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Mucous Cells (mucous + cell)

Distribution by Scientific Domains

Life Sciences	52%
Earth and Environmental Science	28%
Medical Sciences	16%

Selected Abstracts

EP1 and EP4 Receptors Mediate Exocytosis Evoked by Prostaglandin E2 in Guinea-Pig Antral Mucous Cells

EXPERIMENTAL PHYSIOLOGY, Issue 4 2001
Atsuko Ohnishi
Effects of prostaglandin E2 (PGE2) on exocytosis of mucin were studied in mucous cells isolated from guinea-pig antrum using video-microscopy. Stimulation with PGE2 elicited a sustained increase in the frequency of exocytotic events in a dose-dependent manner, which was under regulation by both Ca2+ and cAMP. Stimulation with a selective prostanoid EP4 receptor agonist (ONO-AEI-329, 10 ,M), which activates cAMP signals, elicited a sustained increase in the frequency of exocytotic events (30% of that evoked by 1 ,M PGE2). Stimulation with an EP1 agonist (17-P-T-PGE2, 1 ,M), which activates Ca2+ signals, increased the frequency of exocytotic events to a lesser extent (5% of that evoked by 1 ,M PGE2), while addition of an EP1 antagonist (ONO-8713, 10 ,M) decreased the frequency of exocytotic events (approximately 40% of that evoked by 1 ,M PGE2). However, addition of the EP1 agonist potentiated the frequency of exocytotic events evoked by the EP4 agonist or forskolin (which elevates cAMP levels) and increased the sensitivity of the exocytotic events to forskolin. These results suggest that the Ca2+ signal activated via the EP1 receptor potentiates the cAMP-regulated exocytotic events activated via the EP4 receptor during PGE2 stimulation, by increasing the sensitivity of the exocytotic response to cAMP. In conclusion, exocytotic events in PGE2 -stimulated antral mucous cells were regulated by interactions between EP1 and EP4 receptors. [source]

Mucous Cells in Micropogonias furnieri gills: Histochemistry and Ultrastructure

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2001
A. O. Díaz
The characteristics of the mucous cells located in the gills of the fish Micropogonias furnieri were investigated. Using histochemical procedures that included methods for localization and characterization of glycoproteins (GPs), no differences were detected between the mucous cell contents of the primary and secondary lamellae. The GPs were identified with (a) oxidizable vecinal diols; (b) sialic acids and some of their chain variants, C7 or C9; (c) carboxyl groups and (d) sulphate groups. The electron microscope showed large mucous globules of different electro densities from mucous cells located deep in the epithelium between the other epithelial cells; the release of mucus by exocytosis was observed. GPs secreted on the surface of the mucous cells was suggested to be important for the lubrication, protection and inhibition of micro-organisms. It is possibility that GPs could have similar roles in Micropogonias furnieri gills. [source]

Study of Epidermis Development in Sturgeon (Acipenser persicus) Larvae

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 5 2010
Z. Saadatfar
With 10 figures Summary Fish skin is essential for survival, maintenance of body shape, and protection against the shock and infection. During week 1 of sturgeon larval development, the epidermis is thin and not differentiated in various layers yet, but by week 4,6 the thickness increases and various layers appear, depending upon the region of the body. Mucous cells differentiate early in development on the surface of epithelium and contain acid and neutral mucopolysaccharides. Primordial sensory buds are visible within the epithelia of the skin of the head in week 1 larvae, and become numerous during later larval development. Club cells are specialized epidermal cells that have an immune function and appear in the middle layer of the head and trunk epidermis on week 4. [source]

Microscopic structure of the sperm storage tubules in the polygynandrous alpine accentor, Prunella collaris (Aves)

ACTA ZOOLOGICA, Issue 4 2001
Akira Chiba
Abstract We describe the microscopic structure of the sperm storage tubules (SSTs) of the polygynandrous alpine accentor, Prunella collaris. The SSTs were found at the utero-vaginal junction of the oviduct and were composed of a single layer of columnar epithelium. The cells of the tubule proper were non-ciliated and had a round or oval nucleus in their basal portion. Their cytoplasm was finely or coarsely vacuolated due to lipid inclusions. Under the electron microscope, the epithelial cells exhibited a number of mitochondria, Golgi bodies, occasional lysosome-like dense bodies, granular endoplasmic reticula, junctional complex, and tonofilaments. The apical margin of the cells was fringed with numerous microvilli. The epithelial lining of the SSTs was devoid of mucous cells, but showed occasional infiltration of lymphoid cells. No contractile elements were found in association with the SSTs, but a close apposition of unmyelinated nerve fibres to the basal part of the SST cells was recognized. Intraluminal sperm were arranged in bundles, and their heads were orientated towards the distal portion of the SSTs. Evidence for engulfment of sperm by the SST cells was obtained for the first time. A sign of atrophy or regression of the SSTs was found in one specimen. [source]

Ultrastructural localization of salivary mucins MUC5B and MUC7 in human labial glands

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 1 2010
Monica Piras
Piras M, Hand AR, Tore G, Ledda GP, Piludu M. Ultrastructural localization of salivary mucins MUC5B and MUC7 in human labial glands. Eur J Oral Sci 2010; 118: 14,18. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci As a result of their presence throughout the mouth in the submucosa or between muscle fibers, minor salivary glands secrete directly and continuously into the oral cavity, providing mucosal surfaces with highly glycosylated proteins that are active in bacterial aggregation and in oral tissue lubrication. In this study, we investigated the ultrastructural localization of the MUC5B and MUC7 mucins in human labial glands by means of a postembedding immunogold technique. Thin sections of normal human labial glands, obtained during surgery, were incubated with polyclonal antibodies to human salivary mucins MUC5B and MUC7, and then with gold-labeled secondary antibodies. Specific MUC5B reactivity was found in the secretory granules of mucous cells of all glands examined, and was associated with the luminal membrane of duct cells. MUC7 labeling was observed in the granules of both mucous and seromucous secretory cells of the glandular parenchyma. Quantitative analyses demonstrated that seromucous granules have higher immunogold labeling densities for MUC7 than mucous granules. Our immunohistochemical data extend the results of previous light microscopic studies of MUC5B and MUC7 localizations, pointing out the significant contribution of human labial glands in the secretion process of these two mucins. [source]

Enhancement of Ca2+ -regulated exocytosis by indomethacin in guinea-pig antral mucous cells: arachidonic acid accumulation

EXPERIMENTAL PHYSIOLOGY, Issue 1 2006
Shoko Fujiwara
Ca2+ -regulated exocytosis is enhanced by an autocrine mechanism via the PGE2,cAMP pathway in antral mucous cells of guinea-pigs. The inhibition of the PGE2,cAMP pathway by H-89 (an inhibitor of protein kinase A, PKA) or aspirin (ASA, an inhibitor of cyclo-oxygenase, COX) decreased the frequency of ACh-stimulated exocytotic events by 60%. Indomethacin (IDM, an inhibitor of COX), however, decreased the frequency of ACh-stimulated exocytotic events only by 30%. Moreover, IDM increased the frequency of ACh-stimulated exocytotic events by 50% in H-89-treated or ASA-treated cells. IDM inhibits the synthesis of Prostaglandin (PGG/H) and (15R)-15-hydroxy-5,8,11 cis-13-trans-eicosatetraenoic acid (15R-HPETE), while ASA inhibits only the synthesis of PGG/H. Thus, IDM may accumulate arachidonic acid (AA). AACOCF3 or N -(p -amylcinnamoyl) anthranilic acid (ACA; both inhibitors of phospholipase A2, PLA2), which inhibits AA synthesis, decreased the frequency of ACh-stimulated exocytotic events by 60%. IDM, however, did not increase the frequency in AACOCF3 -treated cells. AA increased the frequency of ACh-stimulated exocytotic events in AACOCF3 - or ASA-treated cells, similar to IDM in ASA- and H-89-treated cells. Moreover, in the presence of AA, IDM did not increase the frequency of ACh-stimulated exocytotic events in ASA-treated cells. The PGE2 release from antral mucosa indicates that inhibition of PLA2 by ACA inhibits the AA accumulation in unstimulated and ACh-stimulated antral mucosa. The dose,response study of AA and IDM demonstrated that the concentration of intracellular AA accumulated by IDM is less than 100 nm. In conclusion, IDM modulates the ACh-stimulated exocytosis via AA accumulation in antral mucous cells. [source]

EP1 and EP4 Receptors Mediate Exocytosis Evoked by Prostaglandin E2 in Guinea-Pig Antral Mucous Cells

Mapping of the 45M1 epitope to the C-terminal cysteine-rich part of the human MUC5AC mucin

FEBS JOURNAL, Issue 3 2008
Martin E. Lidell
Mucins are large glycoproteins protecting mucosal surfaces throughout the body. Their expressions are tissue-specific, but in disease states such as cystic fibrosis, inflammation and cancer, this specificity can be disturbed. MUC5AC is normally expressed in the mucous cells of the epithelia lining the stomach and the trachea, where it constitutes a major component of the gastric and respiratory mucus. A number of mAbs have been raised against the gastric M1 antigen, an early marker for colonic carcinogenesis. Several of these mAbs recognize epitopes present on MUC5AC, suggesting that MUC5AC is the antigen. However, some of the mAbs raised against the gastric M1 antigen are widely used as antibodies against MUC5AC, despite the fact that their specificity for MUC5AC has not been clearly shown. In this study, we have tested the reactivity of the latter antibodies against a recombinantly expressed C-terminal cysteine-rich part of human MUC5AC. We demonstrate for the first time that the widely used mAb 45M1, as well as 2-12M1 and 166M1, are true antibodies against MUC5AC, with epitopes located in the C-terminal cysteine-rich part of the mucin. [source]

High salt diets dose-dependently promote gastric chemical carcinogenesis in Helicobacter pylori -infected Mongolian gerbils associated with a shift in mucin production from glandular to surface mucous cells

INTERNATIONAL JOURNAL OF CANCER, Issue 7 2006
Sosuke Kato
Abstract Intake of salt and salty food is known as a risk factor for gastric carcinogenesis. To examine the dose-dependence and the mechanisms underlying enhancing effects, Mongolian gerbils were treated with N -methyl- N -nitrosourea (MNU), Helicobacter pylori and food containing various concentrations of salt, and were sacrificed after 50 weeks. Among gerbils treated with MNU and H. pylori, the incidences of glandular stomach cancers were 15% in the normal diet group and 33%, 36% and 63% in the 2.5%, 5% and 10% NaCl diet groups, showing dose-dependent increase (p < 0.01). Intermittent intragastric injection of saturated NaCl solution, in contrast, did not promote gastric carcinogenesis. In gerbils infected with H. pylori, a high salt diet was associated with elevation of anti- H. pylori antibody titers, serum gastrin levels and inflammatory cell infiltration in a dose-dependent fashion. Ten percent NaCl diet upregulated the amount of surface mucous cell mucin (p < 0.05), suitable for H. pylori colonization, despite no increment of MUC5AC mRNA, while H. pylori infection itself had an opposing effect, stimulating transcription of MUC6 and increasing the amount of gland mucous cell mucin (GMCM). High salt diet, in turn, decreased the amount of GMCM, which acts against H. pylori infection. In conclusion, the present study demonstrated dose-dependent enhancing effects of salt in gastric chemical carcinogenesis in H. pylori -infected Mongolian gerbils associated with alteration of the mucous microenvironment. Reduction of salt intake could thus be one of the most important chemopreventive methods for human gastric carcinogenesis. © 2006 Wiley-Liss, Inc. [source]

Ultrastructural and histochemical study on gills and skin of the Senegal sole, Solea senegalensis

JOURNAL OF APPLIED ICHTHYOLOGY, Issue 6 2004
J. M. Arellano
Summary This study was undertaken to identify the normal ultrastructural features of gills and skin of the Senegal sole, Solea senegalensis, for a comparative measure to morphological alterations caused by environmental stressors such as reduced water quality and diseases. In the Senegal sole skin, four morphologically distinct layers were identified: cuticle, epidermis, dermis and hypodermis. The epidermis was composed of stratified epithelium containing three cellular layers: the outermost or mucosa layer, the middle or fusiform layer and the stratum germinativum or the basal layer. In the mucosa, two mucous cell types were differentiated: type A cells containing several round vesicles of different electron density and type B cells containing mucosomes of uniform electron density. Senegal sole have five pairs of gill arches, each containing two rows of well-developed and compactly organized primary filaments and secondary lamellae. Fingerprint-like microridges were observed on the surface of epithelial cells. The branchial lamellae epithelium consisted of different cell types: pavement, mucous and chloride. Between the chloride cells and the larger pavement cells, accessory cells were observed. Complexes of tight junctions and desmosomes were frequently observed between adjacent chloride and epithelial cells. Neutral mucosubstances and/or glycoconjugates were observed in the epidermis, dermis and hypodermis of S. senegalensis skin. Proteins rich in different amino acids, such as arginine and cysteine, reacted negatively or weakly positive in the epidermis, dermis and hypodermis. In gills, some mucous cells responded weakly positive to periodic acid-Schiff (PAS) reaction but were strongly stained with Alcian Blue at pH 0.5, 1 and 2.5. When Alcian Blue pH 2.5,PAS reaction was performed, most mucous cells were stained blue (carboxylated mucins) and some mucocytes stained purple, indicating a combination of neutral and acid mucins. Proteins rich in cysteine-bound sulphydryl (-SH-) and cystine disulphide (-S-S-) groups were strongly detected in branchial and epidermal mucous cells, whereas lysine, tyrosine and arginine containing proteins showed very weak staining in both epidermal and branchial mucous cells. Protein reactions were strongly positive in the pillar cells, except for those rich in tryptophan, whereas the branchial cartilaginous tissue did not show an important reaction. The performed lipid reactions were negative in goblet and chloride cells. It is concluded from this study that ultrastructural and cytohistochemical features of the Senegal sole skin and gills may serve as control structures in both natural and aquaculture systems to monitor or detect environmental stress responses at the histological level. [source]

Sulphur, thiols, and disulphides in the fish epidermis, with remarks on keratinization

JOURNAL OF FISH BIOLOGY, Issue 4 2007
W. Meyer
Energy dispersive x-ray (EDX) analysis and qualitative and quantitative histochemistry were applied to study the distribution and contents of sulphur, thiols and disulphides in the epidermis of the river lamprey Lampetra fluviatilis, the lesser spotted dogfish Scyliorhinus canicula and the brown trout Salmo trutta fario. Thiols generally reacted weakly throughout the entire epidermis, whereas disulphide reactions were more distinct and differentiated. In the river lamprey, the concentrations of -S-S- groups clearly increased in the developing mucous cells from the stratum basale to the stratum superficiale; skein cells and granular cells reacted negatively to weakly. In the lesser spotted dogfish, amounts of disulphides appeared at moderate concentrations, and only goblet cells displayed a strong reaction. In the brown trout, filament cells showed low concentrations or weak reactions of disulphides, goblet cells and the most outer superficial cells stained strongly. Sulphur distribution and contents generally supported the histochemical observations in normal epidermis cells (absolute sulphur contents: 41,59 mM), only the brown trout showed high amounts of sulphur in the stratum basale (81 mM). The findings corroborate the view that there is an inverse correlation between keratinization and mucous secretion in normal fish epidermis. The sometimes distinct contents of disulphides in the outer mucous layer indicate that this system could endure higher mechanical stress than predictable from its large amounts of neutral glycoproteins. [source]

The ontogeny of the alimentary tract of larval pandora, Pagellus erythrinus L.

JOURNAL OF FISH BIOLOGY, Issue 2004
V. Micale
The ontogenesis of the alimentary tract and its associated structures (liver, pancreas, gall bladder) was studied in common pandora Pagellus eythrinus L., a promising species for diversification in Mediterranean aquaculture. Mass production of pandora has been limited so far by high larval and juvenile mortalities, which appear to be related to nutritional deficiencies. The development of the larval digestive system was studied histologically from hatching (0 DAH) until day 50 (50 DAH) in reared specimens, obtained by natural spawning from a broodstock adapted to captivity. At first feeding (3,4 DAH) both the mouth and anus had opened and the digestive tract was differentiated in four portions: buccopharynx, oesophagus, incipient stomach and intestine. The pancreas, liver and gall bladder were also differentiated at this stage. Soon after the commencement of exogenous feeding (5,6 DAH), the anterior intestinal epithelium showed large vacuoles indicating the capacity for absorption of lipids, whereas acidophilic supranuclear inclusions indicating protein absorption were observed in the posterior intestinal epithelium. Both the bile and main pancreatic ducts had opened in the anterior intestine, just after the pyloric sphincter, at this stage. Intestinal coiling was apparent since 4 DAH, while mucosal folding began at 10 DAH. Scattered mucous cells occurred in the oral cavity and the intestine, while they were largely diffused in the oesophagus. Gastric glands and pyloric caeca were firstly observed at 28 DAH and appeared well developed by 41 DAH, indicating the transition from larval to juvenile stage and the acquisition of an adult mode of digestion. [source]

Skin-type antifreeze protein expression in integumental cells of larval winter flounder

JOURNAL OF FISH BIOLOGY, Issue 6 2002
H. M. Murray
Wholemount in situ hybridization using an antisense riboprobe complementary to a winter flounder Pleuronectes americanus skin-type antifreeze protein mRNA (WFp9) and immuno histochemistry using polyclonal antibodies to the corresponding protein detected cells expressing this gene in larval winter flounder integument. Immunohistochemistry revealed two distinct populations of cells. One population extended laterally along the length of the fish and was detectable using in situ hybridization. Staining in these cells declined following yolk-sac absorption suggesting that expression was only important here during early larval development. The polyclonal antibody for skin-type antifreeze protein also reacted with another population of cells scattered throughout the integument. These cells stained with alcian blue suggesting that they were integumental mucous cells. In situ hybridization using the above probe was not able to detect the corresponding transcript within the same cells. This suggests that another gene may be involved in the production of a similar protein in this case. These data suggest that two distinct populations of cells within the larval integument are involved in skin-type antifreeze protein expression and possibly involve the activity of at least two different genes. [source]

Host response to the chondracanthid copepod Chondracanthus goldsmidi, a gill parasite of the striped trumpeter, Latris lineata (Forster), in Tasmania

JOURNAL OF FISH DISEASES, Issue 3 2010
M Andrews
Abstract The chondracanthid copepod, Chondracanthus goldsmidi is an ectoparasite of gills, inner opercula and nasal cavities of cultured striped trumpeter, Latris lineata (Forster). Whilst often present in high numbers (up to 60 parasites per host), little is known about its effect on striped trumpeter. In this study C. goldsmidi was associated with extensive epithelial hyperplasia and necrosis. Pathological changes were most pronounced near the parasite's attachment site, with papilloma-like growths surrounding the entire parasite resulting in deformation of the filament. The number of mucous cells increased near the parasite attachment sites on both the opercula and gills. Mast cells were absent in healthy gills; in contrast numerous mast cells were identified in the papilloma-like growths. Immunostaining identified piscidin-positive mast cells in the papilloma-like growths, presenting the first evidence of piscidin in the family Latridae. [source]

Development of proliferative kidney disease in rainbow trout, Oncorhynchus mykiss (Walbaum), following short-term exposure to Tetracapsula bryosalmonae infected bryozoans

JOURNAL OF FISH DISEASES, Issue 8 2002
M Longshaw
The initial site of infection in the fish host for Tetracapsula bryosalmonae, causative agent of proliferative kidney disease (PKD) is poorly understood. Following the recent recognition that freshwater bryozoans harbour the infective stages to salmonid fish, experimental transmission studies were undertaken to investigate (1) the route of entry of the parasite into the fish host and (2) the minimum exposure time required to induce clinical signs of PKD. In-situ hybridization (ISH) studies were carried out on naïve rainbow trout exposed to the naturally infected bryozoan Fredericella sultana for up to 90 min. The sporoplasm of T. bryosalmonae was detected entering the fish via mucous cells in the skin epithelium within the first minute of exposure. In addition, T. bryosalmonae cells were infrequently detected in the skeletal musculature of exposed experimental fish up to 72 h post-exposure. The route of migration through the fish to the kidney and spleen was not determined. All fish exposed to infected, disrupted bryozoans for 10, 30 and 90 min and maintained for up to 8 weeks developed clinical PKD. [source]

Observations on the histochemistry and ultrastructure of regenerating caudal epidermis of the tuatara Sphenodon punctatus (Sphenodontida, Lepidosauria, Reptilia)

JOURNAL OF MORPHOLOGY, Issue 2 2003
Lorenzo Alibardi
Abstract Study of the histology, histochemistry, and fine structure of caudal epidermal regeneration in Sphenodon punctatus through restoration of a scaled form reveals that the processes involved resemble those known in lizards. Following establishment of a wound epithelium (WE), subjacent scale neogenesis involves epidermal downgrowths into the dermis. Although the process is extremely slow, and most new scales do not overlap, their epidermal coverings reestablish epidermal generation (EG) formation. As in lizards, the flat, ,-keratogenic, WE cells contain lipids as revealed by their affinity for Sudan III. A few mucous cells that store large PAS-positive mucus-like granules also occur in WE. During differentiation of WE cells, among the bundles of 70-nm tonofilaments are many lamellar bodies (LBs) and mucous granules (MGs) that discharge their contents into the cytoplasm and extracellular spaces producing a strongly PAS-positive keratinized tissue. Richness of epidermal lipids coexistent with mucus is a primitive characteristic for amniote vertebrates, probably related to functions as a barrier to cutaneous water loss (CWL). As scale neogenesis begins, beneath the superficial WE appear 3,5 layers of irregularly shaped cells. These contain tonofilament bundles surrounded by small, round keratohyalin-like granules (KHLGs) and a keratinized matrix with ,-keratin packets and a 3,5-nm thick keratin granulation. This mixture of ,- and ,-keratogenic capacities resembles that seen in the innermost cells of a normal tuatara epidermal generation. As in the latter, but in contrast to both normal and regenerating lizard epidermis, no definable shedding complex with interdigitating clear layer and oberhautchen cells occurs (Alibardi and Maderson, 2003). The tortuous boundaries, and merging ,-keratin packets, identify subjacent keratinizing cells as precursors of the typical stratified, squamous ,-layer seen in long-term regenerated caudal skin wherein the entire vertical sequence of epidermal layers resembles that of normal scales. The sequence of events in caudal epidermal regeneration in S. punctatus resembles that documented for lizards. Observed differences between posttrauma scale neogenesis and scale embryogenesis are responses to functional problems involved in, respectively, restoring, or forming, a barrier to CWL while accommodating rapid somatic growth. J. Morphol. 256:134,145, 2003. © 2003 Wiley-Liss, Inc. [source]

Nerve growth factor localization in the nasal mucosa of patients with persistent allergic rhinitis

ALLERGY, Issue 1 2009
M. Bresciani
Background and objectives:, Nerve growth factor (NGF) and NGF receptors have been shown to be expressed by structural and infiltrating inflammatory cells in the human allergic bronchial mucosa and conjunctiva. In the nose, a positive immunostaining for NGF was recently reported in biopsies of subjects undergoing surgery for refractory nasal obstruction. This study was aimed at studying by immunohistochemistry NGF expression and localization in the nasal mucosa from subjects with moderate/severe persistent allergic rhinitis and natural allergen exposure. Methods:, Immunostaining for NGF, tryptase and eosinophil cationic protein was performed in human nasal turbinate sections of 25 patients affected by persistent allergic rhinitis and sensitization to Dermatophagoides pteronyssinus. Results:, NGF was consistently expressed in the epithelium and in the submucosa of allergic rhinitic subjects, preferentially localized in eosinophils and mast cells. A strong NGF immunostaining was found in mucous cells of the epithelial lining and in the submucosal glands. Conclusions:, As previously shown for allergic asthma and allergic conjunctivitis, NGF is also detectable in the nasal mucosa of patients with persistent allergic rhinitis. The preferential NGF localization in mucous cells of the epithelial lining and in the submucosal glands suggests a possible role for NGF in modulating secretion in allergic rhinitis and possibly other allergic diseases. [source]

Histology and Mucin Histochemistry of The Digestive Tract of Yellow Catfish, Pelteobagrus fulvidraco

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2009
X. J. Cao
Summary The histology and characteristics of mucins secreted by epithelial mucous cells of the digestive tract in yellow catfish, Pelteobagrus fulvidraco were investigated using light microscope and transmission electron microscope. The digestive tract was divided into a pharynx, oesophagus, U-shaped stomach (with a cardiac, fundic and pyloric part) and intestine, composed of anterior intestine, middle intestine and posterior intestine, which consisted of a mucosa (epithelial layer), lamina propria-submucosa, muscularis and serosa. A large number of isolated longitudinal striated muscular bundles were present in the lamina propria-submucosa of pharynx. Goblet cells were observed throughout the digestive tract, except in the stomach. In the cardiac and fundic stomach, a plenty of gastric glands were observed, whereas they were absent in the pyloric part. Numerous mitochondria and endoplasmic reticulum were observed in the columnar epithelial cells of the intestine, especially of the anterior part. The epithelial mucous cells contained neutral or other two mixtures of acid and neutral mucins, the first being the most common. The neutral mucin was the only type of mucins in the stomach, anterior intestine and middle intestine. The results of this study will be helpful for understanding the digestive physiology and diagnosing some gastrointestinal diseases in yellow catfish. [source]

The Mucosa of the Digestive Tract in Micropogonias furnieri: A Light and Electron Microscope Approach

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 4 2008
A. O. Diaz
Summary 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. [source]

Ultrastructural Characterization of Gills in Juveniles of the Argentinian Silverside, Odontesthes bonariensis (Valenciennes, 1835) (Teleostei: Atheriniformes)

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2 2006
F. A. Vigliano
Summary An ultrastructural study was performed on the gills of juvenile Argentinian silverside, Odontesthes bonariensis. The gills are composed of two sets of four holobranchs and, in turn, each holobranch consists of a gill arch and two rows of caudolaterally projecting branchial filaments. From the dorsal and ventral surfaces of each filament, branchial lamellae radiate out as foldings of the epithelial layer. Gill rakers are present on each of the gill arches, on the anteromedial side of the arch opposite to the filaments. Gill rakers, gill arches and branchial filaments are covered by a stratified epithelium, whereas branchial lamellae essentially consist of a thin epithelial envelope containing capillaries. In the stratified epithelium, mucous cells, rodlet cells, granular cells, pavement epithelial cells and mitochondria-rich cells are identified. The thin epithelium that lines the lamellae comprises two cell types, outer and inner epithelial cells, and the capillary walls on the inside of the epithelial envelope are defined by pillar cells. The ultrastructure of all these cell types is described and our findings are discussed in light of the existing data on fish gill morphology. In the gills of juvenile Argentinian silverside is of particular interest the characteristics showed by mitochondria-rich cells, such as their arrangement in clusters of 2,3 cells and their small and depressed surface in contact with the aquatic milieu, features which strongly resemble those of euryhaline species. [source]

Mucous Cells in Micropogonias furnieri gills: Histochemistry and Ultrastructure

Loss of caspase-2, -6 and -7 expression in gastric cancers,

APMIS, Issue 6 2004
NAM JIN YOO
Caspases play an essential role during apoptotic cell death, and alterations of caspases are known to contribute to human cancer development. In the current study, we analyzed the expression of caspase-2, -6 and -7 in 120 gastric carcinomas by immunohistochemistry using a tissue microarray approach. Caspase-2, -6 and -7 were expressed in 42 (35%), 63 (53%) and 39 (33%) of the gastric cancers, respectively. By contrast, the surface mucous cells and mucosal glandular cells in the normal gastric mucosa showed strong immunoreactivity for caspase-2, -6 and -7. Taken together, these results indicate that caspase-2, -6 and -7 expression in gastric cancer cells is decreased compared to in normal gastric mucosal cells, and suggest that loss of caspase-2, -6 and -7 expression might be involved in the mechanisms of gastric cancer development. [source]