鳗鲡肝脏,脾脏显微与超微结构

经光镜和电镜观察发现：鳗鲡肝脏的肝小叶不规则。肝细胞胞质内翕含多种细胞器及包含和,胆小管由２－４个肝细胞围成,相邻肝细胞间有连接复合体封闭胆小管。血窦为有孔型,孔处无隔膜,内有巨噬细胞。窦周隙明显,未见贮脂细胞。肝猾胆小管腔与窦周隙面伸出许多指状微绒毛。脾脏内白髓中淋巴细胞聚集成群,无未见明显脾小结,淋巴鞘,红髓由脾索与脾窦组成,动脉分支末端（壁厚的毛细血管）可开放于红髓,无明显巨噬细胞中心,脾窦     

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.     

不同生殖期鳜肝脏超微结构变化的观察

应用透射电镜对生殖季节与非生殖季节鳜肝脏超微结构的变化进行了观察。鳜肝细胞含有单个卵圆形的核,核仁清楚;细胞质内含有粗面内质网、线粒体、糖原颗粒和脂滴等细胞器和内含物。胆小管由相邻的数个肝细胞质膜凹陷围成,而肝血窦则由内皮细胞的胞质构成。还发现了贮脂细胞、枯否氏细胞和成纤维细胞。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。鳜肝细胞的超微结构在产卵前后呈现明显变化：产卵前的肝细胞内富含线粒体、糖原颗粒和脂滴,粗面内质网发达;而产卵后的肝细胞内核仁发生迁移,部分细胞核囊泡化,糖原颗粒和脂滴排空,少数肝细胞具双核结构。非生殖期多数肝细胞核含有双核仁结构,胞质内溶酶体数量增多。     

赛加羚羊部分器官组织学结构观察

为了解世界濒危物种、国家Ⅰ级保护野生动物赛加羚羊（Saiga tatarica）主要器官组织的结构特征,本研究利用石蜡组织切片技术,对1只因胎衣不下死亡的雌性成年赛加羚羊心、肝、脾、肺、肾的组织结构进行了观察。赛加羚羊心肌纤维发达,呈圆柱状,有分支,其胞核位于细胞边缘,各心肌纤维分支末端相互连接构成肌纤维网,闰盘明显。肝组织致密,间质少,肝小叶分界不清,切面呈不规则的多边形,肝细胞以中央静脉为中心呈放射状排列。脾的被膜较厚,脾小梁由被膜和脾门的结缔组织伸入脾实质形成,相互连接构成脾的粗支架;实质部分可明显分为白髓和红髓,白髓主要分布在脾内小动脉周围,其内部脾小结形状为圆形或椭圆形;红髓主要分布于白髓区周围,其内充满大量的红细胞。肺实质导气部主要可见细支气管和终末细支气管,其中,细支气管的管腔面富含纵行皱襞,黏膜上皮为假复层柱状纤毛上皮;呼吸部可见大量的肺泡管、肺泡囊和肺泡,肺泡结构清晰可见。肾为平滑单乳头肾,由被膜和实质构成,实质可明显分为皮质与髓质,皮质内可见大量肾小体和少量结缔组织。总体而言,与其他同类型反刍动物相比较,赛加羚羊各主要器官的组织结构未见有明显差异。     

瓦氏黄颡鱼和岩原鲤脾脏的组织学观察

运用组织学方法对瓦氏黄颡鱼和岩原鲤脾脏的显微结构进行了研究.瓦氏黄颡鱼和岩原鲤脾脏被膜薄,仅由一层单层扁平上皮细胞和结缔组织纤维构成,脾小梁明显,红髓和白髓混合,无明显的分界,鞘毛细血管发达;瓦氏黄颡鱼脾小梁细而少,白髓中淋巴细胞密集,在靠近被膜的脾实质边缘区域密集的淋巴细胞形成外形类似淋巴小结的结构,巨噬细胞聚集形成明显的巨噬细胞中心;岩原鲤脾小梁发达,伸入脾实质将脾脏分隔成一个个的小叶,白髓中密集的淋巴细胞较少,未见类似淋巴小结的结构,巨噬细胞分散存在,无明显的巨噬细胞中心.     

汞离子及铬离子对黄鳝脾免疫细胞的影响

采用毒性实验方法,用不同浓度的汞离子(Hg2+)、铬离子(Cr6+)分别处理黄鳝(Monopterusalbus),经1、2、4、8 d后,通过光镜观察黄鳝脾组织结构及免疫细胞数量的变化。结果表明,对照组黄鳝脾被膜较薄,未见明显的小梁,实质由红髓和白髓构成。白髓中淋巴细胞聚集成群,未见明显脾小结,但可见动脉周围淋巴鞘。红髓由脾索与脾窦组成。脾中有椭圆体,其末端向脾髓开放。黑色素巨噬细胞中心形成。经两种重金属离子分别染毒后的黄鳝脾与对照组相比,组织结构表现出相似的变化,即随着重金属离子浓度的增加和染毒时间的延长,脾组织中的黑色素巨噬细胞中心逐渐增大、增多,最后减少;黑色素巨噬细胞先增加后减少。淋巴组织逐渐松散,排列稀疏混乱,淋巴细胞界限逐渐不清晰,呈退化趋势,数量先增加后减少。粒细胞数量的变化趋势与淋巴细胞一致。红血细胞大量破坏,血窦扩张。     

鲤鱼和鲫鱼脾脏显微结构和亚显微结构的研究

鲤鱼和鲫鱼的脾脏中都没有小梁,其红髓和白髓是混合的。脾脏中都有椭圆体,其末端向脾髓开放。脾髓的纤维网眼中缺乏血管壁,椭圆体毛细血管中的血液可直接流入脾髓网状结缔组织的腔隙中。腹腔注射墨汁的鲫鱼,2小时后即可在椭圆体的巨噬细胞中看到碳粒的积累,可见脾脏的过滤作用主要在椭圆体中进行。在注射墨汁的鲫鱼脾脏中,黑色素巨噬细胞中心比未经注射鱼的脾脏明显,且数量增多,它和哺乳动物淋巴结和脾脏中的生发中心结构和功能都不相同。     

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.     

天然虫草对小鼠脾脏影响的组织化学和免疫细胞化学的观察

本文用３０只成年雄性小鼠,分为实验和对照两组。实验组每日灌服虫草液一次,共７日。对照组每日灌服生理盐水一次。按时将动物处死,取其脾脏进行组织化学和免疫细胞化学染色。结果显示：（１）虫草组小鼠脾脏白髓成份增加,生发中心明显,嗜派罗宁细胞增多。显微分光光度计检测结果显示虫草组脾脏内ＤＮＡ含量高于对照组,表明虫草能促进小鼠脾脏ＲＮＡ和ＤＮＡ的合成。（２）虫草组脾内ＩｇＧ＋和ＩｇＭ＋浆细胞明显增加,边缘区变宽,可能虫草有促进抗体形成的作用。此外本实验还证明,两组小鼠脾内巨噬细胞数量无明显差别     

肝缺血再灌流损伤和复方丹参保护作用的实验研究

观察大鼠肝脏缺血后再灌流时酶组织化学及超微结构的变化,同时观察复方丹参的保护作用。结果显示：肝缺血２小时后再灌流３小时,肝ＳＤＨ、Ｍｇ２＋－ＡＴＰａｓｅ、Ｇ－６－Ｐａｓｅ的活性明显降低,ＬＤＨ、ＡＣＰ的活性明显增强。超微结构变化表现为肝细胞内线粒体肿胀、嵴断裂、空泡样变,粗面内质网颗粒明显减少,肝窦扩大、窦壁内皮细胞肿胀,胆小管扩张,微绒毛减少、断裂。复方丹参对肝细胞的缺血再灌流损伤有明显的保护作用     

Scanning electron microscopy of normal rat liver: the surface structure of its cells and tissue components.

Scanning electron microscopy (SEM) allows the surface ultrastructure of intrahepatic cells and other tissue components of liver to be delineated. Excellent depth of focus of the SEM makes it possible to visualize surfaces of intact cells in their native configurations. This report details the surface characteristics and inter-relationships of hepatocytes and hepatic plates, sinusoidal endothelial cells and sinusoids, presumed Kupffer cells, vessels, bile ducts, connective tissue, and the capsule of rat liver. Hepatocytes present three structurally distinctive faces--the intercellular face containing flat surfaces and bile canaliculus, the sinusoidal face, and the connective tissue face which abuts portal tracts and hepatic veins. Sinusoidal endothelium is penetrated by large (1 to 3 mum) and small (0.1 mum) fenestrae, the latter occurring in clusters of up to 50. The width of bile canaliculi and distribution of large fenestrae vary proximodistally along hepatic plate or sinusoid. The cells of portal bile ductules contain microvilli located in linear rows and sparse cilia. Endothelium of hepatic artery and of portal vein is sparsely fenestrated.     

Structure of rat liver sinusoids and associated tissue spaces as revealed by scanning electron microscopy

Summary The inner surface of sinusoids and adjacent hepatocytes have been examined by scanning electron microscopy. The endothelial cells lining the sinusoids show large numbers of fenestrations which vary greatly in size and arrangement. Some are very small (0.1 m) and arranged in clusters; others that are much larger (1.0 m) are subdivided by slender strands of cytoplasm. At sites where the larger fenestrae are present it is evident that the endothelial lining of the sinusoid is double. This may represent a kind of structural assurance against complete breakdown of what seems to be a very thin and fragile endothelial wall. Junctions between adjacent endothelial cells have not been found in these preparations.The open continuity of the sinusoid is occasionally interrupted by slender extensions of cells morphologically distinct from the thin fenestrated endothelial cells. These possess a characteristically textured surface and are thought to represent stellate Kupffer cells.The SEM images describe the subendothelial Spaces of Disse as being larger and as having more extensive ramifications than is generally evident from transmission micrographs. The space, limited on one side by the hepatocyte with numerous microvilli and on the other by endothelial cells, appears actually to be only part of an extensive labyrinth of intercellular channels. These connect the more discrete Spaces of Disse and extend into the narrower spaces between the hepatocytes. The total effect of this system is to expose the greater part of the liver cell surface to the blood filtrate. Microvilli populate the hepatocyte surfaces except for narrow margins which border the bile canaliculi. Whether their presence coincides with the adsorbing surfaces and their absence with secreting surfaces can be decided best by experimental studies.This work was supported in part by a contract from the Special Virus Cancer Program, National Cancer Institute. The study was made while Dr. Motta was a guest investigator and Fulbright Scholar in the Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado.     

Numerical simulation of flow characteristics in a permeable liver sinusoid with leukocytes

Double-layered channels of sinusoid lumen and Disse space separated by fenestrated liver sinusoidal endothelial cells (LSECs) endow the unique mechanical environment of the liver sinusoid network, which further guarantees its biological function. It is also known that this mechanical environment changes dramatically under liver fibrosis and cirrhosis, including the reduced plasma penetration and metabolite exchange between the two flow channels and the reduced Disse space deformability. The squeezing of leukocytes through narrow sinusoid lumen also affects the mechanical environment of liver sinusoid. To date, the detailed flow-field profile of liver sinusoid is still far from clear due to experimental limitations. It also remains elusive whether and how the varied physical properties of the pathological liver sinusoid regulate the fluid flow characteristics. Here a numerical model based on the immersed boundary method was established, and the effects of Disse space and leukocyte elasticities, endothelium permeability, and sinusoidal stenosis degree on fluid flow as well as leukocyte trafficking were specified upon a mimic liver sinusoid structure. Results showed that endothelium permeability dominantly controlled the plasma penetration velocity across the endothelium, whereas leukocyte squeezing promoted local penetration and significantly regulated wall shear stress on hepatocytes, which was strongly related to the Disse space and leukocyte deformability. Permeability and elasticity cooperatively regulated the process of leukocytes trafficking through the liver sinusoid, especially for stiffer leukocytes. This study will offer new insights into deeper understanding of the elaborate mechanical features of liver sinusoid and corresponding biological function.     

The reaggregation of adult rat liver cells maintained in vitro

The reaggregation of dissociated adult rat liver cells maintained in vitro for up to 96 h is described. Cultures were examined by dark-ground fluorescence and electron microscopy. Spaces resembling bile canaliculi were formed between reaggregated hepatocytes. Desmosomes and ‘tight’ junctions were formed between hepatocytes but ‘gap’ junctions were not detected. In older cultures structural damage was observed in many hepatocytes and some of them ingested cell debris by phagocytosis. Structures resembling bile ducts and sinusoids were also formed but complex association between all three types of cell aggregate was not observed.     

Cultivation of adult rat hepatocytes on 3T3 cells: expression of various liver differentiated functions

Adult rat hepatocytes were maintained in culture for at least 1 month without losing the expression of their differentiated functions; they were cultured on lethally treated 3T3 fibroblasts inoculated at 35,000 cells/cm2 with medium containing 10-25 micrograms/ml hydrocortisone. Hepatocytes showed their typical morphology; they formed bile canaliculi, microvilli, and intercellular junctions with desmosomes and nexus; some formed structures that may resemble the perisinusoidal space of Disse. In addition, they showed DNA synthesis and expressed some liver-specific functions. They synthesized albumin and other proteins, which were exported to the culture medium. Like parenchymal liver cells in vivo, de novo fatty acid synthesis and esterification took place, and more than 80% of the lipids synthesized by the hepatocytes were secreted into the medium as triglycerides; they also showed cytochrome-P450 activity that was inducible with phenobarbital, suggesting that the hepatocytes have the capacity to metabolize drugs. These culture conditions allow the study of various hepatocyte differentiated functions, and they may provide the means to analyze the effect on liver of hormones, viruses and hepatotoxic chemicals and drugs; they may also indicate conditions adequate for serial growth of hepatocytes.     

Fine structure of the liver in the larval lamprey, Petromyzon marinus L.; hepatocytes and sinusoids

The ultrastructure of hepatocytes, bile canaliculi, and hepatic sinusoids of the larval lamprey, Petromyzon marinus, was examined using thin-sectioned and freeze-fractured tissues. The liver is a "tubular gland" with hepatocytes arranged in a tubular fashion around large bile canaliculi. Hepatocytes are roughly conical in shape, with their tapered apices facing a bile canalicular lumen. They possess extensive rough and smooth endoplasmic reticulum, a well-developed Golgi complex, abundant mitochondria, and varying numbers of large secondary lysosomes. Both secondary lysosomes and the Golgi complex are concentrated in the apical or peribiliary cytoplasm, indicating a possible role in bile secretion. The apical surfaces of the hepatocytes bear numerous elongate microvilli and occasional cilia, which project into the bile canaliculi. The hepatocytes are joined, apically, by junctional complexes composed of zonulae occludentes and adhaerentes. In freeze-fracture, the zonulae occludentes are of variable apicobasal depth and consist of honeycomb-like meshworks of fibrils. Spaces of variable width frequently appear in the P-face grooves, indicating that the zonulae occludentes are "leaky." Numerous communicating (gap) junctions join the hepatocytes laterally. Varying numbers of lateral microvilli project into the intercellular spaces and, basally, the plasma membrane is deeply infolded, resulting in the formation of apparently interdigitating basal processes resting upon a thin basal lamina. Sinusoids are composed of both a heavily-fenestrated, continuous endothelium, and phagocytic reticulo-endothelial (Kupffer) cells. Depsite the difference in arrangement of their hepatocytes, the mammalian and lamprey livers show similar ultrastructural features.     

Structure of the spleen of the sea bass (Dicentrarchus labrax): A light and electron microscopic study

The spleen of sea bass (Dicentrarchus labrax) is composed mainly of red pulp, whereas the white pulp is poorly developed. The red pulp consists of clear reticular cells intermingled with blood cells, sinusoids, and melanomacrophage centers (MMCs). The MMCs are enclosed by an interrupted connective tissue capsule and show some areas in continuity with the adjacent pulp. The MMCs are formed by the association of free macrophages that have phagocytosed some blood cells. Sparse white pulp is diffuse, forming a cuff around the pulp arteries and MMCs, or occurring in small groups between the splenic cords. A longitudinal artery and vein, lying side by side, extend the length of the spleen. Frequently the capillaries are surrounded by a sheath of macrophages or ellipsoids. These macrophages may contain erythrocytes in varying degrees of degradation. Lymphopoiesis and plasmapoiesis occur in the sparse lymphold areas. Abundant plasma cell groups may indicate the presence of antibody production.     

Liver ultrastructure and a new cell type in the Japanese newt, Cynops pyrrhogaster.

The liver of the Japanese newt, Cynops pyrrhogaster, has been investigated using light, scanning, and transmission electron microscopy. Hepatic parenchyma was composed of clusters and cords or tubules of polyhedral cells separated by a sinusoidal net. Hepatocytes had spherical, euchromatic nuclei with one or more nucleoli and stacked mitochondria with sparse cristae and dense bodies. Rough endoplasmic reticula formed peribiliary stacks and diffusely scattered vesicles and tubules. Smooth endoplasmic reticula were more pronounced in glycogen-rich hepatocytes. Most hepatocytes contained peroxisomes, Golgi complexes and large numbers of fat droplets within the cytoplasm along with glycogen. Some cells were mainly glycogen-storing and contained few or no fat droplets. A special feature of the newt liver was biliary atresia. Bile canaliculi had short, stout microvilli which were entirely atretic in some canaliculi. Canaliculi were sealed off by junctional complexes including zonulae occludentes and maculae adherentes. The latter showed extraordinary wider desmosomal gaps in the vicinity of the atretic bile canaliculi. The sinusoid wall was non-distinctive and contained fenestrated endothelial cells connected to Kupffer cells by zonulae occludentes. A distinctive new cell type (OG cell) was observed in the newt liver. These cells were found individually or in small clusters in proximity with the sinusoidal surfaces. They had small nuclei, a paucity of cytoplasmic organelles, but numerous, unique, osmiophilic granules of two distinct types. Less numerous Type I granules contained homogeneous electron-dense material, and a predominant Type II granule contained circumferentially arranged subparticulation. Granules of both types were detected within the cytoplasm of endothelial cells and within sinusoids together with blood elements. The function of this secretory type cell remains obscure, though it may represent a stage of melanophore.     

The architecture of the spleen of the yellow-bellied toad, Bombina variegata

The spleen of the yellow-bellied toad, Bombina variegata , consists of distinct white and red pulps. The well-developed white pulp is formed by a large central lymphocytic region around the numerous blood vessels and by its smaller peripheral ramifications, both surrounded by the more or less developed connective tissue boundary layer. Large peripheral sinuses of the white pulp, filled mostly with lymphocytes, are usually present at the inner side of this boundary. At the outer side of the boundary layer, the lymphocytic marginal zone is often observed. This zone merges into the erythrocyte-rich red pulp formed by cellular cords and small venous sinusoids.
The structure of the spleen of Bombina variegata differs considerably from the spleens of other anuran species studied so far. The highly developed white pulp and its distinct separation from the red pulp may be connected with the important role of the spleen as the main secondary lymphoid organ of B. variegata. The splenic compartmentalization makes the yellow-bellied toads a useful model for experimental immunobiological studies.     

Evidence of species differences in the ultrastructure of the Hepatic sinusoid

Summary Hepatic sinusoids in the calf have been studied by light and electron microscopy. The endothelial lining is shown to be continuous and to be associated with a prominent basement membrane. The perisinusoidal space (of Disse) contains collagen fibrils and is otherwise nearly filled with hepatic cell microvilli. Perisinusoidal cells resembling fibroblasts or reticular cells in morphology and distribution are present in moderate numbers. Hepatic sinusoids in the rat were examined for purposes of comparison. In the rat the sinusoidal lining is discontinuous and there is no identifiable basement membrane. The perisinusoidal space is larger than in the calf and contains more sparsely distributed collagen fibrils. Perisinusoidal cells have not been identified. It is suggested that the difference in structure is not artifactitious but represents a species variation. This species difference seems important to record since observations on the rat and other small laboratory animals provide the basis for most of the current generalizations about the organization of the mammalian liver sinusoid. The functional significance of the two types of sinusoidal arrangement is not clear.A preliminary report of this work was presented at the VII th International Congress of Anatomists (Wood 1960).Supported in part by Grant H-2698 from the National Institutes of Health, U. S. Public Health Service.