Effect of dexamethasone on the expression of binding sites for high-density lipoproteins in cultured rat hepatocytes (Independence of the hormone effect on the intracellular cholesterol pool)

It is shown that glucocorticoids play a key regulatory role directed toward the maintenance of an optimal level of binding and internalization of HDL₃ in hepatocytes. Their stimulatory effect on the expression of HDL receptors proves to be independent of changes in the CH content in parenchymal cells. Translated fromByulleten' Eksperimentalnoi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 50–53, January, 1994     

大鼠烫伤后早期肝细胞变化的超微结构观察及形态计量分析

用超微结构形态计量方法分析了大鼠30％烫伤后早期肝细胞超微结构的变化规律。烫伤后,肝细胞内精原迅速减少,至6小时,几乎全部消失。烫伤后2小时、6小时。肝细胞内溶酶体的体积密度、数目密度和平均体积均明显增大。线粒体于烫伤后半小时出现基质密度增加、嵴扩张,烫伤后2小时、6小时,线粒体肿胀,其体积密度、平均体积增大。实验结果提示:在严重烧伤后数小时内,肝细胞的超微结构即出现明显的改变。本文对出现这些变化的机制进行了讨论。     

丙型肝炎病毒阳性血清体外感染人肝细胞的研究

目的 研究丙型肝炎病毒(HCV)抗体(Ab)阴性,HCV-RNA阳性血清建立体外感染肝细胞模型.方法 HCV Ab阴性,HCV-RNA阳性的窗口期血清与人肝细胞共同培养,用反转录-聚合酶链反应(RT-PCR)、免疫荧光染色、Western blot、共聚焦显微镜和透射电镜等方法检测细胞内HCV核酸复制、蛋白质表达及超微结构改变.结果 细胞与病毒共同培养7～45 d,细胞内和/或培养上清中可间断检出HCV正、负链RNA;细胞浆内有HCV 核心和NS3抗原的表达;细胞超微结构有改变,并于感染后第24天时观察到类似病毒样颗粒.结论 窗口期血清中的HCV能在人肝细胞7701中复制一段时间.     

肝衰竭肝细胞移植治疗时的"种子细胞"

目前,对肝衰竭治疗主要依赖于原位肝移植,但这一治疗手段因存在多方面的困难而难以广泛开展。肝细胞移植的出现以其独特的优点将成为原位肝移植的辅助治疗甚至会替代原位肝移植。但是,肝细胞移植时最佳细胞来源的选择又成为我们面临的一个紧迫的课题,现用于研究的细胞来源多为骨髓干细胞(包括间充质干细胞和造血干细胞)、脐血干细胞及胚胎干细胞等,且在实验研究方面都取得了不同程度的研究进展。通过对这几种细胞分化为肝细胞的实验研究进展作综述,为肝细胞移植时“种子细胞”的选择打下理论基础。     

大鼠肝细胞线粒体周围内质网的三维重建

目的：研究肝细胞线粒体与内质网的空间结构关系。 方法：通过连续超薄切片重建线粒体与其周围内质网的三维模型,结果：连续超薄切片和三维模型显示：除极少量的线粒体与脂滴直接接触外,几乎每个线粒体都被内质网所包裹,大多数线粒体周围既有RER又有小囊泡状SER,少数线粒体则仅有小的SER。这些内质网与线粒体紧贴如同线粒体外壳,二者的间隙小于30nm,其间无任何其它细胞器。结论：肝细胞线粒体通常在内质网包绕下执行生理功能,二者形成的结构和功能紧系的整体。     

人肝癌细胞系HCC-9724的建立及其生物学特性

目的 建立一株肝癌细胞系ＨＣＣ－９７２４,为肝癌研究提供实验模型。方法 无菌切除肝癌手术标本,６只裸鼠右后肢皮下包埋,体内连续传３代后,取移植瘤体外培养,绘制细胞生长曲线,光镜、电镜观察细胞形态,并进行细胞周期和染铎体核形分析,用免疫荧光法测定荷瘤鼠中ＡＦＰ的表达,结果 移植模型原代获得率为３３．３％,潜伏期为５２ｄ,自第３代后肿瘤获得率为１００．０％,潜伏期为１６ｄ,该模型移植瘤具有生长,稳定,     

HDV/HBV体外感染原代培养人胎肝细胞的实验研究

目的：建立ＨＤＶ／ＨＢＶ感染人胎肝细胞体外培养系统。方法：利用ＨＤＶ／ＨＢＶ阳性血清同时感染体外２的人胎肝细胞;应用ＥＬＩＳＡ、免疫组化法、原位杂交法和斑点法检测上清液和细胞中ＨＢｓＡｇ、ＨＤＡｇ、ＨＢＶＤＮＡ和ＨＤＶｃＤＮＡ。结果：上清液和细胞中ＨＢｓＡｇ、ＨＤＡｇ、ＨＢＶＤＮＡ和ＨＤＶｃＤＮＡ在感染后第２天至第１６天均可测出,其中上清液中ＨＢｓＡｇ、ＨＤＡｇ以感染后第４天至第１２天达高峰,结论     

Effects of polychlorinated biphenyls on liver ultrastructure, hepatic monooxygenases, and reproductive success in the barbel

Polychlorinated biphenyls (PCBs) are organochlorinated micropollutants ubiquitously distributed in the environment. They are known to be strong inducers of hepatic monooxygenases in fish. This can adversely affect reproduction by increasing steroid metabolism. In this work, adult barbels were contaminated with food containing Aroclor 1260, a commercial PCB mixture from Monsanto, at environmentally relevant concentrations. A significant increase in cytochrome P450 was observed, and two particularly sensitive enzymes, ethoxyresorufin o-deethylase (EROD) and ethoxycoumarin o-deethylase (ECOD), were strongly induced. Electron microscopy revealed alterations in liver ultrastructure in contaminated fish, principally an increase in the number of cisternae of the rough endoplasmic reticulum, drastic glycogen depletion, dissolution of mitochondrial contents, and appearance of myelin figures. Contamination was also studied in relation to reproductive success in a hatchery. Contaminated males displayed no alteration in milt quality, but PCBs did alter female reproductive parameters. Total mortality of eggs and larvae increased significantly with the level of PCBs in the eggs. The most highly contaminated fish did not even spawn. All the adverse effects recorded here tended to be reversible when the intoxication ended, sometimes after only a 1-year detoxication period.     

胃选择性迷走神经切断对大鼠肝再生的影响——肝细胞体积、数量和DNA含量的研究

探讨胃选择性迷走神经切断对大鼠再生肝细胞体积、数量和ＤＮＡ含量的影响。分别测定大鼠胃选择性迷走神经切断加肝叶大部分切除及肝叶大部分切除术后７ ｄ 再生肝ＤＮＡ含量、肝细胞数和体积。用多功能显微图像测量仪测定切片中肝细胞和肝细胞核面积及肝细胞核直径。按体视学方法测算整个肝脏的肝细胞数。用细胞分光光度技术测定切片中单个肝细胞ＤＮＡ 含量。结果表明, 胃选择性迷走神经切断加肝叶大部分切除组大鼠肝细胞ＤＮＡ含量、数量及体积均较单纯肝叶切除组增加 （Ｐ＜ ０．０５）。提示胃选择性迷走神经切断对大鼠肝再生过程有一定的促进作用。     

Changes in liver regenerative factors in a case of living-related liver transplantation

Liver regeneration in a patient with fulminant hepatic failure (FHF) who underwent living-related partial liver transplantation (LRLT) was investigated regarding hepatic growth factors. The patient was a 16-yr-old Japanese male who developed severe subacute FHF. LRLT was performed using an extended left lobe of the ABO matched patient's mother. In the recipient, the pre-transplant levels of both plasma hepatocyte growth factor (HGF) and transforming growth factor (TGF)-beta were extremely high and rapidly decreased following the liver replacement. The liver volume evaluated using a CAT scan increased 195% after 2 wk in graft liver and 110% after 2 wk in the hepatectomized donor. The explanted liver (FHF liver), the liver from donor (normal liver), and the graft liver [the 3rd post-transplant day (POD 3)] were all investigated immunohistochemically. FHF liver: No liver regeneration was observed [proliferative cell nuclear antigen (PCNA) labeling index (L.I.): 0%]. In the liver, both HGF in the hepatocytes and c-met on the membrane of the hepatocytes were positive. TGF-beta was positive in the hepatocytes and no apoptosis was detected by the TUNEL method. Donor liver (POD 0): Few PCNA stained hepatocytes were detected. No HGF was detected but c-met was clearly detected on the cell membrane of the hepatocytes. Neither TGF-beta nor apoptosis was detected. Graft liver (POD 3): The PCNA L.I. was conspicuous at 40%. HGF was positive in non-parenchymal cells and c-met was positive in the cytoplasm of the hepatocytes. TGF-beta was negative while apoptosis was positive in the zone 3 hepatocytes. In conclusion, these findings suggested that the liver of the patient with FHF did not respond to liver regenerative stimulus, in part, through involvement of inhibitor TGF-beta. On POD 3, the transplanted graft was in a vigorous regenerative status in comparison to that in the hepatectomized donor. The HGF/c-met system is thought to be involved in the mechanism of regeneration. Intrahepatic apoptosis was detected in the graft on the 3rd post-transplant day probably due to transient ischemia in the liver, which was not related to the Fas/Fas-ligand system.