镉中毒对鸡体内GSH-Px、SOD的影响及硒颉颃效应的研究

选用90只100日龄依沙褐公鸡,随机平均分为3组,对照组饲喂基础日粮,加镉组饲喂基础日粮 CdCl2150 mg/kg,加硒镉组饲喂基础日粮 CdCl2150 mg/kg Na2SeO322 mg/kg,通过在日粮中添加一定剂量的镉或硒与镉,建立亚慢性镉中毒及硒颉颃模型;亚慢性镉中毒可致鸡体内血清和肝脏谷胱甘肽过氧化物酶、超氧化物歧化酶活性降低,构成了镉损伤肝脏的病理学基础。加硒后可有效地提高机体的抗氧化能力。     

黄芪复方剂提取物总黄酮对四氯化碳致大鼠肝损伤保护作用研究

目的:探讨黄芪复方剂提取物总黄酮(EFA)对CCl4致大鼠肝氧化损伤的保护作用及机制。方法:将雄性SD大鼠60只随机分成4组,即灌胃灭菌生理盐水空白对照组和模型组、联苯双酯(100 mg/kg)溶液阳性药物对照组、黄芪复方剂提取物总黄酮(200 mg/kg)组。除空白对照组腹腔注射等量生理盐水外,其余各组腹腔注射四氯化碳玉米油(2 mL/kg)造成大鼠肝氧化损伤模型,后分别于12、24 h将相应大鼠处死,检测血清中ALT、AST、ALB含量与肝组织中MDA、SOD、GSH-PX活性。结果:与模型组比较,经黄酮药物组预防性治疗后,AST、ALT转氨酶明显降低(P<0.05),而ALB含量增加不明显;同时肝脏中MDA含量明显降低(P<0.05),SOD、GSH-PX活性接近空白组,且明显高于模型组(P<0.01)。结论:EFA对四氯化碳造成的大鼠肝氧化损伤具有保护作用。     

重金属铅暴露对家蚕组织GSTs和GSH-Px酶活力及基因表达的影响

谷胱甘肽S-转移酶(GST)和谷胱甘肽过氧化物酶(GSH-Px)是生物体内重要的解毒酶。为了研究重金属铅对鳞翅目昆虫的影响机制,给家蚕添食Pb(NO3)2进行Pb2+暴露,用酶活测定和real-time PCR方法,调查家蚕5龄6 d幼虫不同组织中酶活性及相关基因mRNA转录水平的变化。正常家蚕5龄6 d幼虫生殖腺中的GST酶活性分别是脂肪体和中肠中的20.0倍、34.6倍,GSH-Px酶活性分别是脂肪体和中肠中的57.7倍、46.6倍。幼虫食下含10 mg/kg Pb2+以上的人工饲料时,生殖腺中2种解毒酶的活性成倍下降;人工饲料含20～80 mg/kg Pb2+时,生殖腺中的Gstd1和Gsh-Px基因mRNA转录水平也显著下调,且雄性比雌性更加显著。幼虫食下含10～160 mg/kg Pb2+的人工饲料时,脂肪体中2种解毒酶活性显著升高,Pb2+对2种酶的影响浓度分别为10～160 mg/kg和20～80 mg/kg,但在20～80 mg/kg Pb2+范围内,Gsh-Px和Gstd1基因mRNA的转录却受到抑制,并且雌性幼虫脂肪体中的GSH-Px酶活性及其基因mRNA转录水平、雄性幼虫脂肪体中的GST酶活性及基因mRNA转录水平对Pb2+暴露更加敏感。幼虫食下含20 mg/kg Pb2+以上的人工饲料时,中肠的GST酶活性显著上升,而GSH-Px酶活性变化较小,性别间差异不明显;Gstd1基因mRNA转录水平有上调趋势,Gsh-Px基因mRNA转录水平则受到显著抑制。结果显示,家蚕幼虫生殖腺虽然有比脂肪体和中肠更强的GST酶和GSH-Px酶活性,但对Pb2+的毒害敏感,雄性比雌性受影响更大,生殖腺通过抗氧化防御系统抵御Pb2+毒害的作用很弱。     

黄芩素对镉中毒大鼠体质量、器官系数和血液生理指标的影响

将24只SD大鼠随机均分为4组,分别为对照组、镉组、黄芩素组和黄芩素+镉组,每组6只。对照组每天用生理盐水灌喂;镉处理组按2mg/kg的Cd2+每天腹腔注射氯化镉溶液;黄芩素组每天灌服黄芩素溶液(100mg/kg);黄芩素+镉组大鼠每天腹腔注射含2 mg/kg Cd2+的氯化镉溶液,再灌服黄芩素(100 mg/kg)溶液。每周测大鼠体质量,4周后,采集大鼠血液,用血细胞分析仪测定大鼠血液生理指标,并处死大鼠,收集肝脏、肾脏、睾丸和心脏,计算器官系数。结果显示,与对照组相比,镉处理组大鼠体质量极显著下降(P0.01),肝脏器官系数显著升高(P0.05),睾丸器官系数极显著降低(P0.01);白细胞(WBC)数目极显著升高(P0.01),红细胞数目(RBC)和平均红细胞血红蛋白浓度(MCHC)显著降低(P0.05),血红蛋白(HGB)、平均红细胞血红蛋白含量(MCH)和红细胞压积(HCT)极显著降低(P0.01),其他指标差异不显著(P0.05)。与对照组相比,黄芩素组大鼠体质量、器官系数及血液生理指标无显著性差异。与镉组相比,黄芩素+镉组大鼠第3周和第4周体质量显著增加(P0.05),WBC数目显著降低(P0.05),HGB、RBC、MCHC、MCH和HCT显著升高(P0.05),而MCV、PLT、MPV、PDW差异不显著(P0.05)。结果表明,镉对大鼠的体质量、肝脏和睾丸器官系数、血液指标有影响,黄芩素对镉致大鼠损伤有一定的保护作用。     

钒对小鼠肌肉中谷胱甘肽过氧化物酶活性的影响

观察钒对小鼠肌肉中谷胱甘肽过氧化物酶(GSH-PX)活性的影响。用健康小鼠32只,随机分为4组。Ⅰ、Ⅱ、Ⅲ组分别混饮10、5、2.5 mg/kg的偏钒酸铵,Ⅳ组为对照组,饮用蒸馏水,持续饮用20 d,利用谷胱甘肽过氧化物酶测试盒测定肌肉中的GSH-PX活性。结果表明,Ⅰ组肌肉中GSH-PX活性降低极显著(P<0.01),Ⅱ组显著降低(P<0.05),Ⅲ组肌肉中GSH-PX活性升高,但差异不显著(P>0.05)。说明偏钒酸铵在5 mg/kg~10 mg/kg剂量范围内可使肌肉中谷胱甘肽过氧化物酶活性降低。     

一氧化氮合酶阳性神经元在大鼠体内的分布与一氧化氮的功能

一氧化氮 (ＮＯ)是一种最新发现的、哺乳动物中最小、最轻并具有独特理化性质和生物学活性的信息和效应分子 ,能激活靶细胞中的鸟苷酸环化酶 (ＧＣ) ,提高环一磷酸鸟苷(ｃＧＭＰ)浓度 ,发挥一系列生物学作用 ,现已成为研究热点之一。ＮＯ广泛存在于神经系统、心血管系统、免疫系统、消化系统、生殖系统与呼吸系统等的细胞内 ,是传递神经信息、调节血压以及机构防御等一系列生命活动必不可少的生物信使。因此 ,内源性ＮＯ的生物学研究、ＮＯ在动物模型大鼠体内的分布及其功能的确定 ,将有助于在动物医学和人类临床医学领域进一步阐明机体某些…     

硒对镉所致鸡肝脏损害的保护效应

健康成年288商品(?)蛋鸡100只,随机分成5组,每组20只,各组基础日粮相同。Ⅰ组为对照组,其余各组在基础日粮中添加45ppm镉,其中Ⅱ、Ⅲ、Ⅳ组再分别添加5ppm、10ppm、15ppm硒作为保护组,Ⅴ组为镉中毒组。结果表明,镉中毒组鸡肝细胞肿大,呈明显脂肪变性伴发坏死,全血及肝脏GSH-Px和血清ChE活性显著降低(P<0.01),LDH总活性升高,LDH5>LDH4,肝脏镉含量与ChE呈负相关(r=-0.561 0,P<0.05),与(?)-GTP呈正相关(r=0.563 1,P<0.05)。保护组鸡的肝脏酶活性和病理形态学变化均较镉中毒组轻,10ppm硒能很好地保护45ppm镉对鸡肝脏的损害,其最适硒、镉摩尔浓度之比为1:3。     

芦丁对大鼠免疫器官指数的影响

研究天然植物提取物芦丁对大鼠免疫器官指数的影响,考察芦丁调节动物免疫功能的作用.选择16只Wistar雌性青春期大鼠,随机分为2组,每组8只,分别为对照组(每日每只灌胃生理盐水2 mL)、芦丁组(每日灌服芦丁60 mg/kg体重),正式试验为期2周.12只Wistar受孕母鼠,随机分为2组,每组6只,相同处理,从哺乳第...     

镉对大鼠肝细胞基因甲基化的影响

采用已建立的镉损伤肝细胞体外模型（4 μmol/L醋酸镉处理3 h）,通过偏重亚硫酸氢盐测序法和结合偏重亚硫酸氢盐的限制性酶切分析,研究镉对p53、MT和LINE1基因DNA甲基化的影响.结果显示,p53、MT和LINE1基因DNA甲基化均未受镉的影响.     

Effect of Cadmium on Lipid Peroxidation and on Some Antioxidants in the Liver,Kidneys and Testes of Rats Given Diet Containing Cadmium-polluted Radish Bulbs

The aim of this study was to examine the effects of cadmium (Cd), incorporated in radish bulbs, on malondialdehyde and glutathione levels and on superoxide dismutase activity in the liver, kidneys and testes of male rats. The control animals were given diet containing ordinary radish bulbs for 4, 8 and 12 weeks, while contaminated animals were given diet containing Cd-polluted radish bulbs (1.1 mg Cd/g of diet) for the same periods as in the controls. At each time point, rats were euthanized and the liver, kidneys and testes were removed. The results indicated that the body weight gain of contaminated rats was identical to that of the control rats. Cd concentrations in the liver, kidneys and testes increased significantly and gradually from the 4th to 12th week of treatment. Malondialdehyde concentrations decreased significantly in the liver and increased significantly in the kidneys and testes after 12 weeks of treatment, while glutathione levels increased significantly in the liver, and decreased significantly in the kidneys and testes at the same time. No changes were observed in SOD activity in the liver, while in the kidneys and testes, this activity was increased after 12 weeks of treatment as compared with the control rats.     

富硒植物对大鼠体内镉排泄的影响

对大鼠日粮添加富硒植物,以促进镉的排出。代谢试验结果证实,富硒玉米、茶叶、黄芪等植物,有较强地加快大鼠体内镉经粪便和尿液排泄的作用。饲料中添加上述几种富硒植物后,第１周内镉排泄总量占４周内排镉总量的５０％以上。４周内添加富硒玉米组大鼠粪镉排泄总量是对照组的２．３７～２．８８倍,茶叶组和黄芪组大鼠粪镉排泄总量分别是对照组大鼠的１．３９～１．４２和１．０５～１．２７倍。尿镉排泄的结果与此类似。富硒植物加入饲料后,尽管饲料中硒含量比亚硒酸钠组低,但促进大鼠体内镉排泄、减少镉在体内沉着的效果却更明显。     

氯甲基蛋氨酸对冷冻-束缚应激大鼠消化器官组织学结构的影响

为探讨氯甲基蛋氨酸对应激性胃溃疡的预防效果,制备了大鼠急性冷冻-束缚应激模型,通过观察冷冻-束缚应激所致大鼠消化系统器官的损伤性变化及氯甲基蛋氨酸对应激状态下大鼠消化器官组织结构的影响,判定氯甲基蛋氨酸对应激性胃溃疡的作用。结果表明,氯甲基蛋氨酸对大鼠冷冻-束缚应激性胃溃疡的消化系统器官具有明显的保护作用。     

硒对镉在鸡体内分布的影响

本试验按照在日粮中分别添加45ppm Cd、45ppm Cd 5ppm Se、45ppm Cd 10ppmSe、45ppm Cd 15ppm Se和仅饲喂基础日粮的处理方法,将成年蛋鸡100只分成5组,对各组鸡在试验40、60、90、120d不同时期肝、肾、心、肌肉组织硒、镉的含量进行了检测.结果表明,硒可降低镉在组织器官的蓄积,且在本试验条件下,随着日被硒水平的增加,其降低效果超明显;硒对镉损害的保护效应,主要取决于日粮中适宜的Sc/Cd摩尔比值,其最适Se/Cd摩尔比约为1:3.     

三硫钼酸钠对大鼠镉代谢的影响

补饲三硫钼酸钠,可以减少镉在生命器官内沉着,促进镉从粪、尿中排泄。在镉污染期,日粮中补饲硫钼酸钠,可使粪便镉排泄增多12.95％～33.66％,尿液镉排泄增多7.56％～21.66％,短期试验中显示增加更多。在粪中镉增多同时,钼浓度也增多,两者间呈正相关系（r=0.9596）。当停止镉污染以后,日粮中继续补饲I7ppm、10ppm、5ppm Mo的三硫钼酸钠,可使粪便镉排泄分别增加65.72％、10.18％和22.33％,尿液镉排泄分别增加109.17％、34.20％和50.36％,与未补钼的镉中毒大鼠相比,差异非常显著（P<0.01)。硫钼酸盐促进镉排泄的机理与它可使MT-Cd解离,使Cd转入分子量较大的蛋白质,因而有利于镉排泄有关。     

Effect of Cadmium in Feed on Organs and Meat Colour of Growing Pigs

One hundred and ninety-two barrows (Duroc × Landrace × Yorkshire, initial weight 27.7 kg) were used to investigate the effects of cadmium in feed on the function of selected organs and meat colour of growing pigs. The pigs were randomly allocatted into four different treatments. Each treatment included three replications with 16 pigs per replicate. The animals were fed corn–soybean basal diet and supplemented with 0, 0.5, 5.0, 10.0 mg/kg cadmium (as CdCl₂), respectively. The feeding trial ended when the average body weight of the pigs reach 90 kg. The results showed that, compared with controls, addition of 10 mg/kg cadmium to the diet resulted in significant elevations of relative weight of liver and spleen by 18.3% (p < 0.05) and 19.7% (p < 0.05) respectively, and of serum glutamic-pyruvic transaminase (GPT) and glutamic-oxaloacetic transaminase (GOT) activities by 17.8% (p < 0.05) and 27.4% (p < 0.05) respectively; and significant decreases of Na⁺/K⁺-ATPase activity in the liver by 24.6% (p < 0.05), the redness of longissimus dorsi by 26.6% (p < 0.05) and 24.9% (p < 0.05) at 0.75 h and 16 h post mortem, respectively, and of the myoglobin content of longissimus dorsi by 19.4% (p < 0.05). No changes were found in these indices above when the pigs were fed the diet supplied with 0.5 or 5 mg/kg cadmium (p > 0.05), nor in renal functions among cadmium-treatment treatments (p > 0.05) as indicated is the activities of urinary N-acetyl-β-d-glucosaminidase (NAG) and alkaline phosphatase (ALP) and the content of urinary protein. The study indicated the adverse effects of 10 mg/kg cadmium in feed on liver functions and meat colour of growing pigs.     

Fas对镉暴露致大鼠大脑皮质自噬体形成的影响

为探究死亡受体Fas在镉暴露致大鼠大脑皮质自噬体形成中的作用,将24只21日龄雄性SD大鼠随机分为4组,分别为对照组、镉组、镉与对照病毒共处理组、镉与Fas基因沉默病毒共处理组。试验期间,对照组大鼠自由饮用纯净水,病毒处理组大鼠于第1天以每只1.4×10¹¹vg的剂量通过尾静脉注射相应病毒,4周后镉染毒组大鼠自由饮用镉水(50 mg·L^-1),持续90 d。试验结束后,透射电镜观察大脑皮质中自噬体数量,Western blot检测大脑皮质细胞外信号调节激酶1/2(Erk1/2)、p-Erk1/2、自噬相关蛋白7(ATG7)、自噬相关基因(Beclin-1)、微管相关蛋白1轻链3(LC3)蛋白表达水平,免疫荧光染色检测LC3表达水平。结果显示,镉暴露增加大脑皮质中自噬体数量,极显著激活Erk1/2并上调ATG7、Beclin-1、LC3蛋白表达水平(P<0.01);Fas基因沉默抑制镉引起的自噬体数量增加,极显著抑制镉致Erk1/2激活及ATG7、Beclin-1、LC3蛋白表达水平升高(P<0.01)。结果表明,Fas通过激活Erk1/2参与镉致大鼠大脑皮质自噬体形成。     

口服不同剂量胆碱在肉鸡血液中的代谢动力学研究

本试验旨在采用药代动力学的研究手段,探索胆碱在肉鸡血液中的吸收代谢规律。选用12只9周龄的爱拔益加(AA)肉公鸡,随机分为3组,每组4只鸡,按体重分别单次口服氯化胆碱200和400 mg/kg(以胆碱计算),并设空白对照组。采取血样,对血样中的胆碱浓度进行离子色谱法的测定,并用药代动力学处理软件Win Nonlin 5.2采用非房室模型计算药代动力学参数。结果显示,空白对照组内源胆碱的合成水平基本稳定;不同给药剂量的氯化胆碱在肉鸡血液中的药代动力学过程存在差异,表观分布容积(Vz/F)和血药表观清除率(CL/F)差异极显著(P0.01);给药剂量在200~400 mg/kg,胆碱的药代动力学行为呈线性关系。肉鸡口服2种剂量的主要药代动力学参数如下。200 mg剂量组:达峰时间(Tm ax)为8.0 h,达峰浓度(Cm ax)为399.88 mg/kg,半衰期(t1/2)为7.60 h,血浆浓度第一时间曲线下面积(AUMC)为5 979.06 mg/(kg·h),Vz/F为876.99 L/kg,CL/F为83.27 mg/(kg·h);400 mg剂量组:Tm ax为8.0 h,Cm ax为445.88 mg/kg,t1/2为9.91 h,AUMC为10 899.78 mg/(kg·h),Vz/F为318.43 L/kg,CL/F为21.22 mg/(kg·h)。200 mg剂量的胆碱更易入胞用于物质的生物合成。以上结果提示,单纯依靠增加氯化胆碱剂量无法实现提高胆碱生物利用率的目的。     

Effect of the Oral Formalin and Fauna-free on the Microbiocoenosis and Activities of Digestive Enzymes in the Rumen of Sheep

6 Small-tail Han sheep ram,2 to 3 year's old,with body weight of 48.3 kg±5.6 kg,were fitted with permanent rumen fistula and fed with the diet containing 70% of corn stalk.The experiment was designed as 4×4 Latin square,the sheep were orally administered with formalin at 0 mL/kg diet (control,treatment 1),1.0 mL/kg diet (low dose,treatment 2),3.0 mL/kg diet (high dose,treatment 3) and completely fauna-free (treatment 4),to study the effects of various treatments on the rumen microbiocoenosis,activities of digestive enzymes,NH₃-N and VFAs in rumen fluid of sheep,and their correlation with voluntary intake.The results showed that,compared with control,the voluntary intakes of dry matter in treatments 1,2 and 3 were increased by 14.9% (P<0.01),-6.8% (P>0.05) and -16.5%(P<0.01),respectively;NH₃-N were decreased by 10.5% (P<0.05),13.0% (P<0.05) and 23.0%(P<0.01),respectively;The protozoa number in rumen fluid were decreased by 59.3%,93.2% and 100.0%(P<0.01),respectively;The total number of bacteria were increased by 41.1%,-8.2% and 84.5%(P<0.01),respectively;The fungi copies were increased by 16.5%(P>0.01),23.5% (P<0.05) and 38.1%(P<0.01),respectively;The activities of endocellulase in treatments 1,2 and 3 were increased by 22.6%,-14.6% and -27.5%(P<0.01),respectively;The activities of exocellulase were increased by 15.5%,-23.9% and -25.2%(P<0.01),respectively;The activities of cellobiose were increased by 20.0%,-25.7% and -26.2%(P<0.01),respectively;The activities of xylanase were decreased by 0.4%(P<0.05),0.5%(P<0.05) and 0.1% (P>0.05),respectively;The activities of pectinase were decreased by 12.0%,11.0% and 2.8%(P<0.01),respectively;The activities of amylase were increased by 12.2%,15.3% and 19.9%(P<0.01),respectively;The activities of protease were decreased by 22.1%,48.0% and 22.2%(P<0.01),respectively.The correlation coefficients (R²) of the activities of the endocellulase,exocellulase and cellobiose with voluntary intake of sheep were 0.994,0.897 and 0.901.It was concluded that when the low dose of formalin was orally administrated the voluntary intake of sheep was increased,whereas the high dose of formalin or fauna-free was decreased;The factors determined the voluntary intake of sheep were the activities of endocellulase,exocellulase and cellobiose,rather than the numbers of the protozoa,bacteria or fungi,or the activities of other digestive enzymes in rumen fluid.