on GD 6 and 17. On GD 20 C-section was performed for uterine evaluation and blood samples collected from each dam for immunogenicity assay.Significant decrease in gestation body weight, weight changes and food consumption indicative of maternal toxicity were observed in all dose groups. Also adjusted body weight and weight changes were seen at 300 μg/kg/day. No external, visceral and skeletal abnormalities were observed. The NOAEL for developmental toxicity was estimated to be ≥300 μg/kg/day.     

高同型半胱氨酸和高胆固醇血症联合作用对大鼠基因组DNA总甲基化状态的影响

目的:探讨高同型半胱氨酸血症(HHCY)和高胆固醇血症(HTC)联合作用对大鼠主动脉基因组DNA总甲基转移酶活力(DNMT)及总甲基化水平的影响.方法:44只健康清洁级成年Wistar雄性大鼠按2×2析因设计随机分为阴性对照组、高同型半胱氨酸(HCY)组、高总胆固醇(TC)组、高HCY+高TC组,每组11只.对照组给予普通大鼠饲料,其余各组给予相应的配方饲料.喂养3个月后心脏取血检测血清中HCY、TC等相关指标.提取主动脉基因组DNA检测基因组DNA总甲基化水平;提取主动脉核蛋白检测基因组DNA总甲基转移酶活力.结果:HHCY和HTC联合作用大鼠血清HCY较高,产生相可作用(P＜0.01),表现为协同作用,而对大鼠血清TC、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)无交互作用.HHCY和HTC联合作用主动脉基因组DNA总甲基转移酶活力较高,产生相互作用(P＜0.01),表现为协同作用,总基因组DNA甲基化水平降低,即去甲基化程度的增加,产生相互作用(P＜0.01),表现为协同作用.结论:HHCY和HTC联合作用使得大鼠主动脉基因组DNA总DNMT活力增高,基因组DNA总甲基化水平降低,可能是AS发生发展的重要机制之一.     

丹皮酚体外抑制TGF-β诱导的成纤维细胞增殖的研究

目的:观察丹皮酚影响下离体成纤维细胞的增殖情况,为预防因成纤维细胞增殖引起的一系列病理过程提供理论依据。方法:取10只健康Wistar大鼠用于培养成纤维细胞,将离体大鼠腹膜成纤维细胞平均分为4组,分别加入细胞培养液RPMI-1640,RPMI-1640 TGF-β,RPMI-1640 丹皮酚,RPMI-1640 TGF-β 丹皮酚。测定各培养液中成纤维细胞增殖情况,并进行比较。结果:单独使用丹皮酚不影响成纤维细胞的增殖(P>0.05),单独使用TGF-β可以刺激成纤维细胞活化进入增殖状态(P<0.01),加入丹皮酚的干预后成纤维细胞的增殖率明显下降(P<0.01)。结论:TGF-β可以促进成纤维细胞活化,丹皮酚有抑制活化的成纤维细胞增殖的作用,应用丹皮酚可能在一定程度上减轻病理状态下成纤维细胞对人体的损害。     

前列腺素E1对大鼠肝热缺血再灌注期微循环的影响

目的 研究肝热缺血再灌注（I/R）期微循环变化及前列腺素E1（PGE1）对肝微循环的保护作用,并探讨门静脉途径给药改善肝微循环的可行性。方法 选择Wistar大鼠20只,随机分为实验组和对照组,按Misra法建立肝原位热I/R模型,通过倒置显微镜活体观察模型复制前、后,再灌注前、后以及经门静脉给药后肝中央静脉的管径、血流变化、肝窦开放数,并进行血清生化检测及肝组织病理检查。结果①肝热缺血恢复再灌注后肝中央静脉直径较复制模型前明显变窄（P<0.05）,血流速度明显减慢（P<0.05）,肝窦开放数明显变少（P<0.01）,肝窦血流速度明显减慢（P<0.01）;②热I/R期用药后肝中央静脉管径较用药前明显增宽（P<0.05）,肝中央静脉血流速度实验组较对照组明显增快（P<0.05）,肝窦开放数、血流速度、扩张程度实验组均优于对照组（P<0.01）;③血清生化指标实验组好于对照组（P<0.05）;④病理检查:实验组肝窦扩张、肝窦开放数好于对照组,肝细胞浊肿变性或坏死轻于对照组（P<0.05）。结论①肝脏热I/R期存在严重的微循环障碍和再灌注损伤;②PGE1能有效地改善肝热I/R期的微循环障碍,保护肝微循环,减轻肝组织再灌注损伤;③活体再灌注期经门静脉途经给药对改善肝微循环效果确切、可行。     

重组人白细胞介素11生物学活性测定方法研究

目的建立重组人白细胞介素 11(rhIL 11)生物活性测定方法。方法运用单克隆方法筛选出rhIL 11敏感细胞株T 10 ,采用溴化四唑蓝比色法进行rhIL 11生物活性测定 ,采用四参数方程对测定结果进行计算。结果以世界卫生组织国际标准品作为参照品 ,与美国Genetics公司rhIL 11上市产品NeumegaTM进行测定比较 ,结果显示国内同类产品与其生物活性一致 ,RSD均小于 10 %。结论此方法可用于rhIL 11生物活性测定     

Toxicological evaluation of Yulangsan polysaccharide in Wistar rats: A 26-week oral gavage study

Although numerous studies have proven the medicinal values of Yulangsan polysaccharide (YLSP), the toxicity of this active ingredient is unknown. In the acute toxicity study, a single oral administration of 24 g/kg YLSP caused neither toxicological symptoms nor mortality, and the LD₅₀ was estimated >24 g/kg. In the chronic toxicity study, we administered doses of 0, 0.6, 1.2 and 2.4 g/kg YLSP in rats by oral gavage for 26 weeks followed by a 3-week recovery period. There was no mortality or remarkable clinical signs observed during this 26-week study. Additionally, there were no toxic differences in the following parameters: body weight, food consumption, hematology, clinical biochemistry, organ weight, and macroscopic findings. There were no adverse effects on histopathology observed in males or female rats treated with YLSP. Based on the results, the no-observed-adverse-effect-level of YLSP in rats is greater than 2.4 g/kg when administered orally for 26 consecutive weeks.     

Biochemical alterations induced by acute oral doses of iron oxide nanoparticles in Wistar rats

Magnetic iron oxide nanoparticles with appropriate surface chemistry have been widely used with potential new applications in biomedical industry. Therefore, the aim of this study was to assess the size-, dose-, and time-dependent effects, after acute oral exposure to iron oxide-30 NP (Fe₂O₃-30), on various biochemical enzyme activities of clinical significances in a female Wistar rat model. Rats were exposed to three different doses (500, 1,000, and 2,000?mg/kg) of Fe₂O₃-30 and Fe₂O₃-Bulk along with control. Fe₂O₃-30 had no effect on growth, behavior, and nutritional performance of animals. Fe₂O₃-30 caused significant inhibition of acetylcholinestrase in red blood cells as well as in brains of treated rats. Further, more than 50% inhibition of total, Na⁺-K⁺, Mg²⁺, and Ca²⁺-ATPases activities, as observed in brains of exposed female rats, may be the result of disturbances in cellular physiology and the iono-regulatory process. Activation of the hepatotoxicity marker enzymes, aspartate aminotransferase and alanine aminotransferase, was recorded in serum and liver, whereas inhibition was observed in kidney. Similarly, enhancement of lactate dehydrogenase activity was observed in serum and liver; however, a decrease in enzyme levels was observed in kidneys of Fe₂O₃-30-treated rats. On the other hand, Fe₂O₃-Bulk did not depict any significant changes in these biochemical parameters, and alterations were near to control. Therefore, this study suggests that exposure to nanosize particles at acute doses may cause adverse changes in animal biochemical profiles. The use of the rat model signifies the correlation with the human system.     

Differences in hepatic expression of genes involved in lipid homeostasis between hereditary hypertriglyceridemic rats and healthy Wistar rats and in their response to dietary cholesterol

Differences in expression of mRNA of genes regulating lipid and drug metabolism between hereditary hypertriglyceridemic rats (HHTg, accepted model of metabolic syndrome) and healthy Wistar–Kyoto (WKY) rats were studied. Also, differences in expression due to intake of high cholesterol diet (1% w/w) were determined to investigate possible differences in response of the WKY and HHTg rats to increased intake of dietary cholesterol. Levels of ATP-binding cassette transporters (ABCG5, ABCG8), fatty acid synthase (FAS) and cytochrome P450 (CYP2C11) mRNA were significantly lower in HHTg rats on standard laboratory diet; in contrary, CYP7A1, CYP2C6 and CYP2B2 gene expression was significantly higher. The WKY rats responded to high cholesterol diet by an increase in expression of mRNAs for sterol regulatory element binding protein (SREBP1c), CYP2B2 and CYP7A1; lower expression was found in the FAS, ABCG5, ABCG8, CYP4A1, CYP4A2 and acyl-CoA oxidase. HHTg rats responded to cholesterol intake in a similar manner, however, differences were found in expression of the FAS and CYP4A1 mRNA (decrease was not observed), CYP2B2 (decrease instead of an increase). Conclusions: (i) dietary cholesterol significantly influences expression of genes involved in lipid homeostasis and drug metabolism, and (ii) the HHTg rats responded to dietary cholesterol in a different way.     

Human vascular endothelial growth factor B: characterization of recombinant isoforms and generation of neutralizing monoclonal antibodies

1. The vascular endothelial growth factor (VEGF) family is a focus of interest with respect to novel therapies for cardiovascular disease. Members of this family bind differentially to three receptor tyrosine kinases, namely VEGF-R1, -R2 and -R3, and to the semaphorin receptors neuropilin 1 and 2. The role of VEGF-R1 and the factors that interact exclusively with this receptor (VEGF-B and placenta growth factor) has remained controversial. 2. To further elucidate the role of VEGF-B in blood vessel formation and function, we have expressed, purified and refolded both naturally occurring VEGF-B isoforms and a truncated amino acid 10-108 form. All refolded proteins have been demonstrated to bind to VEGF-R1 with appropriate kinetics in biosensor-based analysis. 3. Robust cell assays for VEGF-R1 ligands, such as VEGF-B, have been problematic. We have developed an assay based on a chimeric receptor consisting of extracellular domains 1-4 of VEGF-R1 and the transmembrane and intracellular domains of gp130. The cell line expresses luciferase to high levels 24 h after exposure to VEGF-A and both refolded VEGF-B167 and the short 10-108 isoform have been demonstrated to be active in this assay. 4. The novel cell-based assay, in combination with a variety of immunochemical approaches, has been used to identify and characterize monoclonal antibodies that neutralize VEGF-B activity.     

Anti-diabetic activity of Emblica officinalis in animal models

The aqueous extract of Emblica officinalis Gaertn. (syn: Phyllanthus emblica L.) (Euphorbiaceae) seeds was investigated for its anti-diabetic activity in animal models. Streptozotocin (STZ)-induced type 2 diabetes models were used for the study. The standardized doses of 100, 200, 300, and 400?mg kg^?1 body weight of the extract were administered orally to normal and diabetic rats in order to define its glycemic potential. The maximum fall of 27.3% (p?<?0.001) in the blood glucose level of normal rats was observed at 6?h during fasting blood glucose studies, with the dose of 300?mg kg^?1 identified as the most effective dose. The same dose produced a fall of 25.3% (p?<?0.001) in the same models during the glucose tolerance test (GTT) at 3?h after glucose administration. However, the dose of 300?mg kg^?1 of aqueous seed extract in sub- and mild-diabetic animals produced a maximum fall of 34.1 and 41.6% (p?<?0.01), respectively, during the GTT at 3?h after glucose administration. This evidence clearly indicates that the aqueous extract of E. officinalis seeds has definite hypoglycemic potential as well as anti-diabetic activity.     

Effect of oral exposure to acrylamide on biochemical and hematologic parameters in Wistar rats

The toxic effects of ACR monomer include carcinogenesis, cellular genotoxic, and neurotoxicity. In this study, we examined the effect of acrylamide on biochemical and hematologic parameters in Wistar rats and explored the renal and hepatic function of these animals through a complementary anatomopathologic study. For it, thirty female Wistar rats aged 4 weeks and weighing 100?±?10?g were housed six animals per cage and divided as follows: two groups were exposed for 2 months to drinking water containing 5 mg (Group 2) or 10?mg acrylamide (Group 3); one group of 12 rats received the median lethal dose of acrylamide by gavage (Group 4); and the control group (Group 1) received pure water. The results clearly showed that acrylamide affects various biochemical parameters, such as creatinine, urea, and serum globulin levels and the lipid balance, which are directly related to renal and hepatic dysfunction and disruption of the hematologic system. In addition, the data revealed changes in the complete blood count (CBC); significant increases in the number of leukocytes (9.95?±?1.44 and 10.44?±?1.21) and lymphocytes (6.11?±?0.48 and 6.33?±?0.76) in Groups 3 and 4, respectively; and decreases in total protein (88.95?±?6.36), albumin (37.65?±?1.65) and α-1 globulin levels (24.84?±?2.10) in Group 3. The anatomopathologic study confirmed liver damage in the animals administered an acrylamide containing diet compared with those in the control group. The present study confirmed the effects of acrylamide on different hematologic, biochemical and immunologic parameters, with a specific focus on the liver and kidney, and on the induction of neurotoxic disorders. The results showed that oral exposure to acrylamide via drinking water or gavage induces kidney damage, hepatocellular insufficiency and chronic liver disease, resulting in primary immunodeficiency and activation of the immune system following the possible expression of certain immunoreaction genes.