Sexual dimorphism in LEC rat liver: suppression of carbonic anhydrase III by copper accumulation during hepatocarcinogenesis

We examined age-related changes in the protein expression of carbonic anhydrase III (CAIII) in livers of Long-Evans with a cinnamon-like color (LEC) rats using an agouti color (LEA) rats as controls. The levels of the protein of CAIII in the liver of LEC male rats increased before 20 weeks of age, at the stage of acute hepatitis, and were decreased at 54 weeks of age, while those of CAIII in the liver of LEA male rats were highly expressed at all ages. In the normal LEA rats, CAIII showed sexual dimorphism. The level of CAIII in LEA male rat liver relative to female was four times higher. On the other hand, young LEC rat (at 4-12 weeks) showed a higher protein level of CAIII than LEA rats, and then decreased during development of hepatitis. CAIII mRNA also decreased in the LEC rat liver during hepatocarcinogenesis. The level of CAIII in the tumor region was lower than that in the tumor-free region. Immunohistochemical analysis showed that glutathione S-transferase P (GST-P) was positive and CAIII was negative in the precancerous region. The expression of CAIII was suppressed in cancerous lesions in hepatoma-bearing LEC rat liver compared to uninvolved surrounding tissues. These results indicated that suppression of CAIII accompanied hepatocarcinogenesis and it is a secondary consequence of the high copper levels in the liver.     

The LEC rat: a model for human hepatitis, liver cancer, and much more.

The LEC rat is an inbred mutant strain with spontaneous hepatitis isolated from Long-Evans rats. Since approximately 40% of LEC rats die of fulminant hepatitis, the rat serves an animal model for studying the pathogenesis and treatment of human fulminant hepatitis. The remaining 60% of LEC rats survive and develop chronic (prolonged) hepatitis and subsequently develop liver cancer. Therefore, the LEC rat serves an important animal model for studying the significance of chronic hepatitis in the development of human liver cancer, which often develops in association with chronic hepatitis. The LEC rat can also be used as an animal model of Wilson's disease, since recent studies have disclosed high copper accumulation in the liver and low ceruloplasmin concentration in the serum of this mutant rat.     

Increased polyploid incidence is associated with abnormal copper accumulation in the liver of LEC mutant rat

Long-Evans Cinnamon (LEC) rats are deleted at the p-type copper transport ATPase gene (Atp7b), so that they exhibit abnormal hepatic copper concentration. In this study, it was confirmed that LEC rat liver possesses a feature of increase in polyploid. Furthermore, a segregation analysis using backcrosses between LEC and F344 normal rats showed that the increased polyploid incidence is strongly associated with excessive copper content in their liver. These results should demonstrate that copper cytotoxicity leads to the impairment of mitotic progression, resulting in the increase of polyploid in the liver of LEC rats.     

Ferrous and ferric iron accumulates in the brain of aged Long-Evans Cinnamon rats, an animal model of Wilson's disease

The Long-Evans Cinnamon (LEC) rat, which accumulates excess copper (Cu) in its liver, is an animal model of Wilson's disease. We evaluated and compared the distributions of Cu, ferrous (Fe2+), and ferric (Fe3+) iron in four-brain regions, namely, in the cerebral cortex, cerebellum, substantia nigra (SN), and striatum of LEC and Long-Evans Agouti rats at 30 and 55 weeks. Cu levels were elevated in the striatum of LEC rats, and Fe2+ and Fe3+ were higher in the striatum and SN of LEC rats. Ratios of Fe2+ to Fe3+ were > 1 in four regions, and were highest in the striatum and SN of LEC rats. Cu and iron levels were found to be augmented during aging, and we suggest that these accumulations may exert deleterious effects in aged LEC rats. This study is the first report that demonstrates regional differences of Fe2+ and Fe3+ accumulation in the brain of aged LEC rats. Further studies are required to elucidate the mechanisms of Cu and iron accumulations and of their effects.     

Contribution of Va24Vb11 natural killer T cells in Wilsonian hepatitis

Wilson disease (WD) is an autosomal recessive disorder of copper transport, resulting in copper accumulation and toxicity to the liver and brain. There is no evidence that the WD patient's immune system attacks copper accumulated hepatocytes. Here we describe that the frequency and absolute number of Valpha24+Vbeta11+ natural killer T (NKT) cells were significantly increased in 3 cases of WD, whereas those of CD3+CD161+ NKT cells were within the normal range. Patients no. 1 and 2 had a presymptomatic form of WD. Their tissue specimens showed pathological changes of mild degeneration of hepatocytes with a few infiltrating mononuclear cells and a low degree of fatty change. Patient no. 3 displayed fulminant hepatitis with Coombs-negative haemolytic anaemia. The tissue specimens of patient no. 3 showed macronodular cirrhosis with thick fibrosis, inflammatory infiltrates and spotty necrosis. Human Valpha24+Vbeta11+ NKT cells are almost equal to CD1d-restricted NKT cells. Therefore we investigated CD1d-restricted NKT cells in the LEC rat as an animal model of WD. In LEC rats before hepatitis onset, the number and phenotype of liver NKT cells were normal. At about 4 months of age all LEC rats developed acute hepatitis accompanied by acute jaundice, and CD161high NKT cells developed in their livers. CD161highalphabetaTCRbright NKT cells developed in some of them. Their hepatitis was severe. CD161highalphabetaTCRbright NKT cells expressed an invariant rat Valpha14-Jalpha281 chain, which is CD1d-restricted. Furthermore, liver lymphocytes in the acute jaundiced LEC rats with CD161highalphabetaTCRbright NKT cells had significant and CD1d-specific cytotoxic activity.     

Macrophage populations and apoptotic cells in the liver before spontaneous hepatitis in Long-Evans Cinnamon (LEC) rats

The inbred mutant strains of Long-Evans Cinnamon (LEC) rats spontaneously develops acute hepatitis as a result of abnormal copper accumulation, followed by chronic hepatitis, cholangiofibrosis and hepatocellular carcinoma. To shed some light on the role of macrophages in the liver failure, immunohistochemical methods were used to investigate the kinetics of macrophage populations in the liver of male LEC rats, in relation to the appearance of myofibroblastic cells and hepatocyte apoptosis. Rats examined at 24 weeks of age and moribund rats killed at 22-25 weeks of age had increased serum concentrations of aspartate aminotransferase and alanine aminotransferase, with jaundice and histological changes indicative of hepatic failure, whereas rats examined at 8, 12, 16 or 20 weeks old showed no such abnormal findings. Immunolabelling with ED1 (a monoclonal antibody recognizing rat macrophages) and ED2 (a monoclonal antibody specific for rat resident macrophages) revealed that numbers of blood monocyte-derived macrophages and Kupffer cells began to increase markedly at 16 weeks of age (before the onset of hepatitis). However, alpha-smooth muscle actin (SMA)-positive myofibroblastic cells (modulated perisinusoidal cells) and hepatocyte apoptosis, demonstrable by the TUNEL method, were rarely seen at 8, 12, 16, 20 or 24 weeks. There was no close relationship between macrophage expansion and the appearance of myofibroblastic cells or hepatocyte apoptosis. In moribund rats, only a few SMA-positive cells were seen in the periportal zones; hepatocytes undergoing apoptosis increased in number, and macrophages engulfing apoptotic bodies were observed occasionally, suggesting that apoptosis was related to hepatic failure as an early event. In addition, immunohistochemical examination demonstrated abnormal deposits of laminin along the sinusoids from 20 weeks, as an initial extracellular matrix protein in LEC rat livers.     

Bone marrow-derived progenitor T cells convey the origin of maturational arrest from CD4+CD8+ to CD4-CD8+ thymocytes in LEC mutant rats.

A mutant strain of rats, LEC, shows a novel arrest of T cell maturation from CD4+CD8+ to CD4+CD8- but not to CD4-CD8+ cells in the thymus. Transplantation of LEC rat fetal thymuses into the subcapsule of the kidney of athymic nude rats resulted in a normal maturation of thymocytes in the thymus graft. Furthermore, both single-positive thymocytes and peripheral lymph node T cells expressed T cell receptor alpha/beta antigen, and lymph node T cells acquired the ability to produce interleukin 2 upon mitogen stimulation. Transplantation of fetal thymuses from LEA rats, which express the same major histocompatibility complex haplotype as LEC rats, into LEC rat kidney subcapsule resulted in the maturational arrest from CD4+CD8+ to CD4+CD8- cells in the thymus graft. These data strongly suggest that bone marrow-derived progenitor T cells carry the cause of maturational arrest and that the thymic stroma of LEC rats has a normal potential to nurse thymocytes.     

Comparing serum and hepatic concentrations of iron, copper, and cobalt in healthy sheep and sheep with chronic fasciolosis

Fasciolosis is one of the most important parasitic diseases of ruminants. This parasite causes liver dysfunction which may contribute to albumin synthesis and copper transferring to the liver and also reduces the elemental storage. Due to these reasons and to determine the effects of fasciolosis on serum and liver iron, copper, and cobalt status, the present study was conducted on 460 slaughtered sheep. During antemortem examination and after giving an identification number, blood samples were taken, and age, sex, and origin of animals were recorded. Visual inspection and palpation were performed on the liver to determine Fasciola infestation; then, liver samples were taken from 100 sheep (50 infested and 50 healthy ones), and the concentration of the mentioned minerals was measured by atomic absorption spectrophotometry. The results indicated that liver iron, copper, and cobalt concentrations in healthy sheep (74.47, 32.95, and 0.13 ppm, respectively) were significantly higher than those in sheep with fasciolosis (36.78, 11.22, and 0.05 ppm, respectively) (P?<?0.05). These findings may explain the role of hepatic injuries caused by fasciolosis on mineral status and also the role of minerals on parasite persistency.     

Urantide对动脉粥样硬化大鼠肝功能及组织形态学的影响

目的:探讨urantide对动脉粥样硬化(AS)大鼠肝功能及组织形态学的影响。方法:采用腹腔注射维生素D3(VD3)及高脂饮食的方法复制Wistar大鼠AS模型,随机分为正常对照组、AS模型组、阳性药组和uran-tide组。生化分析仪检测各组大鼠肝功能指标;HE染色观察大鼠胸主动脉和肝脏的病理学变化;RT-qPCR和Western blot法检测大鼠肝脏中尾加压素Ⅱ(UII)及其受体GPR14的mRNA和蛋白表达水平。结果:AS模型组大鼠血清中丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、γ-谷氨酰转移酶(γ-GT)、乳酸脱氢酶(LDH)、总胆红素(TBIL)、间接胆红素(IBIL)和碱性磷酸酶(ALP)水平较正常对照组显著升高(P 0.05);urantide组大鼠上述各项指标较模型组均显著降低(P 0.05);各组血清中直接胆红素(DBIL)、总蛋白(TP)、球蛋白(GLB)和白蛋白(ALB)水平均无显著变化。Urantide可延缓AS大鼠肝细胞脂肪变性,修复肝细胞损伤。AS组大鼠肝脏中UII和GPR14mRNA及蛋白表达水平均较正常组显著增高(P 0.05);随着给药时间的延长,urantide治疗组大鼠肝脏中UII和GPR14 mRNA及蛋白表达水平较AS模型组显著降低(P 0.05)。结论:Urantide可明显减轻AS大鼠肝脂肪变性所引起的肝功能损伤。     

生物陶瓷宫内节育器的应用与安全性

BACKGROUND: Intrauterine device (IUD), widely used for contraception, achieves contraceptive effect by mechanical stimulation or chemical interference. Biological ceramics have been reported to have good performance and biocompatibility, but its effect used for IUD is rarely reported. OBJECTIVE: To explore the contraceptive effect of biological ceramic IUDS. METHODS: Totally 90 female rats were randomly divided into three groups (n=30 per group). The biological ceramic IUD and the bare copper IUD were respectively implanted into the middle of rat uterus, and blank control group received no intervention. One month later, according to the male and female ratio of 3:1, 30 male rats were selected to mate with female rats in the three groups. At 14 days after mating, 10 female rats were randomly selected from each group to detect the number of embryos in the implanted side and the number of pregnant rats, and the contraceptive rate was calculated. Ten rats among the remaining rats in each group underwent removal surgery of IUD, and mated with male rats again. After 60 days, the remaining rats were sacrificed to observe the morphology of liver, kidney and uterus. RESULTS AND CONCLUSION: The number of uterine embryos and pregnant rats in the groups of biological ceramic and bare copper IUD was significantly lower than that in the blank control group (P < 0.05), and the contraceptive rate reached 100% in the former two groups. The number of uterine embryos of implanted side and pregnant rats, and fertility recovery rate in the blank control and biological ceramic IUD groups were significantly higher than those in the bare copper IUD group (P < 0.05), but no significant differences were found between blank control and biological ceramic groups (P > 0.05). In the biological ceramic IUD group, there existed mild gland expansion, and visible some neutrophils both inside and outside the uterine cavity, but these phenomena were milder compared with the bare copper IUD group. No abnormal changes occurred in the rat kidney and liver. These results show that the biological ceramic IUD and bare copper IUD both can obtain the ideal contraceptive effect but make no damage to the rat kidney and liver. Especially, biological ceramic IUD holds better reversible recovery of fertility ability with less endometrial stimulation.     

急、慢性铁负载大鼠黑质内铁及TH样阳性细胞变化的相伴关系

许多研究证实Parkinson病(PD)患者黑质内铁含量显著增高,并伴有铁代谢的改变,由于铁的细胞毒作用和它能够促进羟自由基产生的能力,使其在PD中的作用不容忽视。本实验用葡聚糖铁建立急慢性铁负载模型大鼠,采用酪氨酸羟化酶(TH)免疫组织化学技术和Perls铁染色技术分别观察了黑质中多巴胺能神经元的存活情况以及黑质中铁含量的变化。结果显示:(1)急性铁负载模型组:黑质中TH阳性细胞数明显减少,而铁染色阳性细胞数明显增多,与正常对照组相比差异有高度显著性(P<0.05);(2)慢性铁负载模型组:黑质中TH阳性细胞数明显减少,铁染色阳性细胞数则明显增多,与正常对照组相比差异有高度显著性(P<0.05);(3)慢性组与急性组相比,黑质内TH阳性细胞数的减少和铁染色阳性细胞数的增多更为明显,差异有高度显著性(P<0.05)。上述结果提示,葡聚糖铁铁负载模型可引起黑质内铁增多,过量铁可导致黑质内多巴胺能神经元变性死亡,慢性铁负载对多巴胺能神经元的损伤作用大于急性铁负载损伤。     

Peritoneal effects of intravenous iron sucrose administration in rats

Intravenous iron supplementation is commonly used in uremic patients treated with peritoneal dialysis. Infusion of iron compounds results in various systemic noxious effects, mainly because of its prooxidant and proinflammatory actions. The authors studied how the intravenous infusion of iron sucrose (IS) affects intraperitoneal homeostasis in rats undergoing acute peritoneal dialysis. Experiments were performed on Wistar rats, which were infused intravenously with IS in a dose 10 mg/kg body weight or with normal saline in the controls. Simultaneously, 4-hour acute peritoneal dialysis was started. At the end of the dialysis, systemic and peritoneal inflammatory reaction and peritoneal permeability were evaluated. Compared with controls, rats exposed to IS showed increased dialysate iron concentration by +70%, P<0.001, and in the differential cell count, more eosinophils (+113%, P<0.05) and fewer macrophages (-16%, P<0.05) existed. In in vitro conditions, macrophages obtained from IS-treated rats released more tumor necrosis factor-alpha (TNF-alpha; +173%, P<0.05) upon stimulation with endotoxin. Additionally increased (+73%, P<0.01) dialysate elastase activity was found in IS-treated animals. Rats infused with IS demonstrated increased peritoneal permeability to total protein (+60%, P<0.001) as compared with control animals. When rats with simultaneous peritonitis received intravenous IS, ex vivo isolated peritoneal leukocytes generated more free radicals (+73%, P<0.05) than did cells harvested from control animals. It has been concluded that intravenous infusion of IS affects the intraperitoneal homeostasis in rats, moving it toward the inflammatory state. These changes may contribute to peritoneal damage.     

虫草素联合谷氨酰胺对LPS诱导的脓毒症大鼠炎症失衡及肝肺病理变化的影响

目的　研究虫草素（cordycepin,Cop）联合谷氨酰胺（glutamine,Gln）对脂多糖（lipopolysaccharides,LPS）诱导的脓毒症大鼠炎症失衡和肝肺病理变化的影响及其可能机制。 方法　将大鼠按体重随机分为5组：对照组、模型组（LPS组）、LPS+Cop组、LPS+Gln组和LPS+Cop+Gln组,腹腔注射LPS（5 mg/kg）诱导建立脓毒症大鼠模型。ELISA检测外周血中炎症因子IL-6、TNF-α、IL-1β和IL-10的含量;HE染色观察肝肺组织的病理损伤情况;TUNEL染色观察肝肺组织的细胞凋亡情况;Western blot检测肝肺组织中Caspase-3表达水平及NF-κB p65的磷酸化情况 。 结果　LPS+Cop组、LPS+Gln组和LPS+Cop+Gln组均能逆转LPS诱导的促炎因子（IL-6、TNF-α、IL-1β）的高表达和抗炎因子（IL-10）的低表达（P<0.05）,减轻病理损伤,抑制细胞凋亡（P<0.05）,降低凋亡蛋白Caspase-3高表达（P<0.05）,下调NF-κB p65的磷酸化水平（P<0.05）。 结论　在LPS诱导的脓毒症大鼠模型中,虫草素联合谷氨酰胺能有效改善其炎症失衡和肝肺病理变化。     

虫草素联合谷氨酰胺对LPS诱导的脓毒症大鼠炎症失衡及肝肺病理变化的影响

目的　研究虫草素（cordycepin,Cop）联合谷氨酰胺（glutamine,Gln）对脂多糖（lipopolysaccharides,LPS）诱导的脓毒症大鼠炎症失衡和肝肺病理变化的影响及其可能机制。 方法　将大鼠按体重随机分为5组：对照组、模型组（LPS组）、LPS+Cop组、LPS+Gln组和LPS+Cop+Gln组,腹腔注射LPS（5 mg/kg）诱导建立脓毒症大鼠模型。ELISA检测外周血中炎症因子IL-6、TNF-α、IL-1β和IL-10的含量;HE染色观察肝肺组织的病理损伤情况;TUNEL染色观察肝肺组织的细胞凋亡情况;Western blot检测肝肺组织中Caspase-3表达水平及NF-κB p65的磷酸化情况 。 结果　LPS+Cop组、LPS+Gln组和LPS+Cop+Gln组均能逆转LPS诱导的促炎因子（IL-6、TNF-α、IL-1β）的高表达和抗炎因子（IL-10）的低表达（P<0.05）,减轻病理损伤,抑制细胞凋亡（P<0.05）,降低凋亡蛋白Caspase-3高表达（P<0.05）,下调NF-κB p65的磷酸化水平（P<0.05）。 结论　在LPS诱导的脓毒症大鼠模型中,虫草素联合谷氨酰胺能有效改善其炎症失衡和肝肺病理变化。     

苦参碱对oxLDL 诱导的血管平滑肌细胞炎症反应及增殖凋亡的影响及分子机制研究

目的:探讨苦参碱对氧化型低密度脂蛋白(oxLDL)诱导的血管平滑肌细胞炎症反应及增殖凋亡的影响及分子机制。方法:oxLDL 处理人主动脉血管平滑肌细胞建立动脉粥样硬化模型。CCK-8 实验分析细胞活力和增殖。实时定量PCR(qRT-PCR)检测炎症因子白细胞介素1β(IL-1β)、肿瘤坏死因子α(TNF-α)、IL-10 和IL-13 的mRNA 水平。流式细胞术分析细胞凋亡。蛋白印迹检测增殖标记蛋白细胞增殖核抗原-67(Ki-67)和增殖细胞核抗原(PCNA),细胞凋亡标记蛋白B 细胞淋巴瘤-2(Bcl-2) 和Bcl-2 相关蛋白X(Bax),信号转导及转录激活子3(STAT3)和信号转导及转录激活子5(STAT5)的表达。结果:与对照组相比,造模组促炎因子IL-1β和TNF-α的mRNA 水平大大提高,抗炎因子IL-10 和IL-13 mRNA 水平则显著降低(P<0.01)。与造模组相比,模型加药组促炎因子IL-1β和TNF-α的mRNA 水平显著降低,抗炎因子IL-10 和IL-13 的mRNA 水平明显升高(P<0.05)。造模组细胞增殖倍数和细胞凋亡率明显高于对照组,模型加药组细胞增殖倍数和细胞凋亡率明显低于造模组(P<0.05)。与对照组相比,造模组Ki-67、PCNA 和Bax 的表达显著升高,Bcl-2 显著降低(P<0.01)。与造模组相比,模型加药组Ki-67、PCNA 和Bax 的表达明显减少,Bcl-2 表达明显增多(P<0.05)。造模组p-STAT3 和p-STAT5 相对蛋白表达量显著高于对照组(P<0.01)。模型加药组p-STAT3 和p-STAT5 相对蛋白表达量明显低于造模组(P<0.05)。与造模组相比,模型加药组和模型+Ruxolitinib 组Ki-67、PCNA 和Bax 的表达明显减少,Bcl-2 表达明显增多(P<0.05);模型加药+Ruxolitinib 组Ki-67、PCNA 和Bax 的表达显著减少,Bcl-2 表达显著增多(P <0.01)。与造模组相比,模型加药组和模型+Ruxolitinib 组及模型加药+Ruxolitinib 组IL-1β和TNF-α的mRNA 水平都明显降低,IL-10 和IL-13 的mRNA 水平都明显升高(P<0.05)。结论:苦参碱可通过抑制JAK/ STAT3 通路的活化起到抗炎和抑制血管平滑肌细胞增殖和凋亡的作用。     

糖尿病大鼠心肌DNA损伤及DNA修复酶表达的变化

目的探讨大鼠糖尿病心肌病变的心肌细胞DNA损伤及DNA修复酶OGG1和APE1表达的变化。方法提取糖尿病大鼠心肌组织中DNA、RNA及总蛋白。用Q-PCR检测心肌DNA损伤;用RT-q PCR和Western blot检测DNA修复酶OGG1和APE1表达的变化。用ELISA检测DNA内8羟基脱氧鸟苷(8-OHd G)的含量变化。结果糖尿病大鼠心肌mt DNA出现明显损伤(P0.05),n DNA无明显损伤,DNA内8-OHd G的含量增加(P0.05),OGG1和APE1的表达增加(P0.01)。结论糖尿病大鼠心肌组织内出现mt DNA损伤,虽然OGG1和APE1的表达是增加的,但可能并不足以修复mt DNA的损伤,导致mt DNA的损伤累积,引起心脏功能的损伤。     

Chronic iron overload in rats induces oval cells in the liver.

Liver damage induced by a variety of agents including hepatocarcinogens, alcohol, and virus induces proliferation of oval cells. In this study, iron overloading of the liver is used as a means of inducing liver damage over an extended period to ascertain whether it promotes the appearance of oval cells. Rats were fed a 2% carbonyl-iron-supplemented diet for 3 or 6 months. Extensive iron deposits appeared periportally in hepatocytes and some Kupffer cells. Iron deposition was less pronounced pericentrally. Small oval-like cells, morphologically and immunocytochemically similar to CDE-derived oval cells, were identified and quantified. They first emerged periportally and subsequently in small tracts or foci nearer central regions and stained positively for alpha-fetoprotein, pi-class glutathione S-transferase, and the embryonic form of pyruvate kinase. They contained very few iron deposits and were classified as iron free. The major difference between CDE- and iron-overload-derived oval cells was that the latter were negative for transferrin. This study shows that cellular changes occurring in iron-overloaded rat liver are similar to those observed in rats placed on a hepatocarcinogenic diet and in rats chronically exposed to alcohol.     

自制移植肝低温保存液对氧自由基的影响

背景：在肝脏移植过程中,低温保存和缺血可导致肝脏产生氧自由基而损伤肝组织。 目的：研究自制器官保存液对低温保存大鼠肝脏氧自由基的影响,并与器官保存液的“金标准”UW液进行对比。 方法：16只9周龄SD大鼠随机分为实验组和对照组,每组8只。建立SD大鼠肝脏灌注模型,分别用自制器官保存液组和UW液组灌洗肝脏,取出肝脏置于4 ℃保存液中,于保存24,48,72 h后分别检测肝脏超氧化物歧化酶、一氧化氮合酶、总抗氧化能力和活性丙二醛水平。 结果与结论：自制器官保存液对大鼠肝脏低温保存各时点超氧化物歧化酶、一氧化氮合酶、总抗氧化能力活性及丙二醛含量与UW液组比较差异均无显著性意义(P > 0.05),表明自制器官保存液能够减轻缺血再灌注后氧自由基对大鼠肝脏的损伤。自制器官保存液对低温保存大鼠肝脏在减轻氧自由基损伤方面有较好的效果,与UW液相当。     

Cellular mechanisms of toxicity and tolerance in the copper-loaded rat. II. Pathogenesis of copper toxicity in the liver

The distribution of copper has been studied in the liver of the copper-loaded rat at the ultrastructural level by X-ray electron probe microanalysis in order to clarify the pathogenesis of copper-induced damage. Male rats fed a high copper diet (1500 ppm) for 16 weeks were killed at intervals; their livers were removed and fixed in 4% paraformaldehyde and 2% glutaraldehyde for electron microscopy and were analyzed for copper by AA spectrophotometry. Three different forms of lysosomes were identified with respect to their morphology and X-ray emission profiles: Type I lysosomes appeared early and contained iron and zinc in addition to markedly elevated copper peaks, whereas later appearing Type II lysosomes included sulfur and phosphorus in addition to copper. Type III lysosomes were associated with the recovery period and contained much reduced elemental residue. Degenerative changes were not observed in any of the three types of lysosomes. Copper and other elemental residues, including sulfur, were also identified within the hepatic parenchymal cell nuclei and by contrast were associated with irreversible nuclear damage. Nuclear copper is directly injurious to this organelle and responsible for the subsequent cell death whereas copper contained within lysosomes is apparently innocuous.     

Storage of lipid droplets in and production of extracellular matrix by hepatic stellate cells (vitamin A‐storing cells) in Long‐Evans cinnamon‐like colored (LEC) rats

LEC rats spontaneously develop hepatocellular carcinoma with cholangiofibrosis after chronic hepatitis, but the mechanism of development of the hepatic injury is not clear. To investigate the role of hepatic stellate cells in induction or suppression of hepatic fibrosis, we morphologically examined the liver of LEC rats. Accumulation of copper was analyzed by the Danscher‐Timm's sulfide‐silver method. Histopathological changes were evaluated by hematoxylin and eosin staining, and by Masson's trichrome method. Activated stellate cells were identified by immunostaining method for α‐smooth muscle actin. Cytological alterations of the stellate cells were investigated by transmission electron microscopy. To evaluate the lipid content in the stellate cells, we analyzed the area of lipid droplets of the cells by morphometric analysis. Also for evaluation of the changes in the number of stellate cells, the numbers of nucleated stellate cells and parenchymal cells were counted and statistically analyzed. Hepatic parenchymal cells showed excessive accumulation of copper at 5 weeks of age. Submassive necrosis was observed at 19 weeks of age. The liver of LEC rats 1.5 years of age showed cholangiofibrosis and subcellular injury of hepatic parenchymal cells. However, no diffuse hepatic fibrosis was observed in the liver, and hepatic stellate cells around the regions of cholangiofibrosis were negative for α‐smooth muscle actin. The area of lipid droplets of a stellate cell in the liver of LEC rats was 1.6 to 1.8 times as large as that of normal Wistar rats. The hepatic stellate cells did not participate in the accumulation of collagen fibers around themselves when the cells contained a large amount of vitamin A‐lipid droplets, even though the development of hepatic lesions was in progress. Our present data are consistent with our previous hypothesis that there is an antagonistic relationship between the storage of vitamin A and the production of collagen in stellate cells. Anat Rec 258:338–348, 2000. © 2000 Wiley‐Liss, Inc.