scholarly journals THE FINE STRUCTURE OF BRUNNER'S GLANDS IN THE MOUSE

1965 ◽  
Vol 25 (3) ◽  
pp. 563-576 ◽  
Author(s):  
Daniel S. Friend
Keyword(s):  
Golgi Complex ◽  
Secretory Granules ◽  
Structural Features ◽  
Surface Epithelium ◽  
Secretory Cells ◽  
Brunner's Glands ◽  
Brunner’S Glands ◽  
Submucosal Glands ◽  
Glandular Cells ◽  
Cytological Characteristics

Examined with the electron microscope, the secretory cells of the submucosal glands of Brunner in the mouse present a curious combination of the fine-structural features of both serous and mucus-secreting cells. The cells have numerous mitochondria, abundant basal ergastoplasm, dense secretory granules that bear a superficial resemblance to pancreatic zymogen granules, and an unusually extensive Golgi apparatus. The prominence of the lamellar, vesicular, and vacuolar elements of the Golgi complex facilitates detailed observation of these components. More evident than in other glandular cells, aggregates of small vesicles appear to represent the transitional elements and are vehicles for transport of the product between the ergastoplasm and the Golgi complex. The numerous vesicular evaginations of smooth-surfaced regions on cisternae of the rough-surfaced endoplasmic reticulum and accumulations of innumerable vesicles of similar size in the area between the nearest profiles of the ergastoplasm and the Golgi complex support this contention. The cytological characteristics and physiologic properties of Brunner's glands in various species are discussed briefly. It is concluded that the submucosal glands of the mouse are excellent material for exploration of the ultrastructural correlates of both protein and carbohydrate secretion, and it is suggested that their secretion may have functions other than those generally attributed to them, namely, chemical and mechanical protection of the duodenal surface epithelium.

The Fine Structure of Brunner’s Glands in the Human

1967 ◽  
Vol 25 ◽  
pp. 66-67
Author(s):  
T. S. Lesson ◽  
C. R. Leeson
Keyword(s):  
Light And Electron Microscopy ◽  
Histological Structure ◽  
Surgical Biopsy ◽  
Brunner's Glands ◽  
Biopsy Specimens ◽  
Brunner’S Glands ◽  
Submucosal Glands ◽  
History Of ◽  
The Common ◽  
Foamy Cytoplasm

Duodenal submucosal glands occur in all mammals but show species differences both in their extent and histological structure. Surgical biopsy specimens were obtained from five individuals aged from 37 to 56 with no history of duodenal abnormality. In all cases the patient was starved for four to eight hours prior to operation and the biopsies were taken from the second part of the duodenum immediately proximal to the opening of the common bile duct. The tissue was prepared both for light and electron microscopy.By light microscopy Brunner’s glands in the human appear as masses of coiled tubules in the submucosa with ducts opening into the bases of intestinal glands. Component cells are characteristically mucous in type with dark, irregular, basally-located nuclei and clear, foamy cytoplasm.

Fine Structure of the Normal Canine Prostate

1968 ◽  
Vol 26 ◽  
pp. 168-169
Author(s):  
M. D Maser
Keyword(s):  
Secretory Granules ◽  
Single Layer ◽  
Structural Features ◽  
Three Dimensions ◽  
Secretory Cells ◽  
Cell Cytoplasm ◽  
Dark Cell ◽  
Dark Cells ◽  
Dense Cores ◽  
High Concentrations

The secretory epithelia of prostate glands of healthy dogs have varieties of organization and subcellular structure that previously have not been reported. In some acini, the secretory cells are columnar, and are aligned in a single layer (Fig. 1). The cells are of two types, “light” and “dark”, which I have been able to distinguish only on the basis of general cytoplasmic density. Other structural features of interest are: extensive lateral intercellular interdigitation; irregularly shaped, large lipid bodies, often associated with high concentrations of glycogen, and present in both the apical and basal regions of the cells; apically concentrated secretory granules, some of which are distinguished by having dense cores; prominent Golgi apparatuses, oriented both apically and laterally; extensive rough endoplasmic reticulum, some cisternae of which are distended; and nuclei which are often observed to be multi-lobular and very irregular in outline. Cells arranged in this manner have well defined tight junction complexes at their lateral apical surfaces.In most acini, however, the architecture is more complicated. Often, thin extensions of dark cell cytoplasm surround and separate adjacent light cells (Fig. 2). The dark cell cytoplasm is expanded in some areas to accomodate mitochondria, and it contains numerous ribosomal clusters and rough endoplasmic reticular cisternae. Desmosomal attachments between the light and dark cells are found commonly in the regions of envelopment. I have not yet determined whether the dark cells completely encapsulate the dark cells in three dimensions.

scholarly journals Lectin-labeled membrane is transferred to the Golgi complex in mouse pituitary cells in vivo.

1987 ◽  
Vol 35 (4) ◽  
pp. 489-498 ◽  
Author(s):  
B J Balin ◽  
R D Broadwell
Keyword(s):  
Golgi Complex ◽  
Secretory Granules ◽  
Surface Membrane ◽  
Dense Core ◽  
Secretory Cells ◽  
Pituitary Cells ◽  
Posterior Pituitary ◽  
Peroxidase Reaction ◽  
Mouse Pituitary

Labeling of the Golgi complex with the lectin conjugate wheat germ agglutinin-horseradish peroxidase (WGA-HRP), which binds to cell surface membrane and enters cells by adsorptive endocytosis, was analyzed in secretory cells of the anterior, intermediate, and posterior lobes of mouse pituitary gland in vivo. WGA-HRP was administered intravenously or by ventriculo-cisternal perfusion to control and salt-stressed mice; post-injection survival times were 30 min-24 hr. Peroxidase reaction product was identified within the extracellular clefts of anterior and posterior pituitary lobes through 24 hr but was absent in intermediate lobe. Endocytic vesicles, spherical endosomes, tubules, dense and multivesicular bodies, the trans-most saccule of the Golgi complex, and dense-core secretory granules attached or unattached to the trans Golgi saccule were peroxidase-positive in the different types of anterior pituitary cells and in perikarya of supraoptico-neurohypophyseal neurons; endoplasmic reticulum and the cis and intermediate Golgi saccules in the same cell types were consistently devoid of peroxidase reaction product. Dense-core secretory granules derived from cis and intermediate Golgi saccules in salt-stressed supraoptic perikarya likewise failed to exhibit peroxidase reaction product. The results suggest that in secretory cells of anterior and posterior pituitary lobes, WGA-HRP, initially internalized with cell surface membrane, is eventually conveyed to the trans-most Golgi saccule, in which the lectin conjugate and associated membrane are packaged in dense-core secretory granules for export and potential exocytosis of the tracer. Endoplasmic reticulum and the cis and intermediate Golgi saccules appear not to be involved in the endocytic/exocytic pathways of pituitary cells exposed to WGA-HRP.

scholarly journals Histology of the light organs of Pholas dactylus (Lamellibranchia)

1960 ◽  
Vol 39 (1) ◽  
pp. 109-115 ◽  
Author(s):  
J. A. C. Nicol
Keyword(s):  
Outer Part ◽  
Mantle Cavity ◽  
Surface Epithelium ◽  
Secretory Cells ◽  
Epithelial Surface ◽  
Secretory Cycle ◽  
Light Organs ◽  
Glandular Cells ◽  
Mucus Cells ◽  
Pyriform Cells

The piddock, Pholas dactylus L., gives off a luminous secretion when irritated. The luminous glands which produce the secretion are two longitudinal stripes in the exhalant siphon, a pair of triangular organs in the mantle cavity near the base of the siphon, and a stripe around the ventral rim of the mantle (Panceri, 1872).The histology of the light-organs has been described several times. A light-organ is covered by a simple columnar ciliated epithelium, below which are many glandular cells, which discharge through the surface epithelium. The outer part of the glandular layer consists of a mass of large mucus cells. Deeper lies a second glandular region containing large cells with long necks that extend to the external epithelial surface. Dubois (1892, 1914, 1928) believed that the photogenic tissue was made up of two kinds of secretory cells; these were the superficial ciliated cells, which possessed glandular bases (fixed secretory cells); and deeper lying glandular cells derived from clasmatocytes (migratory secretory cells). Rawitz (1891) clearly distinguished a mucous from an underlying photogenic layer. The latter, according to Förster (1914), contains pyriform cells with long necks. He believed that he could distinguish a secretory cycle in the photogenic cells. Exhausted cells at the beginning of the cycle possessed an alveolar cytoplasm; granules began to appear in the cytoplasm; the granules increased in number and stained intensely with iron haematoxylin. Those photogenic cells which were filled with granules were in the active secretory state. Transitional stages between the inactive (or depleted) cells and the active (granular) cells were rare.

scholarly journals Histogenesis of developing human fetal stomach

2021 ◽  
Vol 9 (10) ◽  
pp. 3043
Author(s):  
Rafika Munawara ◽  
Kanchan Kapoor ◽  
Mahesh K. Sharma ◽  
Poonam Goel ◽  
Poonam Chaudhary
Keyword(s):  
Secretory Granules ◽  
Physiological Activity ◽  
Gastric Gland ◽  
New Drugs ◽  
Body Region ◽  
Surface Epithelium ◽  
Gastric Glands ◽  
Aggregated Data ◽  
Microscopic Features ◽  
Glandular Cells

Background: Human stomach is a highly specialised organ with distinct types of glands and microscopic features for its physiological activity. This study aimed to assess the chronological order in the development of different layers and the cyto-differentiation of various glandular cells in 50 fetuses from 12 weeks of gestation till term.Methods: Tissue was taken from cardiac, body and pylorus to investigate with light and confocal microscopy.Results: The gastric gland formation began as an indentation of the surface epithelium, gastric pit and simultaneous development of glandular buds in the mucosa. The pyloric glands preceded the development of cardiac and gastric glands showing retro cranial sequence of development. In contrast, the muscularis externa showed the classical craniocaudal model of development with oblique layer in the cardiac region by 14 weeks and body region by 16 weeks of gestation. The parietal cells were well developed by 12 weeks and the chief cells by 16 weeks with prominent secretory granules. In addition, the pyloric sphincter was a clearly defined anatomical sphincter developed by whorling of the inner circular layer at the pyloric end of the stomach evident from 12 weeks of gestation.Conclusions: The results showed that the significant cellular morphogenesis occurred between 12-20 weeks of gestation. This aggregated data will serve as a catalyst in the understanding intricacy of embryogenesis, pathogenesis tracing of congenital anomalies and invention of new drugs.

Ultrastructural Aspects of Golgi Complex Function in Parathyroid Cells of Winter Frogs

1973 ◽  
Vol 31 ◽  
pp. 680-681
Author(s):  
William J. Dougherty
Keyword(s):  
Golgi Complex ◽  
Secretory Granules ◽  
Complex Function ◽  
Secretory Activity ◽  
Secretory Proteins ◽  
Perivascular Spaces ◽  
Pituitary Cells ◽  
Electron Microscopic ◽  
Ca Ions ◽  
Regulation Of Secretion

The regulation of secretion in exocrine and endocrine cells has long been of interest. Electron microscopic and other studies have demonstrated that secretory proteins synthesized on ribosomes are transported by the rough ER to the Golgi complex where they are concentrated into secretory granules. During active secretion, secretory granules fuse with the cell membrane, liberating and discharging their contents into the perivascular spaces. When secretory activity is suppressed in anterior pituitary cells, undischarged secretory granules may be degraded by lysosomes. In the parathyroid gland, evidence indicates that the level of blood Ca ions regulates both the production and release of parathormone. Thus, when serum Ca is low, synthesis and release of parathormone are both stimulated; when serum Ca is elevated, these processes are inhibited.

Analysis of the Anterior Secretory Cells of Onchidohs Muricata (Nudibranchia)

1981 ◽  
Vol 39 ◽  
pp. 614-615
Author(s):  
Roy Skidmore
Keyword(s):  
Endoplasmic Reticulum ◽  
Secretory Granules ◽  
Golgi Body ◽  
The Body ◽  
Secretory Cells ◽  
Secretory Vesicles ◽  
High Magnification ◽  
Large Numbers ◽  
Membrane Bound ◽  
Sole Of The Foot

The long-necked secretory cells in Onchidoris muricata are distributed in the anterior sole of the foot. These cells are interspersed among ciliated columnar and conical cells as well as short-necked secretory gland cells. The long-necked cells contribute a significant amount of mucoid materials to the slime on which the nudibranch travels. The body of these cells is found in the subepidermal tissues. A long process extends across the basal lamina and in between cells of the epidermis to the surface of the foot. The secretory granules travel along the process and their contents are expelled by exocytosis at the foot surface.The contents of the cell body include the nucleus, some endoplasmic reticulum, and an extensive Golgi body with large numbers of secretory vesicles (Fig. 1). The secretory vesicles are membrane bound and contain a fibrillar matrix. At high magnification the similarity of the contents in the Golgi saccules and the secretory vesicles becomes apparent (Fig. 2).

Scanning and Transmission Electron Microscopy of the Endometrium in Women with Ovarian Dysgenesis (Turner'S Syndrome)

1976 ◽  
Vol 34 ◽  
pp. 148-149
Author(s):  
A. González-Angulo ◽  
S. Armendares-Sagrera ◽  
I. Ruíz de Chávez ◽  
H. Marquez-Monter ◽  
R. Aznar
Keyword(s):  
Surface Epithelium ◽  
Secretory Cells ◽  
Turner's Syndrome ◽  
Ciliated Cells ◽  
Turner’S Syndrome ◽  
Exogenous Hormone ◽  
Ovarian Dysgenesis ◽  
Transmission Electron ◽  
Normal Women ◽  
Microscopy Examination

It is a well documented fact that endometrial hyperplasia and adenocarcinoma may develop in women with Turner's syndrome who had received unopposed estrogen treatment (1), as well as in normal women under contraceptive medication with the sequential regime (2). The purpose of the present study was to characterize the possible changes in surface and glandular epithelium in these women who were treated with a sequential regime for a period of between three and eight years. The aim was to find organelle modifications which may lead to the understanding of the biology of an endometrium under exogenous hormone stimulation. Light microscopy examination of endometrial biopsies of nine patients disclosed a proliferative pattern; in two of these, there was focal hyperplasia. With the scanning electron microscope the surface epithelium in all biopsies showed secretory cells with microvilli alternating with non secretory ciliated cells. Regardless of the day of the cycle all biopsies disclosed a large number of secretory cells rich in microvilli (fig.l) with long and slender projections some of which were branching (fig. 2).

Ultrastructural studies of the relationship between actin filaments and secretory granules

1990 ◽  
Vol 48 (3) ◽  
pp. 458-459
Author(s):  
Ellen Holm Nielsen
Keyword(s):  
Electron Microscopy ◽  
Colloidal Gold ◽  
Actin Filaments ◽  
Secretory Granules ◽  
Secretory Cells ◽  
Ultrastructural Studies ◽  
Transmission Electron ◽  
Granule Membrane ◽  
Ultrathin Sections ◽  
Lowicryl K4m

In secretory cells a dense and complex network of actin filaments is seen in the subplasmalemmal space attached to the cell membrane. During exocytosis this network is undergoing a rearrangement facilitating access of granules to plasma membrane in order that fusion of the membranes can take place. A filamentous network related to secretory granules has been reported, but its structural organization and composition have not been examined, although this network may be important for exocytosis.Samples of peritoneal mast cells were frozen at -70°C and thawed at 4°C in order to rupture the cells in such a gentle way that the granule membrane is still intact. Unruptured and ruptured cells were fixed in 2% paraformaldehyde and 0.075% glutaraldehyde, dehydrated in ethanol. For TEM (transmission electron microscopy) cells were embedded in Lowicryl K4M at -35°C and for SEM (scanning electron microscopy) they were placed on copper blocks, critical point dried and coated. For immunoelectron microscopy ultrathin sections were incubated with monoclonal anti-actin and colloidal gold labelled IgM. Ruptured cells were also placed on cover glasses, prefixed, and incubated with anti-actin and colloidal gold labelled IgM.

scholarly journals Anaphylactic Degranulation of Mast Cells: Focus on Compound Exocytosis

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Ofir Klein ◽  
Ronit Sagi-Eisenberg
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Molecular Mechanisms ◽  
Secretory Granules ◽  
Cell Types ◽  
Secretory Cells ◽  
Regulated Exocytosis ◽  
Open Questions ◽  
Conflicting Evidence ◽  
Compound Exocytosis

Anaphylaxis is a notorious type 2 immune response which may result in a systemic response and lead to death. A precondition for the unfolding of the anaphylactic shock is the secretion of inflammatory mediators from mast cells in response to an allergen, mostly through activation of the cells via the IgE-dependent pathway. While mast cells are specialized secretory cells that can secrete through a variety of exocytic modes, the most predominant mode exerted by the mast cell during anaphylaxis is compound exocytosis—a specialized form of regulated exocytosis where secretory granules fuse to one another. Here, we review the modes of regulated exocytosis in the mast cell and focus on compound exocytosis. We review historical landmarks in the research of compound exocytosis in mast cells and the methods available for investigating compound exocytosis. We also review the molecular mechanisms reported to underlie compound exocytosis in mast cells and expand further with reviewing key findings from other cell types. Finally, we discuss the possible reasons for the mast cell to utilize compound exocytosis during anaphylaxis, the conflicting evidence in different mast cell models, and the open questions in the field which remain to be answered.

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