scholarly journals AN ELECTRON MICROSCOPE STUDY OF MATURE AND DIFFERENTIATING PANETH CELLS IN THE RAT, ESPECIALLY OF THEIR ENDOPLASMIC RETICULUM AND LYSOSOMES

1964 ◽  
Vol 22 (3) ◽  
pp. 633-652 ◽  
Author(s):  
O. Behnke ◽  
H. Moe
Keyword(s):  
Endoplasmic Reticulum ◽  
Small Intestine ◽  
Electron Microscope ◽  
Golgi Complex ◽  
Electron Microscope Study ◽  
Secretory Granules ◽  
Paneth Cells ◽  
Mature Cell ◽  
Adult Rats ◽  
Perinuclear Space

In an electron microsope study, the morphology of mature Paneth cells from the small intestine of adult rats is compared with that of differentiating Paneth cells from young rats 2 to 4 weeks old. All mature cells exhibit a marked polarity similar to that of other exocrine gland cells and contain a well developed endoplasmic reticulum, an elaborate Golgi complex, and numerous large secretory granules; they also possess an abundance of lysosomes. The most conspicuous occurrence in the process of differentiation is the development of the endoplasmic reticulum. The most immature Paneth cells possess an endoplasmic reticulum of the vesicular type, which, during maturation, is replaced by the characteristic lamellated ergastoplasm of the mature cell. At a certain stage of differentiation the cavities of the developing cisternae show numerous communications with the perinuclear space, suggesting an outgrowth of the ergastoplasm from the nuclear envelope. Furthermore, the cavities and the perinuclear space at this particular stage contain a material which shows a remarkable intrinsic periodicity. An identical periodicity was exhibited by material contained in Golgi cisternae and secretory granules. Lysosomes are also present in the differentiating cells.

Ultrastructural comparison of prolactin adenomas of pituitary in men and women

1988 ◽  
Vol 46 ◽  
pp. 346-347
Author(s):  
R.C. Caughey ◽  
U.P. Kalyan-Raman
Keyword(s):  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Phosphate Buffer ◽  
Pituitary Adenomas ◽  
Osmium Tetroxide ◽  
Secretory Granules ◽  
Uranyl Acetate ◽  
En Bloc ◽  
Men And Women ◽  
Transmission Electron

Prolactin producing pituitary adenomas are ultrastructurally characterized by secretory granules varying in size (150-300nm), abundance of endoplasmic reticulum, and misplaced exocytosis. They are also subclassified as sparsely or densely granulated according to the amount of granules present. The hormone levels in men and women vary, being higher in men; so also the symptoms vary between both sexes. In order to understand this variation, we studied 21 prolactin producing pituitary adenomas by transmission electron microscope. This was out of a total of 80 pituitary adenomas. There were 6 men and 15 women in this group of 21 prolactinomas.All of the pituitary adenomas were fixed in 2.5% glutaraldehyde, rinsed in Millonig's phosphate buffer, and post fixed with 1% osmium tetroxide. They were then en bloc stained with 0.5% uranyl acetate, rinsed with Walpole's non-phosphate buffer, dehydrated with graded series of ethanols and embedded with Epon 812 epoxy resin.

scholarly journals Endoplasmic reticulum-to-Golgi transitions upon herpes virus infection

F1000Research ◽  
2018 ◽  
Vol 6 ◽  
pp. 1804 ◽  
Author(s):  
Peter Wild ◽  
Andres Kaech ◽  
Elisabeth M. Schraner ◽  
Ladina Walser ◽  
Mathias Ackermann
Keyword(s):  
Endoplasmic Reticulum ◽  
Nuclear Envelope ◽  
Golgi Complex ◽  
Nuclear Membrane ◽  
Progeny Virus ◽  
Cytoplasmic Matrix ◽  
Outer Nuclear Membrane ◽  
Nuclear Membranes ◽  
Perinuclear Space ◽  
Hsv 1

Background: Herpesvirus capsids are assembled in the nucleus, translocated to the perinuclear space by budding, acquiring tegument and envelope, or released to the cytoplasm via impaired nuclear envelope. One model proposes that envelopment, “de-envelopment” and “re-envelopment” is essential for production of infectious virus. Glycoproteins gB/gH were reported to be essential for de-envelopment, by fusion of the “primary” envelope with the outer nuclear membrane. Yet, a high proportion of enveloped virions generated from genomes with deleted gB/gH were found in the cytoplasm and extracellular space, suggesting the existence of alternative exit routes.Methods: We investigated the relatedness between the nuclear envelope and membranes of the endoplasmic reticulum and Golgi complex, in cells infected with either herpes simplex virus 1 (HSV-1) or a Us3 deletion mutant thereof, or with bovine herpesvirus 1 (BoHV-1) by transmission and scanning electron microscopy, employing freezing technique protocols.Results:  The Golgi complex is a compact entity in a juxtanuclear position covered by a membrane on thecisface. Golgi membranes merge with membranes of the endoplasmic reticulum forming an entity with the perinuclear space. All compartments contained enveloped virions. After treatment with brefeldin A, HSV-1 virions aggregated in the perinuclear space and endoplasmic reticulum, while infectious progeny virus was still produced.Conclusions: The data suggest that virions derived by budding at nuclear membranes are intraluminally transported from the perinuclear space via Golgi -endoplasmic reticulum transitions into Golgi cisternae for packaging. Virions derived by budding at nuclear membranes are infective like Us3 deletion mutants, which  accumulate in the perinuclear space. Therefore, i) de-envelopment followed by re-envelopment is not essential for production of infective progeny virus, ii) the process taking place at the outer nuclear membrane is budding not fusion, and iii) naked capsids gain access to the cytoplasmic matrix via impaired nuclear envelope as reported earlier.

An Electron-Microscope Study of the Cytoplasmic Inclusions in the Neurones of Locusta Migratoria

1962 ◽  
Vol s3-103 (62) ◽  
pp. 147-153
Author(s):  
DOREEN E. ASHHURST ◽  
J. A. CHAPMAN
Keyword(s):  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Microscope Study ◽  
Electron Microscope Study ◽  
Locusta Migratoria ◽  
Cytoplasmic Inclusions ◽  
Double Membrane

The cytoplasmic inclusions of the neurones of adult Locusta migratoria have been examined in the electron microscope. The mitochondria are easily recognized by their cristae and outer double membranes. Electron-dense inclusions, also with an outer double membrane but possessing numerous closely spaced internal lamellae in various orientations, are probably small lipochondria. Larger and more diffuse inclusions comprising crescent-shaped aggregates of loosely packed parallel lamellae and vesicles are present; the possible significance of these larger inclusions is discussed. A system of numerous small vesicles distributed throughout the cytoplasm makes up the endoplasmic reticulum.

scholarly journals Relationship between the golgi apparatus, gerl, and secretory granules in acinar cells of the rat exorbital lacrimal gland

1977 ◽  
Vol 74 (2) ◽  
pp. 399-413 ◽  
Author(s):  
AR Hand ◽  
C Oliver
Keyword(s):  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Golgi Apparatus ◽  
Lacrimal Gland ◽  
Secretory Granules ◽  
Acinar Cells ◽  
Secretory Proteins ◽  
Thiamine Pyrophosphatase ◽  
Variable Distance ◽  
Secretory Enzyme

The method of secretory granuleformation in the acinar cells of the rat exorbital lacrimal gland was studied by electron microscope morphological and cytochemical techniques. Immature secretory granules at the inner face of the Golgi apparatus were frequently attached to a narrow cisternal structure similar to GERL as described in neurons by Novikoff et al. (Novikoff, P. M., A. B. Novikoff, N. Quintana, and J.-J. Hauw. 1971. J. Cell Bio. 50:859-886). In the lacrimal gland. GERL was located adjacent to the inner Golgi saccule, or separated from it by a variable distance. Portions of GERL were often closely paralleled by modified cisternae of rough endoplasmic reticulum (RER), which lacked ribosomes on the surface adjacent to GERL. Diaminobenzidine reaction product of the secretory enzyme peroxidase was localized in the cisternae of the nuclear envelope, RER, peripheral Golgi vesicles, Golgi saccules, and immature and mature secretory granules. GERL was usually free of peroxidase reaction product or contained only a small amount. Thiamine pyrophosphatase reaction product was present in two to four inner Golgi saccules; occasionally, the innermost saccule was dilated and fenestrated, and contained less reaction product than the next adjacent saccule. Acid phosphatase (AcPase) reaction product was present in GERL, immature granules, and, rarely, in the innermost saccule, but not in the rest of the Golgi saccules. Thick sections of AcPase preparations viewed at 100 kV revealed that GERL consisted of cisternal, and fenestrated or tublular portions. The immature granules were attached to GERL by multiple connections to the tublular portions. These results suggest that, in the rat exorbital lacrimal gland, the Golgi saccules participate in the transport of secretory proteins, and that GERL is involved in the formation of secretory granules.

Electron-microscope studies of Fasciola hepatica III. Further observations on the tegument and associated structures

Parasitology ◽  
1967 ◽  
Vol 57 (4) ◽  
pp. 633-637 ◽  
Author(s):  
L. T. Threadgold
Keyword(s):  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Golgi Complex ◽  
Technical Assistance ◽  
Fasciola Hepatica ◽  
Glutaraldehyde Fixation ◽  
Research Associate ◽  
New Findings

Additional ultrastructural features of the tegument of Fasciola hepatica, after glutaraldehyde fixation and high resolution, have been observed.Two distinct types of tegumental cells are shown to be present, the type 1 cell having been previously described. Details of the fine structure of the nucleus, mitochondria, endoplasmic reticulum and Golgi complex of the type 2 cell are given. The type 2 cell is characterized by biconcave secretory bodies derived from the Golgi complex and the latter is intimately related to the granular endoplasmic reticulum, from which it is derived by blebbing. The type 2 cells are connected by protoplasmic tubes to the same surface syncytium as type 1 cells.These new findings of the structure of the tegument of Fasciola are compared with previous reports on the ultrastructure of the tegument in other flukes.I should like to express my sincere thanks to the following: the Wellcome Trust and S.R.C. for grants to purchase an Akashi TRS 50 and an A.E.I. E.M. 6B electron microscope respectively; the Royal Society for a personal grant to purchase a Reichert Ultramicrotome and a vacuum coating unit.My thanks are also due to Mr W. Ferguson for photographic skill and to Mr A. Lyness for technical assistance and microscope maintenance, and my Research Associate, Mrs S. S. E. Dermott, for expert electron-microscopy.

scholarly journals Endoplasmic reticulum-to-Golgi transitions upon herpes virus infection

F1000Research ◽  
2017 ◽  
Vol 6 ◽  
pp. 1804 ◽  
Author(s):  
Peter Wild ◽  
Andres Kaech ◽  
Elisabeth M. Schraner ◽  
Ladina Walser ◽  
Mathias Ackermann
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Nuclear Envelope ◽  
Golgi Complex ◽  
Progeny Virus ◽  
Perinuclear Space ◽  
Exit Route ◽  
Scanning Electron ◽  
Hsv 1

Background: Herpesvirus capsids are assembled in the nucleus before they are translocated to the perinuclear space by budding, acquiring tegument and envelope, or releasing to the cytoplasm in a “naked” state via impaired nuclear envelope. One model proposes that envelopment, “de-envelopment” and “re-envelopment” are essential steps for production of infectious virus. Glycoproteins gB/gH were reported to be essential for de-envelopment, by fusion of the “primary” envelope with the outer nuclear membrane. Yet, a high proportion of enveloped virions generated from genomes with deleted gB/gH were found in the cytoplasm and extracellular space, suggesting the existence of an alternative exit route.Methods: We investigated the relatedness between the nuclear envelope and membranes of the endoplasmic reticulum and Golgi complex, in cells infected with either herpes simplex virus 1 (HSV-1) or a Us3 deletion mutant thereof, or with bovine herpesvirus 1 (BoHV-1) by transmission and scanning electron microscopy, employing freezing technique protocols that lead to improved spatial and temporal resolution.Results: Scanning electron microscopy showed the Golgi complex as a compact entity in a juxtanuclear position covered by a membrane on thecisface. Transmission electron microscopy revealed that Golgi membranes merge with membranes of the endoplasmic reticulum forming an entity with the perinuclear space. All compartments contained enveloped virions. After treatment with brefeldin A, HSV-1 virions aggregated in the perinuclear space and endoplasmic reticulum, while infectious progeny virus was still produced.Conclusions: The data strongly suggest that virions are intraluminally transported from the perinuclear space via Golgi complex-endoplasmic reticulum transitions into Golgi cisternae for packaging into transport vacuoles. Furthermore, virions derived by budding at nuclear membranes are infective as has been shown for HSV-1 Us3 deletion mutants, which almost entirely accumulate in the perinuclear space. Therefore, de-envelopment followed by re-envelopment is not essential for production of infective progeny virus.

Desiccation causes the proliferation of multicellular hairs, but not mucilage papillae, in Cryptothallus mirabilis (Hepatophyta): a correlated light and electron microscope study

1990 ◽  
Vol 68 (3) ◽  
pp. 697-706 ◽  
Author(s):  
Jeffrey G. Duckett ◽  
Karen S. Renzaglia ◽  
Keith Pell
Keyword(s):  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Acid Phosphatase ◽  
Endophytic Fungus ◽  
Electron Microscope Study ◽  
Secretory Phase ◽  
Golgi Bodies ◽  
Dense Cytoplasm ◽  
Thin Walled ◽  
Multicellular Hair

When Cryptothallus dries out over periods of 4–20 days, the dorsal surfaces of the thalli become covered with multicellular hairs. The distribution of mucilage papillae and the endophytic fungus are not affected by desiccation. The hairs are thin walled and highly vacuolated whereas the mucilage papillae, like their secretory counterparts in Marchantia and mosses, are thick walled with dense cytoplasm containing stacks of endoplasmic reticulum and numerous Golgi bodies. Cytochemistry shows that the secretion is rich in carbohydrates and is derived from Golgi vesicles. After an active secretory phase, senescence of the mucilage papillae is associated with acid phosphatase activity. Key words: Aneura, Cryptothallus, desiccation, liverwort, mucilage papilla, multicellular hair, ultrastructure.

scholarly journals AN ELECTRON MICROSCOPE STUDY OF YOLK FORMATION DURING OOGENESIS IN LEBISTES RETICULATUS GUPPYI

1966 ◽  
Vol 28 (2) ◽  
pp. 209-232 ◽  
Author(s):  
Michael J. Droller ◽  
Thomas F. Roth
Keyword(s):  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Microscope Study ◽  
Electron Microscope Study ◽  
Structural Changes ◽  
Extracellular Material ◽  
Yolk Formation ◽  
Selective Uptake ◽  
Lebistes Reticulatus

The present investigation describes the fine structural changes that occur during proteid yolk formation in the developing oocytes of the guppy (Lebistes reticulatus), an ovoviviparous teleost. These changes suggest the operation of a number of different intra- and extraoocyte processes that may account for the synthesis and deposition of the proteid yolk. Early in oogenesis, the egg's Golgi systems proliferate and begin to disclose an electron-opaque content. Numerous 70-mµ diameter vesicles apparently pinch off from the Golgi systems, transport this material through the egg, and probably then fuse to form a crenate, membrane-limited yolk droplet. At the same time, the rough-surfaced endoplasmic reticulum accumulates a flocculent substance that differs in appearance from the Golgi content. Smooth vesicles, presumably derived from the ER, then coalesce to form a second type of intraoocyte yolk droplet. These dissimilar, separately derived droplets subsequently fuse, thus combining the materials that constitute the intraoocyte contribution to the proteid yolk. Somewhat later in development, the egg appears to ingest extracellular material via 75-mµ diameter bristle-coated micropinocytotic pits and vesicles. These structures apparently fuse to form tubules which then coalesce into large yolk droplets. At a later stage, bristle-coated micropinocytotic vesicles of 100 mµ diameter presumably take up a material that is then probably immediately deposited into a second type of proteid yolk droplet. It is postulated that these two different micropinocytotic structures are specifically involved with the selective uptake of dissimilar extracellular proteid materials.

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