实验性肝硬变时表皮生长因子受体在肝细胞核表达的免疫组织化学研究

目的探讨表皮生长因子受体（ｅｐｉｄｅｒｍａｌｇｒｏｗｔｈｆａｃｔｏｒｒｅｃｅｐｔｏｒ，ＥＧＦＲ）在肝硬变过程中的表达和对肝再生的作用．方法采用复合因子复制肝硬变动物模型（ｎ＝３２），正常大鼠（ｎ＝８）作对照，用免疫组化研究肝硬变过程中肝细胞核ＥＧＦＲ表达的变化．结果实验组动物ＥＧＦＲ阳性肝细胞核数（／ｍｍ２）于肝硬变进程２，４，６和８ｗｋ末分别为２０８６±３９８，１６４８±３１１，１２４７±２５２，８５３±２６５．而对照组仅为０８±０４．结论大鼠实验性肝硬变模型存在着ＥＧＦＲ表达减少引起的肝再生能力下降     

表皮生长因子受体和PCNA在食管癌及癌前病变组织中的表达意义

目的探讨ＥＧＦＲ及ＰＣＮＡ的表达在食管癌发生发展过程中的临床意义．方法采用免疫组化ＳＰ法对各级食管鳞癌（Ⅰ级ｎ＝１８，Ⅱ级ｎ＝３０，Ⅲ级ｎ＝２２）、各级不典型增生（轻度ｎ＝１４，中度ｎ＝１７，重度ｎ＝１３）及正常食管粘膜（ｎ＝２０）进行ＥＧＦＲ及ＰＣＮＡ检测．结果ＥＧＦＲ及ＰＣＮＡ阳性表达在各组食管病变中呈明显递增趋势，正常组、轻度及中度不典型增生组间ＥＧＦＲ及ＰＣＮＡ表达均有显著性差异，ＥＧＦＲ阳性表达分别为：０／２０，３／１４及１０／１７；ＰＣＮＡⅠ，Ⅱ，Ⅲ，Ⅳ级表达分别为：１９／２０，１／２０，０／２０，０／２０；７／１４，６／１４，１／１４，０／１４；２／１７，７／１７，７／１７，１／１７（Ｐ＜００５）．鳞癌Ⅰ，Ⅱ级组间ＰＣＮＡ表达有显著性差异，ＰＣＮＡⅠ，Ⅱ，Ⅲ，Ⅳ级表达分别为１／１８，７／１８，８／１８，２／１８；２／３０，５／３０，８／３０，１５／３０（Ｐ＜００５）；而中、重度不典型增生与Ⅰ级鳞癌组间均无显著性差异（Ｐ＞００５）．结论食管中重度不典型增生者，其基因表达及增殖特性已具有明显的潜在恶性趋势，与食管癌的发生有直接关系，临床应对这类病例积极治疗并密切随访，以防癌变     

肝硬变门脉高压形成中血浆TNF水平的变化

目的观察ＳＤ大鼠肝硬变门脉高压形成过程中ＴＮＦ浓度与肝损伤的关系．方法采用放射免疫测定法．团体ｔ检验．结果ＴＮＦ水平（ｎｇ／Ｌ）在早（１２２±０２６）中（１２１±０２３）晚（１２３±０１７）三期肝硬变中与正常组（０９７±０２３）相比明显升高（Ｐ＜００５）；与门脉压力变化无明显相关．结论ＴＮＦ水平升高，加重了肝脏损伤和肝纤维化病变，与门脉压力变化无关．     

原发性肝癌血清性激素及组织性激素受体的研究

目的研究人体性激素水平变化与原发性肝细胞癌的关系．方法应用放免法测定肝癌组（２０例），肝硬变组（１６例）及正常对照组（２０例）血清雌二醇（Ｅ２）及睾酮（ＴＴＴ）含量，并用放免组化法（ＰＡＰ法）检测肝癌组织及肝硬变组织的雌二醇受体（ＥＲ）及睾酮受体（ＡＲ）含量．结果肝癌组血清Ｅ２含量（４４５５±９３１ｎｇ／Ｌ）明显高于正常对照组（７６６ｎｇ／Ｌ±１７０ｎｇ／Ｌ）而低于肝硬变组（６４９６ｎｇ／Ｌ±１７６ｎｇ／Ｌ）（Ｐ＜００１）；前者ＴＴＴ含量（２５３３００ｎｇ／Ｌ±５６５６０ｎｇ／Ｌ）明显低于后二者（４５８５８０ｎｇ／Ｌ±３４９６０ｎｇ／Ｌ）（Ｐ＜００１）．肝癌组织ＥＲ（８０％）较肝硬变时（４４％）明显增加（Ｐ＜００２５），且与血清Ｅ２含量有明显负相关关系（ｒ＝－０８４７３，Ｐ＜０００１）．ＡＲ阳性百分率在两者无明显差别（ｒ＝－０３１３５，Ｐ＞００５）．结论血清ＴＴＴ含量改变及肝组织ＡＲ浓度改变与肝癌无明显关系，而血清Ｅ２含量改变及肝组织ＥＲ浓度改变与肝癌的发生、发展有密切关系．提示原发性肝细胞癌是一雌激素依赖性肿瘤．     

贮脂细胞和肝细胞胶原合成能力的比较

目的为明确肝纤维化过程中细胞外基质（ｅｘｔｒａｃｅｌｕｌａｒｍａｔｒｉｘ，ＥＣＭ）的细胞来源以及贮脂细胞（ｆａｔｓｔｏｒｉｎｇｃｅｌ，ＦＳＣ）和肝细胞（ｈｅｐａｔｏｃｙｔｅ，ＨＣ）在肝纤维化胶原合成中的作用．方法用胶原酶和链霉蛋白酶Ｅ消化大鼠肝脏，结合密度梯度离心法分离培养大鼠ＨＣ和ＦＳＣ，在此基础上，用３Ｈ脯氨酸掺入结合胶原酶消化法和斑点杂交法，观察ＨＣ和ＦＳＣ胶原的合成及Ⅰ，Ⅲ，Ⅳ型前胶原基因的表达．结果发现体外培养的ＦＳＣ合成胶原的能力较ＨＣ强，约为ＨＣ的两倍（Ｐ＜００５）；ＦＳＣ胶原基因表达的水平同样较ＨＣ高（Ｐ＜００５）．结论ＦＳＣ在ＥＣＭ胶原合成中起主要作用，但ＨＣ的作用也不容忽视．     

大鼠实验性肝硬变腹水形成与TNFα的关系

目的研究大鼠实验性肝硬变晚期腹水形成与ＴＮＦα及肠源性内毒素血症的关系，探讨肝硬变腹水形成的机制．方法以大鼠为实验对象，分为正常对照组（ｎ＝８）、肝硬变对照组（ｎ＝１２）和肝硬变伴腹水组（ｎ＝１８）．实验组采用复合因子复制肝硬变动物模型．各组均测定腹主动脉血中ＴＮＦα和内毒素水平，肝硬变组还测定了腹水量．结果随着肝硬变形成，大鼠血中ＴＮＦα水平（μｇ／Ｌ）增高，各组含量分别为９０８±１０７和９５８±１２８（肝硬变组和肝硬变伴腹水组）．相关分析表明肝硬变组腹水量与血中ＴＮＦα成正相关（ｒ＝０８６，Ｐ＜００５，内毒素水平增高，并与ＴＮＦα的浓度成正相关（ｒ＝０７５，Ｐ＜００５）．结论肝硬变腹水形成与血中ＴＮＦα升高相关，而ＴＮＦα的升高则源于肠源性内毒素血症的形成．     

人类肝细胞肝癌的细胞凋亡和癌组织内血管形成的调控

目的研究肝细胞肝癌（ＨＣＣ）中细胞凋亡和血管形成的相互关系．方法采用原位末端标记技术和抗第Ⅷ因子的抗体分别检测ＨＣＣ凋亡指数和瘤内微血管的密度，同时用免疫组化法检测血管内皮细胞生长因子（ＶＥＧＦ）及其受体ｆｌｔ１和肝（癌）细胞凋亡启动基因ｆａｓ的表达．结果ＶＥＧＦ的表达主要见于微血管形成处的血管内皮细胞及其周围的瘤细胞和胆管上皮细胞，阳性率为８２７％，在ＨＣＣ组织中的表达具有普遍性．平均微血管计数为２８～４１６个／２００倍视野．在瘤组织中，微血管的密度越高的区域，ＶＥＧＦ的表达就越丰富．ＶＥＧＦ的受体ｆｌｔ１的表达见于血管内皮细胞和部分窦内皮细胞，特别是新生的微血管内皮细胞．ＶＥＧＦ阳性区域很少或不表达Ｆａｓ抗原．凋亡细胞的分布和凋亡指数与肿瘤的微血管密度呈明显的负相关（ｒ＝－０９１７，Ｐ＜００１）．结论ＨＣＣ中血管形成主要是由ＶＥＧＦ／ｆｌｔ１系统介导的．血管形成丰富的区域，细胞凋亡的敏感性和发生率降低     

慢性肝病患者血清TGF-β1与肝纤维化指标和肝组织病理的关系

目的观察慢性乙肝、肝硬变患者血清转化生长因子β１（ＴＧＦβ１）与血清肝纤维化指标和肝组织病理的关系．方法采用酶联免疫吸附试验（ＥＬＩＳＡ）测定７６例慢性乙肝、肝硬变患者（其中慢性轻度２０例、中度２０例、重度１８例、肝硬变１８例）血清ＴＧＦβ１．同时检测血清ＰＣⅢ,ＬＮ,ＨＡ．２９例作肝活检,行ＨＥ染色．结果慢性乙肝轻、中、重度及肝硬变患者血清ＴＧＦβ１水平（ｍｇ／Ｌ,１４４±５７,３５０±１０８,５０８±１３３,５７９±２２５）明显高于对照组（ｍｇ／Ｌ,９５±３４,Ｐ＜００１）,按慢乙肝轻、中、重度、肝硬变依次升高（Ｐ＜００１或Ｐ＜００５）;ＴＧＦβ１与血清ＰＣⅢ,ＬＮ,ＨＡ呈正相关（Ｐ＜００１或Ｐ＜００５）;血清ＴＧＦβ１,ＰＣⅢ,ＬＮ,ＨＡ水平随着肝组织纤维化程度的加重而增长（Ｐ＜００１或Ｐ＜００５）．结论慢性乙型病毒性肝炎、肝硬变患者血清ＴＧＦβ１与肝纤维化的血清标志以及肝组织病理改变相一致．     

胃粘膜萎缩与Hp感染淋巴组织增生的关系

目的研究幽门螺杆菌（Ｈｐ）诱生的胃粘膜相关淋巴组织（ＭＡＬＴ）增生与萎缩关系及Ｈｐ根除后淋巴滤泡（ＬＦ）消失情况．方法光镜观察２５８例Ｈｐ阳性的慢性胃炎三联（奥美拉唑、克拉霉素、痢特灵，７ｄ）药治疗前后（１ｍｏ及１ａ）及正常胃粘膜２５例的ＬＦ检出率和聚集强度．结果慢性胃炎ＬＦ总检出率为７２５％；萎缩性胃炎＞浅表性胃炎，而正常胃粘膜ＬＦ检出率为４％；慢性胃炎ＬＦ聚集强度与粘膜炎症程度呈正相关（ｒ＝０６５，Ｐ＜００１）；但与粘膜萎缩程度呈负相关（ｒ＝－０６９，Ｐ＜００１）；治疗后慢性胃炎ＬＦ检出率和聚集强度明显减低（Ｐ＜００１）；腺上皮萎缩与ＬＦ形成关系密切．结论胃ＭＡＬＴ增生及相伴的免疫反应，可能是引起Ｈｐ相关性胃炎出现胃粘膜萎缩的重要原因之一．     

肝素干预血管成形术后平滑肌细胞生长因子基因表达的研究

目的探讨肝素影响血管成形术后动脉平滑肌细胞（ＳＭＣ）增生的机理。方法建立兔动脉粥样硬化模型，行血管成形术；观察肝素对体外兔髂动脉ＳＭＣ的增生、细胞周期、转化生长因子－β１（ＴＧＦ－β１）、表皮生长因子受体（ＥＧＦＲ）、碱性成纤维细胞生长因子（ｂＦＧＦ）基因表达等的影响。结果肝素能抑制ＳＭＣ的增生，并具有浓度依赖性和时间依赖性；肝素阻止ＳＭＣ进入Ｓ期，也有浓度依赖性和时间依赖性；肝素能抑制ＴＧＦ－β１和ｂＦＧＦ信使核糖核酸（ｍＲＮＡ）的表达；在培养的兔髂动脉ＳＭＣ中ＥＧＦＲｍＲＮＡ的表达呈阴性。结论肝素抑制培养的兔髂动脉ＳＭＣ的增生与抑制ＴＧＦ－β１和ｂＦＧＦｍＲＮＡ的表达有密切关系。     

Sensitization of hepatic lipocytes by high-fat diet to stimulatory effects of Kupffer cell-derived factors: implication in alcoholic liver fibrogenesis

A high-fat diet has previously been shown to be a key factor for induction of alcoholic liver fibrosis in a rat model of intragastric ethanol infusion. To explore a possible mechanism by which the high-fat diet facilitated such an effect, the present study examined how the high-fat diet with or without ethanol affected proliferation and collagen formation of hepatic lipocytes, perisinusoidal cells that have been suggested to be involved in liver fibrogenesis. We also evaluated effects of the high-fat diet on the sensitivity of lipocytes to stimulatory effects of Kupffer cell-derived factors. Intragastric infusion of ethanol and the high-fat diet for 9 to 10 wk resulted in induction of a varying degree of perivenular fibrosis in 75% of animals. Lipocytes isolated from these animals (A) had significantly higher basal rates of proliferation (three to four times) and collagen formation (1.5 times) than those isolated from control animals, which were isocalorically infused with the high-fat diet (H) or the low-fat diet (L), or those that were fed chow ad libitum (C). Lipocytes from the H group exhibited significantly higher relative production of collagen than those from the L group, but their net collagen production was not enhanced. The dialyzed Kupffer cell-conditioned medium from the A group markedly stimulated proliferation and collagen formation of lipocytes from the groups given the high-fat diet (A and H) but had minimal effects on those from the L and C groups, establishing the order of decreasing lipocyte sensitivity from the A, H, L to C group. Similarly, lipocytes from the H and A groups exhibited a more profound responsiveness to the stimulatory effect of transforming growth factor beta 1 on collagen formation. These results demonstrate (a) that lipocytes isolated from the rats given the high-fat diet and ethanol are markedly proliferative and produce more collagen; and (b) that the Kupffer cells derived from these animals release factors that stimulate proliferation and collagen formation of lipocytes and (c) that the high-fat diet sensitizes lipocytes for stimulatory effects of the Kupffer cell-derived factors and transforming growth factor beta 1.     

Stimulation of hepatic lipocyte collagen production by Kupffer cell-derived transforming growth factor beta: implication for a pathogenetic role in alcoholic liver fibrogenesis

Transforming growth factor beta has a specific stimulatory effect on collagen formation by hepatic lipocytes, a cell type believed to be a major source of extracellular matrices in the liver. Because monocytes and macrophages are the known sources of transforming growth factor beta, Kupffer cells--resident macrophages in the liver--may also play an important role in liver fibrogenesis by releasing this cytokine and stimulating lipocyte collagen production. The present study tested this hypothesis using Kupffer cells and hepatic lipocytes isolated from a rat model of alcoholic liver fibrosis. Kupffer-cell-conditioned medium derived from the rat liver with alcoholic fibrosis, but not that from pair-fed control animals, significantly stimulated the net collagen formation of lipocytes isolated from the alcohol-fed, pair-fed control and chow-fed animals. Acidification of the Kupffer-cell-conditioned medium potentiated this effect threefold to fourfold, indicating the presence of a latent form. Fractionation of the Kupffer-cell-conditioned medium by high-performance liquid chromatography gel filtration revealed the major peak of the stimulatory activity corresponding to the molecular weight between 20 kD and 30 kD. It was completely inhibited by anti-transforming growth factor beta IgG. Furthermore, Northern blotting and hybridization of Kupffer-cell messenger RNA from alcohol-fed rats with 32P-labeled transforming growth factor beta complementary DNA demonstrated the presence of 2.5 kb messenger RNA for this cytokine. We conclude that: (a) Kupffer cells isolated from the rat liver with alcoholic fibrosis express and release transforming growth factor beta; (b) that this cytokine is largely responsible for the Kupffer-cell-conditioned medium-induced stimulation of collagen formation by hepatic lipocytes; and (c) that this may represent a possible molecular mechanism of lipocyte stimulation during alcoholic liver fibrogenesis.     

Expression of TIMP-1 and TIMP-2 in rats with hepatic fibrosis

AIM: To investigate the location and expression of TIMP-1 and TIMP-2 in the liver of normal and experimental hepatic fibrosis in rats. METHODS: The rat models of experimental immunity hepatic fibrosis (n=20) were prepared by the means of immunologic attacking with human serum albumin (HSA),and normal rats (n=10) served as control group. Both immunohistochemistry and in situ hybridization methods were respectively used to detect the TIMP-1 and TIMP-2 mRNA and related antigens in liver. The liver tissue was detected to find out the gene expression of TIMP-1 and TIMP-2 with RT-PCR. RESULTS: The TIMP-1 and TIMP-2 related antigens in livers of experimental group were expressed in myofibroblasts and fibroblasts (TIMP-1: 482±65 vs 60±20; TIMP-2:336±48 vs 50±19, P<0.001). This was the most obvious in portal area and fibrous septum. The positive signals were located in cytoplasm, not in nucleus. Such distribution and location were confirmed bysitu hybridization (TIMP-1/β-actin: 1.86±0.47 vs 0.36±0.08; TIMP-2/β-actin: 1.06±0.22 vs 0.36±0.08,P<0.001). The expression of TIMP-1 and TIMP-2 was seen in the liver of normal rats, but the expression level was very low. However, the expression of TIMP-1 and TIMP-2 in the liver of experimental group was obviously high. CONCLUSION: In the process of hepatic fibrosis, fibroblasts and myofibroblasts are the major cells that express TIMPs.The more serious the hepatic fibrosis is in the injured liver,the higher the level of TIMP-1 and TIMP-2 gene expression.     

大鼠库普弗细胞分离培养方法的改良

目的建立一种稳定、高效的大鼠库普弗细胞(KCs)分离培养方法。方法采用大鼠肝脏离体链酶蛋白酶E消化和胶原酶循环灌注消化。低速离心去除肝细胞,Histodenz不连续密度梯度离心和选择性贴壁的方法分离KCs。采用ED2 CD163、兔抗大鼠溶酶体膜相关蛋白2(LAMP2)免疫细胞化学．latex-beads吞噬实验和电镜观察来鉴定 KCs。结果KCs得率为5×107个,活率为98％,经鉴定ED2阳性细胞大于98％,LAMP2阳性细胞大于99％,吞噬试验及电镜观察证明分离所得为KCs。结论改良的分离培养方法稳定、高效,为进一步的研究打下了基础。     

枯否细胞在大鼠非酒精性脂肪性肝炎发病中的作用

目的　探讨枯否细胞在大鼠非酒精性脂肪性肝炎（non-alcoholic steatohepatitis,NASH）发病中的作用。方法　19只雄性SD大鼠随机分为模型组（10只）和正常组（9只）,分别予高脂肪饮食和标准饮食饲养12周。HE染色观察肝组织切片病理学改变,透射电镜和溶菌酶免疫组织化学染色观察枯否细胞的数量和形态。结果　模型组大鼠均出现肥胖、高脂血症伴肝细胞大泡性脂肪变、小叶内炎症细胞浸润和坏死。与正常组相比,模型组肝小叶内枯否细胞数显著增加,并呈活化状态;模型组枯否细胞变化与其肝病理学改变相一致。结论　高脂饮食大鼠肝脏枯否细胞增多,并可能与其脂肪性肝炎的发病有关。     

血管活性肠肽受体在大鼠肝脏贮脂细胞的表达及其在肝纤维化中的意义

在特异引物引导下，用反转录ＰＣＲ方法扩增出预期长度的大鼠血管活性肠肽受体（ｖａｓｏａｃｔｉｖｅｉｎｔｅｓｔｉｎａｌｐｅｐｔｉｄｅｒｅｃｅｐｔｏｒＶＩＰ－Ｒ）的ｃＤＮＡ片断（７５０ｂｐ），随后该ｃＤＮＡ片段与３２Ｐ－标记的ＶＩＰ－Ｒ探针进行Ｓｏｕｔｈｅｒｎ杂交，结果证实大鼠肝脏贮脂细胞有ＶＩＰ－Ｒ的ｍＲＮＡ表达。放射受体交联试验表明贮脂细胞上存在ＶＩＰ－Ｒ的蛋白，分子量约４０ＫＤ。不同浓度的ＶＩＰ（０．１５ｎｍ－１５０ｎｍ）作用于培养的大鼠贮脂细胞，能显著抑制细胞Ⅰ型胶原的分泌并呈量效关系（ｒ＝－０．９８９，ｎ＝６，Ｐ＜０．００１）。ＶＩＰ受体拮抗剂［Ｄ－Ｐ－ｃｌ－Ｐｈｅ６，Ｌｅｕ１７］－ＶＩＰ能减弱ＶＩＰ这一作用。这些结果表明：大鼠贮脂细胞上存在ＶＩＰ－Ｒ；ＶＩＰ通过ＶＩＰ－Ｒ影响贮脂细胞的胶原分泌并可能在肝纤维化的发病过程中起一定的调节作用。     

Isolated hepatic lipocytes and Kupffer cells from normal human liver: morphological and functional characteristics in primary culture.

The development of techniques for isolating hepatic lipocytes (Ito, stellate or fat-storing cells) from rodents has been instrumental in defining their role in hepatic vitamin A storage and fibrogenesis. In this study, we developed a method for the purification of lipocytes and Kupffer cell from wedge sections of normal human liver and examined their properties in primary culture. Sections of donor liver (400 to 600 gm) harvested but not used for transplantation were perfused in situ with University of Wisconsin solution and used for lipocyte isolation within 48 hr. Cells were isolated by catheter perfusion of the wedge through several large vessels with L-15 salts, Pronase and collagenase, followed by Larex density gradient centrifugation. Lipocytes were plated on either uncoated plastic or a basement membrane-like gel. Lipocyte and Kupffer cell yields were 2.3 +/- 0.6 x 10(5) and 8.6 +/- 1.4 x 10(5) cells, respectively, per gram of liver (n = 5). Lipocyte purity was 91% as assessed by vitamin A autofluorescence, and Kupffer cell purity was 83% as determined by uptake of fluorescinated staphylococci. Lipocytes cultured on the plastic spread within 48 to 72 hr, displaying slightly more heterogeneous retinoid droplet size than comparable rat cells; on a basement-membrane gel, the cells remained aggregated and spherical with occasional spindlelike extensions. Lipocytes on plastic expressed procollagens I and III, collagen IV and laminin by immunocytochemistry, and types I, III and IV procollagen messenger RNAs by RNAse protection. Northern blot and polymerase chain reaction, respectively. Transmission electron microscopy of lipocytes at 7 days demonstrated a prominent rough endoplasmic reticulum and contractile filaments. Scanning electron microscopy revealed a smooth cell surface with perinuclear droplets beneath the cell membrane. With continued primary culture on plastic (more than 7 days), cells appeared "activated" (i.e., increased spreading and diminished retinoid droplets) and began proliferating as assessed by nuclear autoradiography and [3H]thymidine incorporation. Kupffer cells observed by scanning electron microscopy in early primary culture displayed prominent membrane ruffling and lamellipodia. In summary, we have established a reproducible method for the isolation and primary culture of human lipocytes and Kupffer cells.     

枯否氏细胞在大鼠非酒精性脂肪性肝炎发病中的作用

目的：探讨枯否氏细胞大鼠非酒精性脂肪性肝炎（non-alcoholic steatohepatitis,NASH)发病中的作用,方法：19只雄性SD大鼠随机分为模型组（10只）和正常组（9只）,分别预高脂肪饮食和标准饮食饲养12周,HE梁色观察肝细胞切片病理学改变,透射电镜和溶菌酶免疫组织化学染色观察枯否氏细胞的数量和形态。结果：模型组大鼠均出现肥胖,高脂血症伴肝细胞大泡性脂肪变,小叶内炎症细胞浸润和坏死,与正常相比,模型组肝小叶内枯否氏细胞数显著增加,并呈活化状态,模型组枯否氏细胞变化与其肝病理学改变相一致,结论：高脂饮食大鼠肝脏枯否氏细胞增多,并可能与其脂肪性肝炎的发病有关。     

Endothelin receptors in rat liver: lipocytes as a contractile target for endothelin 1.

The endothelins (ETs) form a group of three vasoactive peptides (ET-1, ET-2, and ET-3) for which two types of cellular receptors have been identified, types A and B ET receptors (ETA and ETB receptors, respectively). To address possible targets for ETs within the liver, we isolated the four principal liver cell populations and placed them in short-term primary culture. By ligand-binding assay and mRNA levels, expression of ET receptors was greatest on hepatic lipocytes (Ito cells or fat-storing cells), which are perisinusoidal cells exhibiting features of smooth muscle cells. Moreover, lipocytes expressed both ETA and ETB receptors. The mRNA for ETB receptor, but not for ETA receptor, was detectable in sinusoidal endothelial cells and Kupffer cells; neither mRNA was detectable in hepatocytes. Both ET-1 and ET-3 elicited contraction of activated lipocytes cultured on collagen lattices; the EC50 value for ET-1 was 3 +/- 1 nM and for ET-3 was 17 +/- 12 nM. In cell isolates from injured liver (after administration of carbon tetrachloride), expression of ET receptors was unchanged. However, mRNA for ET-1 was significantly increased in activated lipocytes, suggesting an autocrine loop for the initiation of lipocyte contraction. The findings imply that ET-1 may play a role in regulating sinusoidal perfusion through its effect on lipocytes, particularly in injury states.     

IL-10对实验性肝纤维化大鼠转化生长因子β-表达的影响

目的:探讨TGFβ_1在实验性肝纤维化过程中的表达状况及IL-10对肝纤维化大鼠转化生长因子β_1(TGFβ_1)表达的影响。方法:建立大鼠肝纤维化模型并行IL-10干预实验。从正常对照组(C组)和CCl_4诱导肝纤维化模型组(M组)及IL-10干预肝纤维化组(T组)中取肝脏组织,采用S-P免疫组织化学方法检测分析不同组大鼠在肝纤维化进程的不同阶段肝组织中TGFβ_1表达的情况。结果:成功建立大鼠肝纤维化模型;随着肝纤维化程度的加重,TGFβ_1在肝组织中阳性表达明显增强;经Ridit分析,C组与M组间TGFβ_1阳性表达水平有显著性差异(P<0.01);T组TGFβ_1阳性表达较M组明显减弱,经Ridit分析,组间差异有显著性(P<0.01)。结论:TGFβ_1的阳性表达随着肝纤维化程度的进展升高,外源性IL-10对CCl_4诱导的肝纤维化中TGFβ_1的表达具有明显拮抗作用。