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1.
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   

2.
The chemical content of the secretion of the sheep lacrimal gland was analysed at the light and electron microscope levels by applying histochemical techniques and an ultrastructural histochemical method (periodic acid, thiocarbohydrazide and silver proteinate). Mucosubstance histochemistry demonstrated acidic glycoconjugates, mainly sulphated, in the mucous and seromucous glandular cells and in the apical portion of the cells lining the terminal ducts. Moreover, secretory granules, stained with PA-TCH-SP, showed a different localization of the reaction product. The presence of lysozyme was also found in the glandular serous cells. These histochemical studies demonstrate that the secretion of sheep lacrimal glands is mixed, having serous, mucous and seromucous components, and that an excellent correlation exists between the secretory granule substructure and glycoprotein localization.  相似文献   

3.
Previously, the distribution of myoepithelial cells (mecs) in the salivary glands was studied by both immunohistochemistry, and transmission electron microscopy; however, little was elucidated concerning their morphological features, especially in goats. This study was performed to investigate the correlation between the cytoarchitecture of the mecs in goat major salivary glands (parotid, mandibular, and sublingual glands) and the nature of the saliva secretion. The cytoarchitectural features of the mecs were examined by scanning and transmission electron microscopy as well as immunohistochemically. The secretory endpieces in the parotid gland are of the pure serous type, but in both the mandibular and sublingual glands they are of the mixed type. In all studied glands, the intercalated ducts were covered by mecs which, unlike the large stellate cells that surrounded the secretory endpieces, were spindle-shaped with few cytoplasmic processes. Interestingly, the mecs were found to bulge on the basal surfaces of the serous acini and intercalated ducts in all glands and to be in close contact to the seromucous tubules surface in the mandibular and sublingual glands forming a continuous network around it. In conclusion, the differences in the degree of development of the mecs as well as the number of their cytoplasmic processes may be correlated with the nature of the secretion and the number of the secretory granules. Thus these observations may have some relevance in the diagnosis of atrophy and pathogenic conditions of these glands.  相似文献   

4.
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   

5.
The prenatal development of the cat's mandibular and parotid gland was examined by means of serial section of 36 cat embryos at 14–62 days of development. Both glands were excised from the epithelium of the primitive oral cavity and branched up to day 36 of the branching phase into a specific connective tissue. This tissue contained besides fine collagenous fibres, a high amount of proteoglycans. In the subsequent separation phase, ducts and acini differentiated themselves in primitive lobules which were separated by connective tissue. In the prenatal differentiation phase, from about day 50 up to birth, intercalated ducts and striated ducts were formed. In the acini, mucous and serous cells contained different amounts of complex carbohydrates. This secretory component changed shortly before birth.  相似文献   

6.
This study aimed to investigate the major salivary glands in the southern white-breasted hedgehog (Erinaceus concolor) histologically and histochemically. Five adult males were included in this study. The results showed that anatomically the shape of the parotid, submandibular and sublingual glands of the Erinaceus concolor was respectively almost pear, elliptical to pyramidal and oval. Histologically, the parotid gland had serous acini and secretory cells showed negative reaction to alcian blue (AB) (pH = 2.5) and negative response to aldehyde fuchsin (AF), methylene blue (MB) and PAS stains. The submandibular gland was a mixed gland of mucous and serous acini. The mucous acini were strongly positive for PAS, AB, MB and AF. However, serous acini were week for PAS and negative against AB, MB and AF stains. The sublingual gland was purely composed of mucous acini. The mucous acini of the sublingual gland were strongly positives for PAS, AB and MB methods. While their reaction to the AF staining was negative. In conclusion, the histological and histochemical observations of the major salivary glands of the southern white-breasted hedgehog (E. concolor) indicated that these glands shown similarities and some special different histochemical features as compared to other mammalian species.  相似文献   

7.
The distribution of different carbohydrates in dog major and minor salivary glands was investigated using a peroxidase-labelled avidin-biotin method to demonstrate binding of six lectins (Canavalia ensiformis agglutinin [Con A], Dolichos biflorus agglutinin [DBA], Arachis hypogaea (peanut) agglutinin [PNA], Glycine max agglutinin [SBA], Tetragonolobus purpurea agglutinin [TGP] and wheat germ agglutinin [WGA]). With PNA, there was only weak staining in serous acini of parotid glands. Other lectins bound, to different degrees, to different components of the salivary glands; differences could be detected between glands and between binding of different lectins to serous and mucous acinar cells and to the epithelial cell cytoplasm, luminal surface and contents of ducts. These results provide a basis for the comparison of possible changes in carbohydrates which may occur in salivary gland diseases.  相似文献   

8.
采用免疫组织化学方法对不同日龄的长爪沙鼠颌下腺IgA的定位分布进行了研究。结果表明,长爪沙鼠的颌下腺由导管部和分泌部构成,分泌部主要由浆液腺构成,导管部包括闰管、纹管、颗粒曲管和小叶间导管等。DAB显色结果表明,IgA阳性细胞主要分布于浆液性腺泡、闰管、纹管、颗粒曲管和小叶间导管,并可分布于腺泡和腺管间结缔组织,IgA阳性产物的分布具有不均一性,无明显随年龄变化的规律性。阳性产物分布于胞质中,胞核呈阴性,对照组阴性。提示从浆细胞产生或循环而来的IgA先经结缔组织进入颌下腺组织,进而定位分布于浆液腺泡和各级导管,导管部有较多的IgA分布。  相似文献   

9.
Morphometric, histological and histochemical studies were carried out on the sublingual salivary glands of the Arabian camel (Camelus dromedarius). The glands are of the tubulo-acinar type and consist of many lobules that are composed of two types of cells, mucoserous and seromucous. The mucoserous cells form the main secretory units of the gland but seromucous cells are much more seldom and form associated acini. The former cells secrete and elaborate large quantities of neutral mucosubstances, sialomucins and little sulphomucins while only the apical portion of the latter cells shows weak to moderate activity for neutral and acid mucosubstances. The histoenzymological tests employed here detected a considerable activity of alkaline phosphatase, succinic dehydrogenase, aminopeptidase and non-specific esterases, but weak activities of cytochrome oxidase, peroxidase and no activities of triacylglycerol lipase, beta-glucoronidase and amylase. The functional significance of these findings is discussed.  相似文献   

10.
泰山螭霖鱼肠道的显微和超微结构   总被引:2,自引:0,他引:2  
采用光镜和扫描电镜技术 ,对泰山螭霖鱼 (Varicorhinusmacrolepis)的肠道进行了观察。结果表明 :泰山螭霖鱼无胃 ,食管之后是肠道 ,起始端膨大呈球状。肠道由前肠、中肠和后肠组成 ,肠管直径由前肠到后肠逐渐变小。各段肠壁均分为粘膜、肌层和浆膜 3层。粘膜上皮由柱状细胞和杯状细胞组成 ,肌层分内环行和外纵行 2层。粘膜向肠腔内突出形成许多粘膜褶 ,有的呈指状、杵状 ,有的有分支。由前肠到后肠 ,粘膜褶由高变低 ,数量逐渐减少 ;杯状细胞数目由多变少 ;肌层逐渐变薄。扫描电镜下 ,肠道的粘膜褶大体上呈纵向锯齿状 ,并且粘膜褶上还有次级皱褶。柱状上皮细胞表面多呈圆形 ,前肠、中肠柱状上皮细胞轮廓和界限清楚 ,常呈隆起状 ,而后肠上皮细胞表面较平坦。前肠柱状上皮细胞游离面的微绒毛长而密 ,后肠的短而稀疏。前肠的杯状细胞常常有较大的分泌孔 ,周围有分泌物 ,粘膜表面有粗大的分泌颗粒 ;后肠杯状细胞的分泌孔较小 ,粘膜表面有较多细小分泌颗粒。  相似文献   

11.
The effects of varying intensities of histamine stimulation on cells of the western newt fundic stomach epithelium have been studied. Oxyntic, mucous neck and surface mucous cells all secrete. In the oxyntic cell, the main effects are a movement of zymogen granules toward the apex, the discharge of their contents into the lumen and, eventually, their disappearance from the cytoplasm. Additionally, the tubular membrane elements (tubulo- vesicles) fuse with the apical plasma membrane with a corresponding reduction in their numbers and an increase in microvilli, which eventually are so numerous as to virtually occlude the lumina of gastric glands. Total histamine stimulation results in apparent damage to the oxyntic cells. Mucous neck and surface mucous cells release their mucigen droplets by exocytosis and are grossly changed in appearance also.  相似文献   

12.
The histomorphological aspects as well as the histochemical content and distribution of glycoproteins (GPs) in the mucosa of the digestive tract of the white croaker Micropogonias furnieri were studied. The buccopharyngeal cavity and the esophagous showed a squamous stratified epithelium with mucous cells. The stomach presented three portions: cardias, fundus and pylorus. Tubular glands formed by a single type of gland cell were located along the cardias and fundus. Histochemical tests showed that the buccopharyngeal cavity and the esophagous presented the largest amount of the different types of mucosubstances. Both organs showed abundant secretory mucous cells that synthesize large quantities of neutral, sulphated and sialylated GPs. The surface epithelium in the cardias and fundus synthesized and secreted scarce sialylated and neutral GPs whereas the secretions of the apical surface were abundant. The pylorus secreted large amounts of neutral as well as sulphated and sialylated GPs. Gland cells secreted neutral GPs. The ultrastructural features of the gut cells were quite similar to those of other teleosts. The buccopharyngeal cavity and the esophagous surface epithelial cells, identified by their superficial localization, were characterized by cytoplasmic vesicles of different size. Abundant goblet cells with secretory mucous granules were also present. Gastric glands in the stomach contained just one form of cell with a fine structure similar to cells that secrete pepsinogen.  相似文献   

13.
The secretory units and duct system of the echidna sublingual glands exhibit subtle architectural modifications to accommodate the viscous secretion produced by these glands. The glands are compound tubular glands, the secretory units of which are elongate with open lumina and consist only of mucous cells. Closely packed spindle-shaped myoepithelial cells invest the secretory units, but are absent around the ducts. The branched secretory tubules open into an abbreviated duct system characterized by wide lumina. Striated ducts normally associated with the second portion of the intralobular duct system are absent. The duct system shows the most obvious modification of general salivary gland architecture presumably to accommodate the viscous secretion propelled from the secretory units by surrounding myoepithelial cells.  相似文献   

14.
The proximal and interlobular ducts of rabbit zygomatic glands show a particular morphological feature consisting of numerous secretory granules localized in the apical cytoplasm of the cells. It is suggested that there is a similarity between these ducts and the granular ducts of submandibular glands in rodents.  相似文献   

15.
16.
In the present study, we firstly demonstrated immunohistochemical expressions of secretory carbonic anhydrase (CA-VI) isozyme in bovine forestomach, large intestine and major salivary glands. CA-VI was detected in basal layer epithelial cells of esophageal and forestomach stratified epithelium, in mucous cells of upper glandular region of large intestine, in serous acinar cells of the parotid gland, in serous demilune cells and some ductal liner cells of mandibular, monostomatic sublingual and esophageal glands. These immunohistolocalizations suggested that bovine CA-VI plays various roles in pH regulation, maintenance of ion and fluid balance, and cell proliferation.  相似文献   

17.
The present study was aimed at elucidating the histogenesis of parotid gland of buffalo. The study was carried out on buffalo foetuses (n = 36), during different stages of prenatal life. The foetuses were categorised into three groups based on their curved crown rump length (CVRL). The primordial anlage of parotid salivary gland was evident at 40th day of development whereas the primary ducts, in the form of cords, were first observed at 81st day of prenatal life. The capsule formation as well as the lobulation of the gland was initiated at 127th day. At 141st day, the duct system of gland was completed. The terminal tubules attained the structure of acini at 167th day. The myoepithelial cells first appeared as flattened basal cells initially around the developing acinar cells at 167th day. The typical compound tubulo-acinar nature of the gland was first observed at 185th day. Purely serous acinar cells were seen from 185th day onwards. The micrometrical studies revealed that the mean diameter of acinar cells, intercalated ducts, striated ducts and large ducts increased with the advancement of age. The serous acinar cells were devoid of acidic as well as neutral mucopolysaccharides in prenatal age groups; however, large ducts with goblet cells exhibited positive reaction. Combined PAS-AB method revealed mixed reaction in acinar cells as well as in large ducts. Fine lipid droplets were observed in intralobular as well as interlobular connective tissue; however, phospholipids were observed in the cell membrane of secretory cells and ducts.  相似文献   

18.
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   

19.
20.
The morphology of the pancreatic duct system did not receive much attention as compared to the microanatomy of the exocrine and endocrine pancreas. The histological peculiarities of the excretory duct system are of major importance especially in laboratory animals like guinea pigs. The paper describes the histological peculiarities of the major interlobular and extrapancreatic ducts in guinea pigs. The pancreatic tissue samples were collected from five guinea pigs. For histological investigation, several pancreatic fragments underwent fixation in 10% buffered formalin and were later processed by the standard paraffin technique. Subsequentially, tissue sections were stained by Goldner's trichrome staining. The mucous substances were assessed by Alcian blue and Periodic acid–Schiff staining methods. The interlobular and main pancreatic ducts in the guinea pig present a simple columnar epithelium surrounded by a thick layer of dense connective tissue. The aforementioned epithelium of the main pancreatic ducts includes principal cells, goblet cells and basal cells. Additionally, the ductal epithelium presents occasional unicellular multiloculated intraepithelial mucous glands and prominent extraepithelial glands. The latter adopts a simple or compound tubular feature. The mucus elaborated by the three glandular types is mostly neutral in goblet cells, predominantly acidic in extraepithelial ductal glands, and a similar amount of acidic and neutral mucin in intraepithelial glands. In conclusion, the epithelium-associated mucous glands in the interlobular and main pancreatic ducts in the guinea pig are restricted not only to goblet cells. A substantial mucous discharge probably with a protecting role against irritative pancreatic juice derives from the main ductal intraepithelial and extraepithelial glands.  相似文献   

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