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1.
Lacrimal glands of 12 dogs free of ocular disease were examined to determine the normal structure of these glands. The glands consisted of tubuloacinar cells that ultrastructurally and histochemically were of a single type of secretory cell in the tubules and possibly 3 types of secretory cells in the acini. The tubular epithelium contained homogenous electron-dense granules that stained as neutral glycoconjugates (periodic acid-Schiff positive and Alcian blue and high iron diamine negative). The predominant acinar cells contained granules of lesser electron density than those of the tubules, and stained as sialomucin (Alcian blue [pH 2.5] and periodic acid-Schiff-positive, and high iron diamine-negative). A second type of acinar cell was in peripheral lobules that ultrastructurally and histochemically appeared like lipid granules (positive with oil red O and osmium tetroxide). Ultrastructurally, a third type of acinar granule was finely granular, electron-lucent, and frequently coalesced. It was not readily apparent whether the latter was an artifact, a stage in the maturation of the sialomucin granules, or a third type of acinar granule. Individual acinar cells usually had a predominance of 1 granule type, but greater than 1 granule type could be found in some cells. The basal surfaces of the acinar, tubular, and ductal cells were incompletely ensheathed by myoepithelial cells. Plasma cells, lymphocytes, mast cells, endothelial cells, fat cells, and Schwann cells composed the cellular elements of the interstitium. Lymphocytes, mast cells, and nerve endings also were found in the parenchyma.  相似文献   

2.
鹅胸腺APUD(样)细胞的超微结构   总被引：2，自引：0，他引：2  
应用透射电镜在鹅胸腺内发现一种ＡＰＵＤ（样）细胞。这种细胞形态不规则,有突起伸入相邻细胞之间;胞核圆形,电子密度低,核仁明显;胞质内含有粗面内质网、线粒体等丰富的细胞器。其主要特征是含有大量的多分布于胞质一侧的膜包小分泌颗粒,呈圆形或椭圆形,大小不等,直径１１０～５５０ｎｍ,有些颗粒在界膜与内含物之间可见低电子密度的晕轮。根据其超微结构特征,可将颗粒分为３型：Ⅰ型颗粒为中等电子密度;Ⅱ型颗粒为均质状高电子密度;Ⅲ型颗粒在中等电子密度中含有一高电子密度的核芯。作者认为这种细胞属于内分泌细胞,并且很可能是分泌肽类激素的ＡＰＵＤ细胞。  相似文献   

3.
Morphological studies to localize mast cells in the wall of the convoluted and straight parts of the proximal tubules of the domestic swine kidney were performed. Kidney perfusion was carried out in 8-month-old pigs and semi-thin and ultrathin sections were prepared after a routine treatment. A light microscopic study showed that mast cells were not frequently found. Most were localized in the wall of the proximal convoluted tubule, while in the proximal straight tubule wall they were fewer in number. Most of the mast cells were oval in shape, their size being typical for this species, and the granules were reddish in colour. Three types of granule containing an evenly distributed granular-fibrous substance were found by TEM examination: the first type had a single electron-optically dense belt under the membrane; the second showed optically empty spaces between the substance and the cell membrane; the granules from the third type had two parallel dense belts below the granular membrane and were the smallest in size. Some of the granules of the first type were connected with the granular endoplasmic reticulum. A very narrow intercellular area and single desmosome-like junctions were found between the mast cells and the epithelial cells. Protrusions of plasmalemma and granules outside the cells were not established. On the basis of these results and data from the scientific literature, a comparative analysis was carried out. This showed certain differences between the results obtained and previous findings on the morphology of domestic swine mast cells and granules.  相似文献   

4.
The acini of the bovine mandibular gland consist of mucous and demilunar seromucous cells. The mucous cells contain electron-lucid mucigen droplets or mucoid masses, only rarely delimited by membranes. The cisternae of the RER communicate freely. Mitochondria are scarce. The seromucous demilunar cells contain considerably more granules, and perigranular membranes are far more common. Many granules have characteristic alternating electron opaque and less electron dense areas. The prominent RER appears to be associated with a peculiar labyrinth of interconnecting tubules. Mitochondria are numerous. Numerous myoepithelial cells are observed. The cuboidal cells of the intercalated ducts lack signs of secretory activity. The columnar cells of the striated ducts have extensive infoldings of the basal plasma membrane, associated with mitochondria. The cell apex contains many granulated vesicles. Endogenous lactoperoxidase activity could be demonstrated only in the demilunar cells, within the secretory granules, the RER, including the perinuclear cisternae, as well as the labyrinth mentioned above. A positive reaction could be observed over acinar lumina and in intercellular canaliculi. The possible role of peroxidase as a component of a bactericidal system of the bovine saliva is discussed.  相似文献   

5.
恒河猴肾上腺髓质嗜铬细胞的电镜观察   总被引：2，自引：0，他引：2  
应用透射电镜观察了恒河猴肾上腺髓质含有的 3种嗜铬细胞 ,即明嗜铬细胞、暗嗜铬细胞和小颗粒嗜铬细胞的超微结构特征。明嗜铬细胞卵圆形或略微不规则形 ,电子密度较低 ,胞核圆形 ;胞质内含有大量的分泌颗粒。分泌颗粒多为圆形 ,直径 130～ 35 0 nm,根据其超微结构 ,可分为 2型 : 型颗粒 ,电子密度高 ,核芯呈均质状 ,有的核芯偏于颗粒一侧 ; 型颗粒 ,电子密度中等或较低 ,核芯为细粒状 ,不偏位。暗嗜铬细胞多边形或不规则形 ,电子密度较高 ,胞核不规则形 ;分泌颗粒与明嗜铬细胞相似。小颗粒嗜铬细胞与明嗜铬细胞相似 ,但分泌颗粒较小 ,直径 10 0～ 2 5 0 nm。  相似文献   

6.
The ultrastructural appearance at primary and metastatic sites of ten ovine small intestinal adenocarcinomas was that of scirrhous tubular adenocarcinoma. Polygonal undifferentiated tumor cells had desmosomes, folded nuclei, and moderate numbers of mitochondria but few other organelles. More differentiated cells were columnar with apical microvilli and basal nuclei. They contained granular endoplasmic reticulum, Golgi and secretory granules. Microvillus-lined intracytoplasmic lumina (5-10 micron diameter), fibrous filaments (10 nm diameter, up to 1.4 micron length) and tubular paracrystalline arrays (hexagonal symmetry, 37-nm periodicity) in lumina and secretory granules were seen in some tumor cells in all ten sheep.  相似文献   

7.
The study investigated seasonal changes in the morphology of the seminal vesicles of Eidolon helvum in a typical African tropical environment. Seminal vesicles of forty-eight bats were examined during the early rainy, late rainy and peak dry seasons, using gross anatomical, histological and ultrastructural techniques. The interlobular connective tissue septa from the external capsule demarcated the glandular parenchyma into numerous lobules of tubulo-alveolar glands. A simple cuboidal epithelium of mono- or bi-nucleated cuboidal cells lined the glandular mucosa during the rainy season. This was replaced by a bistratified cuboidal epithelium, whose upper layer of cells showed evidence of degeneration, during the dry season. The PAS-positive secretory products appeared to be numerous during the rainy season, but few and clumped together during the dry season. The mean gross weight, interlobular septal thickness, acini diameter and epithelial height of the glands varied significantly with season. Ultrastructural features of the secretory cells during the rainy season showed well-developed cytoplasmic organelles, numerous electron lucid secretory vesicles and electron-dense granules. Secretory epithelial cells of the seminal vesicles are very active during the rainy season, while regeneration of degenerated epithelium in preparation for the next reproductive cycle occurs during the dry season.  相似文献   

8.
Although many mast cells locate under the endothelial layer along the sublobular veins in canine liver, the cell function remains to be fully defined. To establish the nature of the canine mast cell, the mast cells were examined by electron microscopy. A few monocytes contacted with luminal surface of endothelial cells under which mast cells situated. To confirm the chemotaxis of monocyte by hepatic mast cells, the hepatic venous vessels were treated with a histamine releaser (compound 48/80). The monocytes invaded into the subendothelial layer and extended their pseudopodium to the degranulated mast cells. It presumes that some mediators within the mast cell granules might act as a chemotactic substance to the monocyte. On the contrary, mast cells were migrating from subendothelial layer to venous lumen under normal condition. The migrating mast cell showed strong acid phosphatase reaction in their granules. It suggests that the granules of migrating mast cell became visible to acid phosphatase activity by a physical force such as contact stimulation, and that a part of mast cells remigrate from the venous wall to other places by the blood flow. Furthermore, hepatic mast cells were revealed to contain both endothelin-1 and histamine in their granules by immunocytochemistry. As these substances have an activity of stronger venous constriction, it seems that the mast cells play an important role in the blood flow regulation of the canine liver, mast cell, monocyte.  相似文献   

9.
Ultrastructure. lysozyme and glycoconjugate activity in duodenal Paneth cells were observed concurrently in the horse. Paneth cells were seen to uniformly line the base of the equine intestinal glands. The round secretory granules have centrally located electron densities with peripherally located electron lucent halos. Histochemically, the peripheral halo layer was positively stained for carbohydrates by the periodic acid-thiocarbohydrazide-silver protein-physical development (PA-TCH-SP-PD) method and the entire granules reacted positively to the WGA. The central core area reacted with anti-lysozyme. We identified a young (Type I) and an old (Type II) cell population in the same crypt, but we suggest that the observed populations are variations of the same cell type with the varied appearance due to aging of the secretory granules.  相似文献   

10.
The morphological differences between two types of secretory cells (clear and dark) from pig carpal glands were examined. The main difference is the presence in the dark cells of secretory granules of moderate electron density, made up of acidic and neutral glycoproteins. The possible functional purposes of the carpal glands and of glycogen present in both cell types are also discussed.  相似文献   

11.
A subpopulation of purified, interepithelial lymphocytes from porcine small intestinal mucosa contained cytoplasmic granules. Toluidine blue staining revealed metachromatic granules in 13.64% (606/4,450) cells. The cells had scant organelles, a single large nucleus with obvious invagination of the nuclear membrane, and prominent chromatin. Each cell contained 1 to 10 cytoplasmic membrane-bound granules, 0.6 to 1.5 micron in diameter. These findings indicated that the granular mucosal lymphocytes are related morphologically to mucosal mast cells. The presence of serotonin in the granules, confirmed by the serotonin releasing test, provided functional evidence that granular mucosal lymphocytes are related to mucosal mast cells.  相似文献   

12.
利用超薄切片对摩杂一代水牛脑垂体前叶的腺细胞进行透射电镜观察,发现5种腺细胞各有其超微结构特征：促性腺激素细胞胞体呈圆形,直径为7.6～9.0 μm;分泌颗粒分为明显的大小2种颗粒,且电子密度高。促甲状腺激素细胞的直径为6.0～7.5 μm;分泌颗粒少而最小,且大小无显著差异,多沿质膜分布;细胞核小,多位于中央。促肾上腺皮质激素细胞多在邻近垂体神经部的腺体前叶中,细胞核不规则,常偏向一侧,分泌颗粒常于细胞周边或一端;胞体直径为7.1～8.5 μm。促生长激素细胞数量多,核大而圆,分泌颗粒多且均一,充满胞质。催乳素细胞胞体最大,直径为11.2～13.4 μm,数量多,核小,常偏于一侧;分泌颗粒多而大小不等,充满胞质。旨在为研究摩杂一代水牛生殖泌乳的内分泌调控机制提供形态学基础资料。  相似文献   

13.
The bovine pregnant corpus luteum was examined morphologically, to clarify the appearance and properties of the intramitochondrial bodies (IMB) in mitochondria of the large luteum cell (LLC). The incidence and diameter of the IMB (200–900 nm) showed a tendency to increase with the advance of pregnancy. Histochemically, the IMB reacted positively with protein, and immunohistochemically, they reacted IMB with 11 α-hydroxyprogesterone-1-11 succinyl-bovine serum albumin (P-BSA). The IMB seemed to combine with protein, and these granules did not undergo exocytosis. The cytoplasm of LLC contained another type of small electron-dense granules that were 150–200 nm in diameter, had an orifice for secretion, and reacted with relaxin. Small luteum cells (SLC) revealed crystalline-like inclusions. It is suggested that these inclusion cells participate in the synthesis of steroids.  相似文献   

14.
Follicular epithelium of the thyroid gland of the one-humped camel was examined by light and electron microscopy. It consisted of a single type of epithelial cell which varied from flattened to columnar in shape. Follicular epithelial cells were characterized by the presence of markedly dilated cisternae of rough-surfaced endoplasmic reticulum, well developed Golgi apparatus, abundant small vesicles (150 nm to 200 nm in diameter) in the apical cytoplasm, and electron-dense colloid droplets measuring from 250 nm to 1600 nm. Follicular epithelial cells frequently showed apocrine secretion into colloidal lumens. Apocrine protrusions with smooth surface were dome-like or balloon-like structures and contained a fine granular matrix. These findings indicate that the morphological features of the follicular epithelial cells of the thyroid gland of the camel are essentially similar to those of mammals except for the presence of apocrine secretion, which is unique to the camel.  相似文献   

15.
应用光镜和电镜技术,系统观察雌性中华鳖输卵管精子储存情况,显示与精子储存有关组织结构与细胞形态。结果表明,精子储存在雌性中华鳖输卵管的蛋白分泌部后部至子宫部,但各段的组织结构及精子储存量存在一定差别。蛋白分泌部后部上皮较发达,由典型的高柱状纤毛细胞和分泌细胞构成,固有膜中腺体多为泡状腺。上皮和腺体中含有大量高密度的膜性分泌颗粒,此段只有少量的精子储存。峡部较窄且固有膜内无腺体,上皮排列紧密并呈迷路样迂回分布,上皮细胞内高电子密度分泌颗粒成团集中分布在核上方。峡部管腔中分布着大量的精子,靠近管腔的精子或精子头部嵌入上皮纤毛之间或顶端凹陷的胞质中,且精子嵌入部分的细胞结构保持完整。子宫前部形成垂直于管腔的储精小管(SST),子宫上皮及此段SST上皮的分泌颗粒电子密度不均,含高密度电子致密斑,腺体中的分泌颗粒也呈现不同的内部结构。子宫部及SST的管腔中储存有大量精子。这些区段复杂的细胞结构及分泌活动,可能在精子储存中发挥重要作用。  相似文献   

16.
The present study examines the structure and ultrastructure of the bulbourethral glands in 10 sexually matured male greater cane rats raised in captivity. Following anaesthesia, the rats were perfusion‐fixed transcardially and the bulbourethral glands dissected out. Upon morphologic and morphometric analysis, the Cowper's glands were observed to have an average volume of 0.24 ± 0.08 ml, a diameter of 6.3 ± 0.6 mm and weighs 0.199 ± 0.06 g. The paired, gourd‐shaped tubuloalveolar glands were surrounded by dense connective tissues and separated into lobules by capsular septae. Each lobule consists of endpiece/secretory units and excretory ducts lined by simple glandular epithelium and pseudo‐stratified epithelium, respectively. The round end pieces consisted of 8–10 pyramidal to columnar epithelial cells with flattened, basally located nuclei and granule‐filled cytoplasm that bounded a narrow glandular lumen. The striking ultrastructural features of these secretory cells were the presence of some granules with uniform electron density and those with regions of lesser density as well as the absence of secretory vacuoles. Another unique characteristic of these secretory granules is the presence of electron dense strands radiating from their surfaces. The apical surfaces of the cells were also studded with abundant microvilli. From the findings, the structure of bulbourethral glands in the greater cane rat shows more resemblances to that of humans than to its rodent phylogeny. These findings serve as additional knowledge in the structural interpretation of the bulbourethral gland and its secretory products.  相似文献   

17.
Alkaline phosphatase (ALP) has been used in studies of neutrophil morphology and function as a marker for identifying different granule populations. In human neutrophils, ALP is found within secretory vesicles, a rapidly mobilisable vesicle population important for upregulating membrane receptors during early activation. Intra-cellular ALP activity in the heterophils of rabbits and guinea pigs, in contrast, is found only in secondary granules. The neutrophils and eosinophils of tammar wallabies (Macropus eugenii) have previously been reported to contain large amounts of ALP activity when stained using routine cytochemical techniques. To define the subcellular location of ALP in this species, cell suspensions were examined using cerium chloride cytochemistry and transmission electron microscopy (TEM). ALP was found in 2 distinct cytoplasmic compartments. One compartment displayed morphology consistent with a subpopulation of secondary granules while a second tubulo-vesicular population appeared similar to the secretory vesicles of human neutrophils. Thin tubular vesicles containing ALP were also identified within the cytoplasm of tammar wallaby eosinophils. Large numbers of ALP-containing vesicles have not been recognised previously in eosinophils and this may represent a novel cytoplasmic compartment. In both cell types, ALP-containing structures showed alteration in morphology following stimulation with N-formyl-Met-Leu-Phe (fMLP) and PMA.  相似文献   

18.
Staining and histochemical methods, immunocytochemical and electron microscopy were used to individualize the somatotropic or GH cells in the adenohypophyseal pars distalis of the kid. They are found in a sagittal section throughout the pars distalis constituting 34% of the hypophyseal cell population. They are 12.37 micron in size and have as an ultrastructural characteristic secretory spherical granules of a large size (males, 391 nm and females, 427 nm) which are very electrodense.  相似文献   

19.
The secretory units of the platypus and echidna mandibular glands consist of a single serous cell type. Secretory granules within the cells of the platypus mandibular gland stained intensely with the periodic acid-Schiff staining procedure but failed to stain with Alcian Blue, suggesting the granules contained neutral glycoproteins. Secretory granules within the mandibular glands of the echidna failed to stain with the methods used indicating little if any glycoprotein was associated with the secretory granules. Ultrastructurally, secretory granules of the platypus mandibular gland were electron dense with a central core of less electron-dense material and were membrane bound. In contrast, those of the echidna presented a lamellated appearance and also were limited by a membrane. These secretory granules appeared to form as a result of concentric layering of lamellae within cisternae of the Golgi membranes. The intralobular ductal system of the platypus was more extensively developed than that of the echidna. The striated ducts of both species were characterized by elaborate infoldings of the basolateral plasmalemma and an abundance of associated mitochondria.  相似文献   

20.
To accumulate histological information of cetaceans, the proper gastric gland of Minke whales was examined by light and electron microscopic observation. A small number of mucous neck cells and a large number of chief and parietal cells were observed in the gland. At the body to basal portions of the gland, the ratio of chief cells to other cells seemed to be large compared to the neck portion. Transmission electron microscopy revealed that the chief cell had secretory granules with middle level of electron density, and that the parietal cell contained abundant mitochondria and intracellular canaliculi. The proper gastric gland of the Minke whales may appear to secrete large amounts of digestive enzymes and have high digestive activity.  相似文献   

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