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331.
鸡亚慢性镉中毒后肝脏镉含量的测定与形态学观察 总被引:1,自引:0,他引:1
【目的】探讨亚慢性镉中毒鸡肝脏中镉的蓄积情况及显微和超微结构的变化。【方法】将30只50日龄健康海蓝白蛋鸡随机分为3组,对照组饲喂基础日粮,低镉组饲喂基础饲粮+CdCl2140mg/kg,高镉组饲喂基础饲粮+CdCl2210mg/kg,分别在20d、40d、60d取肝脏测定镉含量,并做光镜和电镜观察。【结果】镉在肝中的蓄积量存在时间和剂量效应。加镉组鸡肝细胞发生变性、坏死,细胞内线粒体、内质网等膜性细胞器损害严重。【结论】肝脏是镉重要的靶器官;随着染镉剂量的增加和时间的延长,肝脏的损害越严重。 相似文献
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AIM: To investigate the protective effects of human acidic fibroblast growth factor (aFGF) on hypothermic preservation of rat liver. METHODS: Twenty-four Wistar rats were randomly divided into 2 groups (n=6): hypertonic citrate adenine (HCA) solution control group and experimental group (aFGF compound solution, containing 40 μg/L aFG14-154 in HCA solution). The isolated livers were preserved in corresponding solution for 12 h or 24 h, and the content of malondialdehyde (MDA), the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and the changes of liver weight in the 2 groups were analyzed. The histopathological changes of the livers were also examined. RESULTS: Compared with HCA control group, the levels of ALT, AST and MDA and the changes of liver weight were significantly decreased in experimental group (24 h), and the changes of liver histopathology were obviously alleviated in experiment group. CONCLUSION: aFGF can reduce rat hepatic injury. The protective effects of aFGF may be related to attenuating cell swelling and improving the capacity of anti-oxidative damage in the liver. 相似文献
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AIM:To investigate whether hepatocyte apoptosis is contributed to liver ischemia-reperfusion (I/R) injury and the relationship between liver caspase-3 activity and hepatocyte apoptosis in cirrhotic rats. METHODS:Liver ischemia-reperfusion is induced by Pringle maneuver. The cirrhotic rats were randomized into two groups: Group A: simple hepatic blood inflow occlusion (HBIO); Group B: HBIO + inhibitor, before HBIO, ZVAD-fmk 15 mg/kg was injected via dorsal penis vein; Group C: healthy rat, simple HBIO. The ischemia time was 30 min in these groups. Serum aspartate aminotransferase(AST), liver caspase-3 activity, and apoptotic hepatocytes were examined in the three groups. RESULTS: After 6 h of reperfusion, the liver caspase-3 activity was markedly elevated and reached its peak, which was statistically higher than that of before I/R . The same change occurred in hepatocyte apoptosis between 6 h of reperfusion and before I/R (20.9%±4.9% vs 0.5%±0.3%, P<0.01). As the reperfusion prolonged, the caspase-3 activity and apoptotic hepatocyte decreased gradually. The 7th-day survival rate was 62.5% in group A. The serum AST, liver caspase-3 activity and apoptotic hepatocytes were significantly higher in group A than those in group B and C, representing the most severe liver injury among the three groups. CONCLUSION:Hepatocyte apoptosis is the major form of cell death in liver ischemia-reperfusion injury in cirrhotic rats. Hepatoctye apoptosis induced by I/R is caspase-3 dependent, and inhibiting caspase-3 can alleviate liver injury. The caspase-3 dependent hepatocyte apoptosis is highly contributed to the pathological phenomenon that the ischemic sensitivity of cirrhotic liver is higher than normal liver. 相似文献
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Miao Zhang Lingxiang Xin Endong Bao Jrg Hartung Zhenhua Yue 《Research in veterinary science》2011,90(3):432-438
Twenty pigs were randomly divided into four groups of five pigs each (not transported – control, 1, 2 and 4 h of transportation). A significant increase of ALT, AST and CK in the blood serum and acute parenchyma cell lesions were observed and those were characterized by acute degenerations in the heart and liver. Hsp27 expression levels increased significantly in the heart after 2 h and in the liver after 4 h of transportation, accompanying with the hsp27 mRNA increasing significantly in the heart and liver after 1 h of transportation. αB-crystallin expression levels were fluctuant (not significantly) in the heart and liver during transporting, however, αB-crystallin mRNA increase notably in the heart after 1 h and decrease significantly in the liver at 1 and 2 h of transportation, respectively. In conclusion, the cellular damage to the heart and liver is highest after 1 h of transportation, Hsp27 and αB-crystallin play dissimilar roles and show tissue-specific response in different tissues during transportation. 相似文献
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Dietrich Pizzigatti Fernando Arévalo Batista Charles Ferreira Martins Olímpio Crisóstomo Ribeiro Marcelo Monteiro Nunes Thiago Rinaldi Müller 《Journal of Equine Veterinary Science》2011,31(1):3-7
Both cholangiocarcinoma and squamous cell carcinoma of the stomach stratified squamous epithelial portion are rarely found in equine medicine despite being more common in human beings, dogs, and cats. The objective of the present article was to report the simultaneous occurrences of these two types of neoplasias in an 11-year-old mare. Numerous firm, whitish nodules were distributed throughout the liver parenchyma and those protruding over its surface were umbilicated in their appearance. It was verified that the nodules adhered to the peritoneum and omentum, diaphragm, spleen, and stomach serosa compressed the adjacent structures. The stomach stratified squamous epithelial portion, particularly originating in the margo plicatus toward the cardia, was covered by numerous smooth, whitish spherules. Microscopic examination allowed the liver, tumor, and the abdominal implants to be identified as a cholangiocarcinoma, and the stomach neoplasia as a carcinoma of its stratified squamous epithelial portion. Considering this as an uncommon finding, although when considered individually, the presence of a cholangiocarcinoma and a squamous cell carcinoma of the stratified squamous epithelial portion of the equine stomach in the same specimen is worthy of reporting. 相似文献
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AIM: To observe the changes of endoplasmic reticulum and the biomarker of endoplasmic retidum stress (ERS), glucose-regulated protein 78(GRP78),in the process of liver fibrosis induced by carbon tetrachloride (CCl4). METHODS: Male Wistar rats weighing 180 g to 220 g were divided into control group and liver fibrosis group. The rats in liver fibrosis group were induced by hypodermic injection of CCl4 for 4 weeks or 8 weeks. The liver index and the serumactivity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were analyzed. The liver fibrosis and the morphological changes of endoplasmic reticulum were observed under light and electronic microscopes, respectively. Additionally, the expression of GRP78 at mRNA and protein levels was determined by real-time PCR and the method of immunohistochemistry, respectively. RESULTS: The liver index, serum ALT and AST activity in liver fibrosis group were obviously higher than those in control group. Swelling and reduced number of endoplasmic reticulum were observed in the hepatocytes of fibrotic rats compare to the controls. The levels of GRP78 protein and GRP78 mRNA in the liver of hepatic fibrotic rats were obviously higher than those in the control rats. CONCLUSION: In the process of liver fibrosis induced by CCl4, the obvious morphological changes of endoplasmic reticulum and increased expression of ERS protein indicate that ERS plays an important role in the liver fibrosis. 相似文献