胶原多肽铬对四氧嘧啶致小鼠肝脏损伤的保护作用

目的:研究胶原蛋白多肽铬螯合物对小鼠四氧嘧啶致肝损伤在形态结构方面的保护作用.方法:30只昆明小鼠随机分为正常对照组、四氧嘧啶模型组及胶原蛋白多肽铬螯合物(CPCC)组.胶铬组灌胃(Cr3 40μg/kg BW)28d,正常组和模型组给予等体积蒸馏水.腹腔注射四氧嘧啶造模,3d后观察肝脏形态学变化、测定肝指数并分析肝脏可溶性蛋白的变化.结果:CPCC处理使四氧嘧啶处理后小鼠肝脏肿大、肝小叶粘连现象明显改善;肝指数降低;减轻肝细胞变形、肝窦淤血、炎症细胞浸润及肝细胞空泡样变、血管内皮细胞损伤,核变性程度.同时CPCC能有效防止四氧嘧啶所致小鼠肝脏可溶性蛋白的变化.结论:CPCC对四氧嘧啶致小鼠肝脏损伤具有明显的保护作用.     

成体大凉疣螈肝脏的组织形态学观察

本文采用HE染色和Masson染色方法,研究了成体大凉疣螈肝脏的基本组织形态和胶原纤维分布情况。解剖观察见成体大凉疣螈的肝脏发达,体积较大,分两叶,外观呈虎斑状;组织形态学观察显示其肝内结缔组织少,肝小叶分界不清晰;肝索排列呈放射状,肝细胞体积较大,胞浆丰富,细胞核位于中央或被胞质内丰富的糖原和脂滴挤到一侧,表明肝脏是其重要的贮能器官。肝实质内大量的黑色素颗粒聚缩形成黑色素团,分析认为这与已报道的蝾螈科种类相似,是低氧环境下保护性适应的结果。染色结果表明,成体大凉疣螈肝脏表面覆盖有浆膜,肝小叶内分布有较为丰富的胶原纤维。     

梭鱼消化系统的组织学研究

采用石蜡切片等组织学研究手段,以生活于海水和咸淡水中的梭鱼Liza haematocheila作为实验材料,对其消化系统的组织学结构进行了观察.比较了消化道各部分粘膜褶皱的高低、多少、疏密程度,粘膜上皮细胞的类型,杯状细胞在数量上的变化以及消化道肌层的肌肉组织类型和肌细胞的排列方式.结果显示:咸淡水梭鱼的肠道中杯状细胞的数量多于海水梭鱼,食道是横纹肌,但其它消化道均为平滑肌.肝脏中肝小叶不明显,肝细胞索明显.胰腺呈弥散状分布,其中有胰岛存在.     

葛根素对大鼠肝脏缺血再灌注损伤的保护作用

目的:观察葛根素预处理时大鼠肝脏缺血再灌注损伤的保护作用.方法:雄性SD大鼠,建立肝脏缺血再灌注模型(HIR).随机分为假手术组、HIR组和HIR-葛根素预处理组.分析各组动物血清中谷草转氨酶(AST)、谷丙转氨酶(ALT)及乳酸脱氢酶(LDH)含量的变化,观察肝组织病理学的改变.结果:肝脏缺血再灌注损伤后,与假手术组比较,血清中AST、ALT、LDH含量均显著增加,同时肝脏门静脉周围瘀血明显,可见少量散在的肝细胞片状坏死灶,有少量炎性细胞和单核细胞浸润,肝细胞肿胀、脂肪空泡变性、核浓缩;经40mg/kg剂量的葛根素预处理7天后,与模型组相比,血清中AST、ALT、LDH均显著降低,肝脏的瘀血明显较模型组轻,肝小叶结构基本正常,微血管未见明显损伤,窦间隙稍宽,细胞变性坏死不明显,偶见少量肝细胞坏死.结论:葛根素预处理对大鼠缺血再灌注肝脏损伤有一定的保护作用.     

中国大鲵肝脏的超微结构

应用透射电镜对中国大鲵的肝脏进行了超微结构研究.观察表明,大鲵肝不具肝小叶,与其他脊椎动物有所不同.肝细胞含有单个卵圆形的核;细胞质内含有粗面内质网、高尔基囊泡、线粒体、糖原颗粒和脂滴等细胞器和内含物.胆小管由两个相邻肝细胞质膜凹陷围成,而肝血窦则由内皮细胞的胞质构成.胆小管腔和窦周隙内浸润许多由肝细胞发出的微绒毛结构.还发现了枯否氏细胞和贮脂细胞.还讨论了中国大鲵肝脏的一般形态结构特点.     

猞猁肝脏的组织结构观察及EGF在肝脏中的表达

利用切片方法观察了猞猁Felislynx肝脏的组织结构,应用免疫组织化学方法检测了表皮生长因子(EGF)在肝脏中的表达。结果显示,肝脏外被覆一层结缔组织薄膜,肝小叶不规则且分界不清,肝板、肝血窦及狄氏间隙围绕中央静脉呈放射状排列,肝板由一排肝细胞构成。肝细胞呈圆形或多边形,多为单核,少数具双核,肝细胞间比较松散。肝血窦发达,内可见血细胞。EGF阳性反应主要定位于肝细胞质中,表明EGF可能参与细胞新陈代谢过程的调控。     

安南龟肝脏和肾脏的组织学观察

采用常规石蜡切片对安南龟的肝脏和肾脏进行了组织学观察。研究结果发现,肝脏分为3叶,肝实质内结缔组织少。肝脏由无数肝小叶构成,肝小叶分界不清。肝细胞为多角形的腺上皮细胞,细胞核圆球形,位于中央。胆小管沿着肝细胞索向肝小叶四周放射并连成细长的微细管道。肾脏由肾小体、颈段、近曲小管、中间段、远曲小管和收集管6部分构成,肾小体由肾小球和肾小囊组成,在肾小体附近可见致密斑样结构,未见髓袢结构。肾小球由盘曲的毛细血管构成。肾小囊是肾小管的起始端,由内、外两层壁层构成,内层与肾小球的毛细血管紧贴,外层为单层扁平上皮细胞。     

凹耳臭蛙消化系统解剖学及组织学观察

对凹耳臭蛙Odorrana tormota消化系统进行了解剖学及组织学观察。消化道可以分为口腔、咽、食道、胃、十二指肠、回肠和直肠,末端开口于泄殖腔。肝脏和胰腺为消化腺。消化道管壁的组织结构均为4层结构,由管腔向外依次为黏膜层、黏膜下层、肌层和浆膜。胃黏膜层中含有许多胃腺,可明显分为腺颈部和腺体部。小肠含有十二指肠腺,直肠含有直肠腺。肝脏发达,分为左、中、右3叶,肝小叶界限不明显。胰腺中的腺泡由腺细胞围成。凹耳臭蛙肠全长与头体长之比为0.44～0.91,是迄今为止报道的无尾两栖类中最小的。     

东方蝾螈肝脏形态学与组织学观察

对东方蝾螈Synops orientalis的肝脏进行了组织学观察.结果 如下:东方蝾螈肝脏分为5叶,每叶由许多肝小叶组成.中央静脉位于小叶中央,肝细胞排列成肝细胞索(肝板),以中央静脉为中心向周围呈放射状排列.肝细胞索或肝细胞团之间的间隙为形状不规则、大小不等的肝血窦,窦壁由一层内皮细胞构成,间有枯否氏细胞,其核为细长状,有数目不等突起.肝细胞间有狄氏间隙,肝细胞呈多边形,胞核为圆形或卵圆形.肝实质内有大量色素沉着.并将东方蝾螈肝脏和其他动物肝脏进行了比较.     

食蚊鱼消化系统的组织学观察

食蚊鱼的消化道由口咽腔、食道、肠和肛门组成。口咽腔内有味蕾分布。食道粘膜为复层扁平上皮,粘膜内有粘液细胞。肠可分为前后两段,皱襞高度、肌层厚度有差异。消化腺包括肝脏和胰腺。肝小叶不明显,雌雄肝脏的显微结构不同。胰腺呈弥散型,一部分分布在肝脏内,另一部分和消化道伴生。讨论了食蚊鱼消化系统的特点与食性的关系。     

商城肥鲵肝及胰的解剖学与组织学观察

利用常规H.E和改良甲苯胺蓝染色方法(modified toluidine staining,MTB),对商城肥鲵(Pachyhynobius shangchengensis)肝、胆囊和胰的解剖学、组织学以及上述器官的肥大细胞进行了观察。结果表明,商城肥鲵的肝小叶不明显,肝索互相连接成网状,肝细胞核大,单核,少数2～3核,肝侧缘细胞胞体大,有的达70μm,但核质比小。肝中存在大量的色素细胞。胆囊黏膜上皮为单层扁平或立方上皮,未见形成皱襞。胰中结缔组织不发达,细胞界限不清,胞核大。除肝的门管区、肝门静脉区和胰的胰管周围分布有较多的肥大细胞外,肝和胰中其他区域分布很少,胆囊壁内有较多的肥大细胞。     

Induction and origin of hepatocytes in rat pancreas

2-[4(2,2- Dichlorocyclopropyl )phenoxy]2-methyl propionic acid (ciprofibrate), a peroxisome proliferator , induced hepatocytes in the pancreas of adult male F-344 rats when added to their diet at a dosage of 10 mg/kg body weight for 60-72 wk. These cells are morphologically indistinguishable from hepatic hepatocytes and were usually localized adjacent to islets of Langerhans with extensions into surrounding acinar tissue. A significant increase in the volume density of peroxisomes, together with immunochemically detectable amounts of two peroxisome-associated enzymes, was observed in pancreas with hepatocytes of rats maintained on ciprofibrate. Uricase-containing crystalloid nucleoids, specific for rat hepatocyte peroxisomes, were present in pancreatic hepatocytes. These structures facilitated the identification of cells with hybrid cytoplasmic features characteristic of pancreatic acinar and endocrine cells and hepatocytes. Such cells are presumed to represent a transitional state in which pancreas specific genes are being repressed while liver specific ones are simultaneously expressed. The presence of exocrine and/or endocrine secretory granules in transitional cells indicates that acinar/intermediate cells represent the precursor cell from which pancreatic hepatocytes are derived.     

Transgenic mice expressing osteopontin in hepatocytes as a model of autoimmune hepatitis

Osteopontin, a crucial factor for Th1 immune response, is expressed in stellate cells and macrophages activated in injured liver. To clarify the role of osteopontin in inflammatory changes in the liver, we attempted to establish transgenic mice expressing osteopontin in hepatocytes. Mouse osteopontin cDNA, cloned from concanavalin-A-stimulated spleen cells in C57BL/6 mice, was constructed into the vector containing serum amyloid-P component promoter. This construction was microinjected into fertilized eggs of C57BL/6 mice, and 4 lines of the transgenic mice were obtained. Western blotting and immunohistochemistry revealed that osteopontin was expressed in hepatocytes, but not in non-parenchymal cells, in the transgenic mice. The mean osteopontin concentrations in the liver and plasma in the mice were 13 and 2.6 times higher than those in negative littermates. Antinuclear antibody was positive in the plasma in 50% of the transgenic mice. In the transgenic mice later than 12 weeks of age, mononuclear cell infiltration in the liver developed, and these cells were positive for CD8 and HLA-DR. Plasma ALT activity was increased with focal necrosis in hepatic lobules in the transgenic mice later than 24 weeks of age. The transgenic mice expressing osteopontin in hepatocytes may be useful as a model of autoimmune hepatitis.     

Distribution of taurine-like immunoreactivity in the mouse liver during ontogeny and after carbon tetrachloride or phenobarbital intoxication

Summary The ontogenic pattern of development of taurine-like immunoreactivity (TLI) was studied in the mouse liver. The effect on adult mice of carbon tetrachloride or phenobarbital treatment was also examined. Light-microscopically, granules of TLI were first found in the liver from 17-day-old embryos, diffusely distributed throughout the lobules. These positive granules increased with age, were most numerous in the two-week-old mouse, and were notably decreased in the central region of some lobules in the three-week-old mouse. In mature mice, hepatocytes containing TLI-positive granules were distributed unevenly in each liver lobule, and were located predominantly in the peripheral region. Electron-microscopically, TLI was observed in small vesicles in the cytoplasm of hepatocytes and was found mainly in the cisternal lumen of smooth-surfaced endoplasmic reticulum. Some taurine-positive vesicles surrounding the reticulum seemed to associate with the protoplasm. Similar positive vesicles were often located near the bile canaliculi. In carbon tetrachloride-intoxicated mature mice, TLI was no longer limited to the peripheral region of lobules; hepatocytes situated in the central region of lobules also contained intense TLI. In mice injected with a small and repeated dose of phenobarbital, the distribution pattern of TLI was similar to that in the untreated group. However, in mice injected with a large dose of phenobarbital, TLI was markedly increased, especially in the central region of lobules. The results demonstrate that the distribution pattern of TLI in mouse liver changes during development, and that the pattern in mature mice is affected by intoxication with carbon tetrachloride or a toxic dose of phenobarbital.     

Human liver model systems in a dish

The human adult liver has a multi‐cellular structure consisting of large lobes subdivided into lobules containing portal triads and hepatic cords lined by specialized blood vessels. Vital hepatic functions include filtering blood, metabolizing drugs, and production of bile and blood plasma proteins like albumin, among many other functions, which are generally dependent on the location or zone in which the hepatocyte resides in the liver. Due to the liver's intricate structure, there are many challenges to design differentiation protocols to generate more mature functional hepatocytes from human stem cells and maintain the long‐term viability and functionality of primary hepatocytes. To this end, recent advancements in three‐dimensional (3D) stem cell culture have accelerated the generation of a human miniature liver system, also known as liver organoids, with polarized epithelial cells, supportive cell types and extra‐cellular matrix deposition by translating knowledge gained in studies of animal organogenesis and regeneration. To facilitate the efforts to study human development and disease using in vitro hepatic models, a thorough understanding of state‐of‐art protocols and underlying rationales is essential. Here, we review rapidly evolving 3D liver models, mainly focusing on organoid models differentiated from human cells.     

The influence of hepatoprotector 2-ethylthiobenzimidazole hydrobromide (bemithyl) on the content of glycogen in cirrhotic rat liver hepatocytes located in various microenvironments

Using absorption and fluorescent cytophotometry methods, glycogen contents were studied in hepatocytes located in liver lobules and in hepatocytes, which make the general population of these cells in normal and cirrhotic rat liver. In cirrhosis, the content of glycogen in hepatocytes located in lobules obviously rises in comparison with the norm, but to a lesser degree, than in hepatocytes making the general population of these cells in cirrhotic liver. The content of glycogen in hepatocytes, located in lobules of pathologically changed liver in bemithyl treated rats, did not differ from the norm. At the same time, the glycogen content in hepatocytes, representing the general population of these cells in cirrhotically altered bemithyl injected rat liver, remained higher than in the norm. The data obtained indicate that distinctions in particular cell microinvironment, obviously present in cirrhotic liver, render essential influence on hepatocyte functional activity.     

封闭群草原兔尾鼠肝脏和胰腺的组织学观察

首次对封闭群草原兔尾鼠的肝脏、胰腺进行了组织学观察,结果表明：1．草原兔尾鼠的肝脏纤维组织极少,肝小叶间界限不明显;部分中央静脉周围可见少量毛细胆管;门管区较少,分布不均匀,其静脉形状不规则、腔大,胆管及动脉则较小。2．胰腺分叶清晰,腺泡细胞较大,胞浆多呈嗜酸染色;小叶中部腺泡着色较深,外侧腺泡着色较浅;胰岛大小不等,细胞排列呈不规则索状,光镜下未见特殊改变。