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401.
AIM: To investigate the adaptive characteristics of mitochondria in plateau pikas at different altitudes. METHODS: According to the altitudes of the capture area, plateau pikas were divided into 4 300 m group (Mado Star Sea, n=6) and 2 900 m group (Laoji Mountain South, n=6). The red blood cells and hemoglobin of the animals in 2 groups were measured. The levels of mitochondrial oxidative phosphorylation (OXPHOS) and fatty acid oxidation (FAO) in the liver and skeletal muscle, and mitochondrial H2O2 production level in the skeletal muscle were determined by high-resolution mitochondrial respirometer. RESULTS: The hemoglobin of the plateau pika in 4 300 m group was significantly lower than those in 2 900 m group. The liver state 4 respiration rate of mitochondrial respiratory chain complex I (CI-LEAK), mitochondrial respiratory chain complex I state 3 respiration rate (CI-OXPHOS) and respiratory chain complex I+Ⅱ state 3 respiration rate(CI+Ⅱ-OXPHOS), electron transfer capacity of respiratory chain complex I+Ⅱ (CI+Ⅱ-ETS), the electron transport capacity of the respiratory chain complex Ⅱ (CⅡ-ETS) in 2 900 m group were increased, and the coupling efficiency was decreased compared with 4 300 m group (P<0.05). The skeletal muscle CI-LEAK,CI+Ⅱ-OXPHOS and CI+Ⅱ-ETS were higher than those in 4 300 m group. Mitochondrial state 4 respiration rate with palmitic acid carnitine and malate as substrates (FAO-LEAK) of liver and skeletal muscle in 2 900 m group were increased compared with 4 300 m group. The skeletal muscle with palmitic acid carnitine as a substrate for fatty acid metabolism state 3 respiratory rate (FAO-OXPHOS) was increased in 2 900 m group compared with 4 300 m group. The H2O2/O2 flow ratio (ΔH2O2) in 2 900 m group was lower in state 4 respiration rate of mitochondrial respiratory chain complex I (LEAK), state 3 of mitochondrial respiratory chain complex I (OXPHOS), state 3 of mitochondrial respiratory chain complex I+Ⅱ (OXPHOS*) and electron transfer capacity of respiratory chain complex I+Ⅱ (ETS) than 4 300 m group. CONCLUSION: Plateau pikas with different altitudes have different mitochondrial adaptation characteristics.  相似文献   
402.
AIM:To investigate the effect of urantide on the liver function and histomorphology in the rats with atherosclerosis (AS).METHODS:The AS Wistar rat model was induced by intraperitoneal injection of vitamin D3 (VD3) and feeding with high-fat diet. The rats were randomly divided into normal control group, AS model group, positive medicine group and urantide group. The liver function indexes of the rats were measured by biochemical test, and the pathological changes of the aorta and liver of the rats were observed by hematoxylin-eosin (HE) staining. The mRNA expression of urotensin Ⅱ (UⅡ) and GPR14 at mRNA and protein levels in rat livers was determined by RT-qPCR and Western blot. RESULTS:The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltransferase (γ-GT), lactate dehydrogenase (LDH), total bilirubin (TBIL), indirect bilirubin (IBIL) and alkaline phosphatase (ALP) in AS model group were significantly increased compared with normal control group (P<0.05). The above indexes in urantide group were remarkably decreased compared with AS model group (P<0.05). No change of the levels of direct bilirubin (DBIL), total protein (TP), globulin (GLB) and albumin (ALB) in each group was observed. Urantide postponed hepatocyte fatty degeneration and repaired hepatocyte injury in the AS rats. Compared with normal control group, the mRNA and protein levels of UⅡ and GPR14 in the liver were significantly increased in AS model group (P<0.05). With the prolongation of dosing time, the mRNA and protein levels of UⅡ and GPR14 in the liver were significantly decreased in urantide group compared with AS model group (P<0.05). CONCLUSION:Urantide significantly attenuates the liver damage caused by liver fatty degeneration in AS rats.  相似文献   
403.
以Abor Acres商品代肉用仔鸡为对象,进行了两次不同维生素A水平饲养效果试验。第一次试验用1,600只一日龄混合雏,分五个维生素A添加量。结果表明:每千克饲粮添加750 IU微生素A醋酸酯的鸡,49日龄增重显著低于12,000IU组;添加1500 IU、4000 IU、8000 IU三个中间水平鸡的增重与750和12000 IU没有显著差异。第二次试验用576只一日龄混合雏,检测了添加20,000 IU和1,500 IU两种维生素A水平的效果,结果发现每千克饲粮添加20,000IU维生素A醋酸酯的增重显著低于1,500IU组。高水平组鸡的血浆、肝脏维生索E含量分别比低水平组低6和10倍。  相似文献   
404.
用三水平棉籽饼、菜籽饼的饲粮饲喂蛋鸡300d,结果表明,各组饲料配方对鸡肝中7种微量元素含量的影响无显著差异;三水平棉籽饼对鸡肝锰有显著影响,低、中、高水平肝锰分别为5.97ppm,5.85ppm,8.05 PPm;三水平菜籽饼对肝硒有显著影响,低、中、高水平肝硒分别为0.708PPm,0.696ppm,0.792ppm,SGOT与肝铁之间呈强正相关(r=0.7206)。  相似文献   
405.
本文通过对肉仔鸡肝脏生化指标的测定及组织结构的观察,旨在研究葡甘露聚糖对黄曲霉毒素B1(AFB1)的吸附效果。选用8日龄、180只体重相近的肉仔鸡随机分成3组,分别为基础日粮组、基础日粮 0.1mg/kgAFB1组和基础日粮 0.1mg/kgAFB1 0.1%葡甘露聚糖组,试验期21d。试验结果表明:(1)基础日粮中加入0.1mg/kgAFB1,导致肝脏组织中琥珀酸脱氢酶活性和胆碱酯酶活性显著降低(P<0.05);碱性磷酸酶活性显著升高(P<0.05);γ-L-谷氨酰转肽酶活性升高,第21、28日龄时达到显著差异(P<0.05);抗氧化指标谷胱甘肽过氧化物酶、超氧化物歧化酶活性降低,脂质过氧化产物丙二醛含量升高,且均在第21、28日龄时达到显著差异(P<0.05);肝脏组织切片观察到肝细胞广泛性坏死,胆管异常增生;(2)0.1mg/kgAFB1日粮中加入0.1%的葡甘露聚糖,上述指标均与对照组无显著差异(P>0.05),组织切片未见上述病理现象。结果显示,葡甘露聚糖减轻或基本消除了黄曲霉毒素对肝脏的损伤。  相似文献   
406.
AIM: To observe the changes of endoplasmic reticulum stress-related molecules CCAAT/enhancer-binding protein homologous protein(CHOP) and Tribbles homolog 3(TRB3) in the process of liver fibrosis induced by carbon tetrachloride (CCl4). METHODS: Male Wistar rats weighing 180 g to 200 g were divided into 4-week normal control group, 8-week normal control group, 4-week liver fibrosis group and 8-week liver fibrosis group. The rats in liver fibrosis groups were induced by subcutaneous injection of 40% CCl4 for 4 weeks or 8 weeks. The pathological changes of the liver were observed under light microscope. The protein level of ATF6 was determined by Western blotting. The protein and mRNA levels of CHOP and TRB3 in the liver were analyzed by immunohistochemistry, Western blotting and real-time PCR, respectively. The apoptosis of hepatocytes was measured by TUNEL assay. RESULTS: Pseudolobuli formed in the liver tissue of hepatic fibrotic rats. Compared with the control rats, the protein level of p90ATF6 was obviously decreased, the protein level of p50ATF6 was obviously increased, and the protein and mRNA levels of CHOP and TRB3 were obviously higher in the hepatocytes of hepatic fibrotic rats. The apoptosis of hepatocytes was also increased in 4-week and 8-week fibrosis groups. CONCLUSION: In the process of liver fibrosis induced by 40% CCl4, the obviously increased expression of endoplasmic reticulum stress-related molecules CHOP and TRB3 at protein and mRNA levels indicates that endoplasmic reticulum stress may play an important role in the liver fibrosis by promoting the apoptosis of hepatocytes.  相似文献   
407.
AIM To study the effect of mouse circular RNA-42398 (mmu_circ_42398) over-expression on the activation of hepatic stellate cells. METHODS Mouse hepatic stellate JS1 cells were cultured and randomly divided into control group, vector group and mmu_circ_42398 over-expression group.mmu_circ_42398 over-expression plasmid vector was constructed, and then transiently transfected into JS1 cells using Lipofectamine 2000. The cells were collected 48 h after transfection. Expression of mmu_circ_42398 was detected by RT-qPCR.The backsplice site of PCR products was verified by sequencing. The protein levels of α-smooth muscle actin (α-SMA), collagen type I (Col I), transforming growth factor β1(TGF-β1), Smad2, Smad3, p-Smad2 and p-Smad3 in the cells were determined by Western blot. RESULTS RT-qPCR results showed that the expression of mmu_circ_42398 was significantly increased after mmu_circ_42398 over-expression vector was transiently transfected into the JS1 cells (P<0.01). The protein expression levels of α-SMA and Col I were significantly decreased(P<0.01), and the phosphorylation levels of Smad2 and Smad3 were decreased significantly in mmu_circ_42398 over expression group (P<0.01). However, the protein expression levels of TGF-β1, Smad2 and Smad3 had no significant change (P>0.05). CONCLUSION mmu-circ-42398 inhibits the activation of hepatic stellate cells via TGF-β1/Smads signaling pathway modulation.  相似文献   
408.
A simulate daily oriental dietary pattern (a blend of lard and soybean oil) was performed in this research to investigate influence on liver and kidney function. Sixty mice were randomly divided into 6 groups with diets of different fat added oils respectively for 12 weeks. Malondialdehyde and uric acid contents in mice fed with blended oil were significantly lower than in those fed only with soybean oil and lard due to the improved activities of antioxidant enzymes. Daily use of a blend of lard with soybean oil significantly increased antioxidant capacity, reduced lipid peroxidation of liver and serum uric acid production, thus protected liver and renal function. It also suggests that the oriental dietary pattern might reduce the risk of gout.  相似文献   
409.
410.
为研究钼对鸡肝肾组织形态学的影响,选取80只健康2w龄雏公鸡,随机分为5组,每组16只。通过在饮水中添加不同剂量的钼酸钠(以钼离子计),建立试验动物模型:对照组(钼:0mg.L-1)、钼Ⅰ组(钼:12.5mg.L-1)、钼Ⅱ组(钼:25.0mg.L-1)、钼Ⅲ组(钼:50.0mg.L-1)、钼Ⅳ组(钼:100.0mg.L-1)。分别在试验处理第10w,采集鸡的肝脏和肾脏,固定包埋处理后,制得切片,经HE染色分析,用显微镜观察鸡肝肾组织形态学变化。肾脏和肝脏的组织形态学观测结果显示:加钼的各组与对照组相比,细胞数量增多,且有浓染,出现坏死现象,细胞核皱缩加剧,有少量充血。试验低剂量(钼Ⅰ组、钼Ⅱ组)下的钼导致鸡肝肾组织发生不明显的病理形态学变化,而高剂量组(钼Ⅲ组、钼Ⅳ组)发生明显的病理形态学变化。  相似文献   
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