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1.
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   

2.
The morphology of the gland cells in the glandular sac area of the Bactrian camel and the composition of secretory substances were examined by histochemical methods. It was found that the gland cells of the glandular sac area were of the same type and size as those of the cardiac glands. The composition of secretory substances from the glandular sac area was the same as that of secretory substances from the cardiac glands. Moreover, secretory substances from the gland cells of the glandular sac area contained a great deal of acid glycoconjugates, such as sialic acid, in addition to neutral saccharides (fucose, mannose, glucose, N-acetyl-D-glucosamin, galactose and N-acetyl-galactosamin). Furthermore, immunohistochemical examination showed that progastricsin was present in the gland cells of the glandular sac area and the cardiac gland. In this study, histological analysis suggested that the stomach of the Bactrian camel is a single cavity stomach, formed as a result of multiple differentiation and growth of cardiac glands through the process of evolution.  相似文献   

3.
The poll glands of the camel are tubuloalveolar glands. They consist of lobules separated by interlobular connective tissue. Adrenergic axons and blood vessels including fenestrated capillaries are present in the intralobular connective tissue in close proximity to the secretory cells. The prominent features of the secretory cell cytoplasm are many mitochondria, smooth endoplasmic reticulum, and many vesicles in various secretory stages.
It is concluded that the secretory cells have apocrine as well as merocrine modes of secretion. The glands may have the ability to uptake hormones and concentrate them. Additional work is needed before considering these glands as steroid-secreting glands.  相似文献   

4.
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   

5.
Retrovirus-like particles were detected in venom glands from Bothrops jararacussu during electron microscopy. Type C-like particles were found inter- and intracellularly in gland and vessel lumina and scattered in the connective tissue. They were about 100 nm in diameter, with an electron dense core and bilaminar external membrane. Shapes suggestive of a budding process from the plasma membrane were also observed. Less frequently, type A-like particles, about 80 nm diameter with an electronlucent core, appeared in association with the membranes of the endoplasmic reticulum of the secretory cells.  相似文献   

6.
The morphological characteristics of myoepithelial cells and arrectores pilorum muscles were investigated in caudal, metatarsal and preorbital glands of Hokkaido sika deer (Cervus nippon yesoensis Heude, 1884) using immunohistochemistry for alpha-smooth muscle actin. In the metatarsal, preorbital and general skin glands, myoepithelial cell layers continuously embraced the secretory epithelium, while in the caudal gland, discontinuous myoepithelial cell rows surrounded the apocrine tubules. There was a trend that the widths of the myoepithelial cells of the caudal and preorbital glands appeared to be thinner than those of the metatarsal and general skin glands. In the metatarsal gland, the arrectores pilorum muscles were highly developed and considerably larger than those in other skin glands.  相似文献   

7.
The aim of this was to investigate the histology and immunohistochemistry of interstitial glands during non‐breeding season in camel ovaries. A total of 21 mature, non‐pregnant and apparently healthy camels aged between 8 and 12 years were slaughtered. The ovaries were removed within 15 min, cleaned from adipose tissue, weighted and examined grossly. The histological preparation was made, and then, the blocks were cut at 3–5 microns thickness and stained by H&E for histological examinations. Moreover, some sections were stained with Sudan Black for lipid detection. Immunohistochemical analysis of paraffin‐embedded ovarian tissues was performed to detect the localization of S‐100, vimentin, progesterone receptors (PR) and oestrogen receptors (ER). Immunoreactive signals were detected using UltraVision Detection System. The results revealed that the interstitial glands were located in the cortical region and they were arranged in various arrangements either single, in couple or in groups rich in lipid droplet. All interstitial gland arrangements were enclosed by connective tissue capsules containing fibroblasts and collagenous fibres separated them from the surrounding ovarian structures. Both interstitial glands and their surrounding CT were penetrated by several blood vessels. There was a strong immunoreactive signal for S‐100 in the nuclei of interstitial cells, and no signals were detected either in cells of the interstitial glands or their connective tissue with PR. We could conclude that the interstitial gland is distinct in ovary of camel and further studies are needed to elucidate its rule in steroid synthesis.  相似文献   

8.
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   

9.
The distribution and morphology of the cornual, sub-caudal, mental and preputial glands were studied macro- and microscopically in four Toggenburg and eight miniature male goats. Although the cornual and sub-caudal glands could be readily located macroscopically, the mental glands in the inter-mandibular region and the preputial glands at the preputial orifice were not visible macroscopically. On histological section, all glands were found to be composed of lobulated sebaceous tissue combining both normal and modified holocrine secretory units. Over a period of 18 months, five consecutive glandular swabs for scent tests were taken to assess the influence of age and season on buck odour production. Buck odour was most apparent in the cornual gland area, less distinct at the mental gland region, and faint or absent in the other glandular areas. Surgical removal of the cornual glands caused a decrease in buck odour and persisting scent was ascribed to smaller skin glands dispersed in the cranial body half. Complete absence of buck odour was only observed in castrated bucks.  相似文献   

10.
In this study, we conducted a light microscopic and ultrastructural analysis of the integument of the one-humped camel (Camelus dromedarius). In general, the epidermal strata of the camel integument appeared typical of those found in non-desert mammals. Two cell populations were noted in the stratum basale: one with a flat, non-serrated base and the other with a highly serrated base. Typical fine structure was observed in keratinocytes of the stratum spinosum and stratum granulosum. The stratum corneum was six to 10 cells thick. Within the different strata, overall cell morphologies and the general distribution and relative abundance of cellular organelles appeared typical. Dermal features included the presence of myoepithelial cells surrounding apocrine tubular glands. Inter- or intracellular canaliculi within the secretory cells of the apocrine glands, reported to be present in certain other non-desert mammals, were not evident in the camel. Together, these data indicate that while the camel is clearly adapted for a desert lifestyle, these adaptations do not include significant specializations at the cellular or subcellular level in the integument.  相似文献   

11.
The perineal glands were identified in the zona cutanea of the anal canal of males more than 4 months old. These glands are organized on a lobular model made up of sebaceous cells and isolated by connective parietal cells. The paler in colour the sebaceous cells, the more lipid vacuoles they contain. PAS-negative and Sudan III-positive secretions were demonstrated in these cells. Electron microscopy showed that the intracellular organelles were well-developed, which is a mark of high metabolic activity and storage by the glandular cells. Cystic vesicles were found in the lobules. The size and number of these cysts were variable. The position of the cyst cells and the variability of their size suggest that they are formed after lysis of some holocrine secretory cells. These observations suggest a progressive maturation of the gland towards its secretory site. No specific secretory duct for the purpose of draining secretions was observed, however, there were possible discharge pathways, although with no real walls, as is found for the biliary canaliculi.  相似文献   

12.
The immunohistochemical expression of the smooth muscle-specific protein calponin was studied to assess the contribution of myoepithelial cells to the histogenesis of spindle cells of complex and mixed tumors of the mammary gland of the dog and the origin of cartilage and bone in mixed tumors. Formalin-fixed tissues from 55 benign and malignant tumors (49 also containing surrounding normal mammary gland) were evaluated. Periacinar and periductal myoepithelial cells of all the 49 normal mammary glands were diffusely stained by the anti-human calponin monoclonal antibody. Calponin was found in 53 (98%) of the tumors studied, reacting with the myoepithelium-like cells of 86% of benign tumors and their remnants in 85% of malignant tumors. Five different types of calponin-immunoreactive myoepithelial cells were identified: hypertrophic myoepithelial cells. fusiform cells, stellate myoepithelial cells, rounded (myoepithelial) cells, and chondroblasts. Differences in staining intensity and staining pattern among these five types of cells suggested a transition of myoepithelial cells to chondroblasts. Stromal myofibroblasts also showed calponin immunoreactivity, but they did not react with a cytokeratin 14 monoclonal antibody, which recognizes myoepithelial cells in mammary gland. Calponin appears to be a very sensitive marker of normal and neoplastic myoepithelium in the canine mammary gland, and its identification in different cell types of complex and mixed tumors of the mammary gland of the dog suggests a major histogenetic role for myoepithelial cells.  相似文献   

13.
To compare the roles of chondromodulin-I (ChM-I) and bone morphogenetic protein-6 (BMP-6) in ectopic mesenchymal tissue formation in canine mammary gland tumors, 33 tumors and 2 normal mammary glands were examined. Immunohistochemical analysis revealed co-expression of ChM-I and BMP-6 in canine mammary tumors. In mixed tumors, newly formed woven bone with ossified cartilage matrix was observed in 4/9 cases. The osteoblasts lining the woven bone showed moderate immunoreactivity to ChM-I and BMP-6. Almost all chondrocytes and proliferative myoepithelial cells within the basement membrane showed intense immunoreactivity to both, and the myoepithelial cells adjacent to the mature cartilage showed the most intense immunoreactivity. The immunoreactivity to ChM-I and BMP-6 of the interstitial myoepithelial cells in the myxomatous stroma varied in each focus of mixed tumors. Similar findings were found in complex adenomas. In simple adenomas, hyperplasic myoepithelial cells within the basement membrane showed moderate immunoreactivity to both markers. Western blot analysis detected a 25 kDa band of ChM-I in fresh tissue samples from three mixed tumors. Our results support the hypothesis that proliferating myoepithelial cells with ChM-I and BMP-6 expression play important roles in mesenchymal metaplasia in canine mammary tumors.  相似文献   

14.
The expressions of cytokeratin 8 and 18 (CK8 and CK18) in the normal canine skin (2 cases) and cutaneous adnexal tumors (127 cases) were investigated immunohistochemically. In the normal skin, co-expression of CK8/18 was found in the glandular epithelium of apocrine sweat glands, and single CK8-immunoreactivity was detected occasionally in the external root sheath at the isthmus and suprabulbar regions of the hair follicles. Neoplastic glandular epithelial cells in all apocrine gland tumors (21/21 cases, 100%) had co-expression of CK8/18. In trichoblastomas (27/28 cases, 96%), most neoplastic cells were diffusely positive for CK8, but those were negative for CK18. Single CK8-expression was also observed in basaloid neoplastic cells in several cases of trichoepitheliomas (7/19 cases, 37%) and pilomatricoma (1/7 cases, 14%). In several cases of trichoblastomas (4/28 cases, 14%) and trichoepitheliomas (2/19 cases, 11%), tumor cells forming glandular structures had co-expression of CK8/18. There were no positive reactions for both CK8 and 18 in infundibular keratinizing acanthomas, and sebaceous and hepatoid gland tumors. The present findings indicate that co-expression of CK8/18 is a specific feature of apocrine sweat glands and single CK8-expression represents the natures of external root sheath or pluripotential stem cells. Thus, the combination of CK8- and 18-immunostainings may have the utility to confirm the directions of differentiation in canine cutaneous adnexal tumors providing a reliable hallmark for histopathological diagnoses.  相似文献   

15.
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   

16.
In the oesophagus, mucins, which originate from oesophageal submucosal glands, play an important role in the mucosal protection as a pre-epithelial barrier. In this study, the structure of cervical and thoracic parts of oesophagus of Japanese quail during the post-hatching period was compared, and the contents of carbohydrate and gastric mucin MUC5AC of the oesophageal glands in these parts were analysed at the light microscope levels by applying conventional histochemical and immunohistochemical methods. The oesophageal glands were present at hatching, located in the laminae propria. The numbers of glands were different in the cervical and thoracic parts, but the differences were found to be insignificant. The thoracic part has the oesophageal tonsils which are associated with the glands. Oesophageal tonsil was formed from day 5 after hatching. In quail of all ages, the secretory epithelium of glands contained neutral sialomucins and weakly sulphomucins. The cells in the neck region of secretory units contained sialomucins, while the cells of excretory ducts had strongly sulphomucins. Sialomucin containing cells in the secretory units increased with the advance of age and glandular development. But, in the secretory units, the sulphomucin content of glands was more in the thoracic part. The secretory epithelium of tonsil-associated glands contained mostly sulphomucins and a little sialomucin. From the hatching, MUC5AC mucin was detected in the cells of excretory ducts. Although the lymphoepithelium of the tonsil units exhibited negative reactions to all histochemical methods, it showed positive reaction to MUC5AC mucin antibody. In conclusion, the cervical and thoracic parts may be functionally different and the thoracic part of oesophagus was transformed into an immunological organ following day 5 after hatching.  相似文献   

17.
The carpal organ of adult female wild swine is a sweat-type gland which secretes an odorous substance. The gland consists of 5-7 lobes, each made up of lobules with convoluted glandular tubules. The gland secretion is transported in large excretory canals which empty from 5 to 7 clearly visible pores. An ultrastructural examination showed that the glandular tubules are made up of single-layered epithelium with different types of cells. One type, with rather electron-dense cytoplasm, is secretory cells full of granular material which empties into the tubule lumen. A second cell type has a glycogen-rich, transparent cytoplasm. Its role appears to be secreting a watery, electrolyte-containing liquid. In the intermediate zone of the tubules, there is a third type of cell with transparent cytoplasm. Its ultrastructural characteristics seem to indicate that its function is to reabsorb the excess watery component. In the wall of the glandular tubules, outside the epithelium, there are myoepithelial cells which facilitate the movement of the secretions toward the collector canal.  相似文献   

18.
Apoptosis has been shown to be an important regulator of endometrium function. To clarify the regulation of apoptosis in the cat endometrium during the normal oestrus cycle, the expressions of the apoptosis‐related proteins (Bcl‐2 and Bax) and their correlation to the inhibitor of apoptosis protein Survivin were analysed using immunohistochemistry. The TUNEL technique (TdT‐mediated dUTP nick end labelling) was also used to detect DNA fragmentation characteristic of apoptotic cells. The results demonstrated that TUNEL labelling is not effective for the detection of apoptosis in cat endometrium. Survivin was expressed in the luminal and glandular epithelial cells of cat endometrium during all phases of the oestrus cycle. Survivin was localized in both the cytoplasm and nuclei of superficial and deep uterine gland cells during the luteal phase, while only cytoplasmic staining was observed during the follicular and anoestrus phases. Bax immunoreactivity in the cytoplasm of luminal and glandular epithelial cells as well as the smooth muscle cells of blood vessels was weak in the anoestrus phase. Compared with anoestrus, the intensity of Bax immunostaining was moderate in the follicular phase and increased dramatically in the luteal phase. Bcl‐2 immunostaining in the cytoplasm of luminal and glandular epithelial cells was moderate in the anoestrus phase. During the early follicular phase, cytoplasmic Bcl‐2 immunostaining was detected mostly in glandular epithelial cells. In the mid‐follicular phase, in glands, the amount of Bcl‐2 protein increased progressively from the superficial to the deep layer. In contrast, the expression of Bcl‐2 decreased in the secretory phase, being very low or absent in the mid‐ and late luteal phases. The overall results suggest that Survivin, Bax and Bcl‐2 proteins may cooperatively contribute to cell apoptosis and cell proliferation in the cat uterus during the oestrus cycle.  相似文献   

19.
Adrenal glands of adult and young male mink were examined for a period of twelve months from July, 1970 and the seasonal variations in the relative widths of the cortex and medulla were investigated using histometric procedures. The medulla to cortex ratio in adult mink was noted to be increased during the months immediately following the breeding season although no consistent change was noted in the total size of the adrenal gland. Histochemical analysis using periodic acid Schiff reagent (PAS) for carbohydrates, and Oil red-0-stain for lipids revealed focal accumulations of pigment cells in the zona reticularis during the post breeding season. The presence of strands of PAS positive cells in the outer zones of adrenal cortex just before the peak of the breeding season indicates that these cells may be in the process of migration and infiltration from the zona glomerulosa to the zona reticularis where they become encased by a thin layer of connective tissue. The aggregation of PAS and Oil red-0 positive cells in the zona reticularis, previously assumed to be a response to hormone treatment, may be a normal feature associated with the onset of testicular quiescence in sexually mature mink.  相似文献   

20.
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   

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