scholarly journals ELECTRON MICROSCOPY OF THE BURSA OF FABRICIUS OF THE EMBRYONIC CHICK WITH PARTICULAR REFERENCE TO THE LYMPHO-EPITHELIAL NODULES

1962 ◽  
Vol 13 (1) ◽  
pp. 127-146 ◽  
Author(s):  
G. Adolph Ackerman
Keyword(s):  
Endoplasmic Reticulum ◽  
Epithelial Cells ◽  
Embryonic Development ◽  
Golgi Complex ◽  
Bursa Of Fabricius ◽  
Cortical Region ◽  
Electron Microscopic ◽  
Submicroscopic Structure ◽  
Microscopic Studies ◽  
Pass Through

Electron microscopic studies of the bursa of Fabricius during the 15th and 16th day of embryonic development in the chick have shown the following findings in the submicroscopic structure of the cellular elements of the lympho-epithelial follicles. In the medulla, basal endodermal epithelial cells undergo mitosis and differentiation into lymphoblasts. During this transformation, there is a reduction in the amount of rough endoplasmic reticulum, an increase in the number or ribosomes, and frequently an enlargement of the Golgi complex. As lymphoblasts differentiate into medium lymphocytes there is a loss of endoplasmic reticulum, a reduction in the number of ribosomes and in the size of the Golgi complex, as well as a decrease in the number and size of mitochondria and in the size of the cell and nucleus. Cytoplasmic processes of reticular-epithelial cells extend between proliferating lymphocytic cells. Desmosomes connect stellate reticular-epithelial and basal epithelial cells but are not present in lymphocytic cells. Nuclear blebbing and vesiculation are frequently observed in the various cell forms of the developing lympho-epithelial nodules. Although lymphocytes and lymphocytopoietic activities in the cortex are sparse during this stage of embryonic development of the bursa, transitional forms between mesenchymal cells and lymphoblasts have been encountered. In addition, lymphoblasts and/or undifferentiated epithelial cells occasionally may pass through the basement membrane from the medulla into the cortical region of the developing nodule. That lymphocytes in the bursa of Fabricius originate from both endodermal and mesodermal derivatives during embryonic development appears to be consistent with both light and electron microscopic observations.

Hepatic Ultrastructure Changes Induced by Lithocholic Acid

1967 ◽  
Vol 25 ◽  
pp. 162-163 ◽  
Author(s):  
F. G. Zaki
Keyword(s):  
Endoplasmic Reticulum ◽  
Lithocholic Acid ◽  
Smooth Endoplasmic Reticulum ◽  
Protein Diet ◽  
Low Protein Diet ◽  
Electron Microscopic ◽  
Hydropic Degeneration ◽  
Hepatic Cells ◽  
Low Protein ◽  
Microscopic Studies

Addition of lithocholic acid (LCA), a naturally occurring bile acid in mammals, to a low protein diet fed to rats induced marked inflammatory reaction in the hepatic cells followed by hydropic degeneration and ductular cell proliferation. These changes were accompanied by dilatation and hyperplasia of the common bile duct and formation of “gallstones”. All these changes were reversible when LCA was withdrawn from the low protein diet except for the hardened gallstones which persisted.Electron microscopic studies revealed marked alterations in the hepatic cells. Early changes included disorganization, fragmentation of the rough endoplasmic reticulum and detachment of its ribosomes. Free ribosomes, either singly or arranged in small clusters were frequently seen in most of the hepatic cells. Vesiculation of the smooth endoplasmic reticulum was often encountered as early as one week after the administration of LCA (Fig. 1).

Spermatogenesis in the Dragonfly with Particular Reference to the Cytoplasmic Organelles

1972 ◽  
Vol 30 ◽  
pp. 110-111
Author(s):  
Sant S. Sekhon
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Mature Sperm ◽  
Electron Microscopic ◽  
Cytoplasmic Organelles ◽  
Microscopic Studies ◽  
Insect Sperm ◽  
Large Round

Although there have been numerous studies concerning the morphogenetic changes accompanying the maturation of insect sperm, only a few deal with the sperm differentiation in the dragonflies. In two recent electron microscopic studies Kessel, has comprehensively treated the erlationship of microtubules to the nucleus and mid-piece structures during spermiogenesis in the dragonfly. The purpose of this study is to follow the sequential nuclear and cytoplasmic changes which accompany the differentiation of spermatogonium into a mature sperm during spermatogenesis in the dragonfly (Aeschna sp.).The dragonfly spermatogonia are characterized by large round nuclei. Loosely organized chromatin is usually unevenly distributed within the spermatogonial nuclei. The scant cytoplasm surrounding the nucleus contains mitochondria, the Golgi apparatus, elements of endoplasmic reticulum and numerous ribosomes (Fig. 1).

Mise en évidence du rôle, dans la régénération des Amphibiens, d'une glycoprotéine sécrétée par la cape apicale: étude cytochimique et autoradiographique en microscopie électronique

Development ◽  
1974 ◽  
Vol 32 (1) ◽  
pp. 133-145
Author(s):  
Par Claude Chapron
Keyword(s):  
High Resolution ◽  
Epithelial Cells ◽  
Limb Regeneration ◽  
Target Cells ◽  
Silver Particles ◽  
Electron Microscopic ◽  
Microscopic Studies ◽  
High Resolution Autoradiography

Evidence for the role of an apical cap glycoprotein in amphibian regeneration: cytochemical and autoradiographic electron-microscopic studies Early during limb regeneration in the newt, an ectodermal apical cap covering a mesodermal blastema is formed. High-resolution autoradiography of these tissues has been carried out after incorporation of [3H]fucose, which is a precursor of glycoproteins. Autoradiography shows that silver particles are located at first on epithelial cells, then on mesenchymatous cells. This observation is consistent with a hypothesis in which the apical cap would elaborate a glycoprotein acting on the blastema. Substructural autoradiography and cytochemistry also show the importance of cellular surfaces for both cells producing glycoprotein and those which are target cells.

scholarly journals Demonstration of lysosomal and extralysosomal sites for acid phosphatase in mouse kidney tubule cells with p-nitrophenylphosphate lead-salt technique.

1975 ◽  
Vol 23 (6) ◽  
pp. 439-451 ◽  
Author(s):  
H Miyayama ◽  
R Solomon ◽  
M Sasaki ◽  
C W Lin ◽  
W H Fishman
Keyword(s):  
Endoplasmic Reticulum ◽  
Enzyme Activity ◽  
Acid Phosphatase ◽  
Epithelial Cells ◽  
Normal Mouse ◽  
Plasma Membranes ◽  
Mouse Kidney ◽  
Lead Salt ◽  
Acetate Buffer ◽  
Electron Microscopic

Dual localization of acid phosphatase in lysosomal and extralysosomal sites of the tubule epithelial cells of normal mouse kidney was observed at the light and electron microscope level using a modified Gomori lead-salt method with p-nitrophenylphosphate (pNPP) as substrate. Based on previous biochemical and cytochemical findings, we developed optimal conditions for the enzyme activity in extralysosomal sites. The conditions used for the light microscopic level consisted of 1.5 mM PNPP, 2.0 MM Pb(NO3)2 and 0.05 M acetate buffer (pH 5.8). Those for the electron microscopic study required 3.0 mM PNPP, 3.6 MM Pb(NO3)2 and 0.1 M acetate buffer (pH 5.8). This modified lead-salt technique was highly specific and provided a suitable method for the demonstration of nonlysosomal as well as lysosomal sites of acid phosphatase activity in the tubule epithelial cells of normal mouse kidney. As expected, the enzyme activity appeared in the lysosomes, but the prominent reaction in the brush border, the rough endoplasmic reticulum and basal infolding plasma membranes was not anticipated. We were able to demonstrate in situ organelle precursors of microsomal acid phosphatase such as endoplasmic reticulum, plasma membrane and basal infolding membranes showing the same substrate preference, which had been observed previously in biochemical studies in our laboratory. Since the possible participation of alkaline phosphatases, K+-pNPPase or Na+-K+-adenosine triphosphatase was ruled out by use of appropriate inhibitors, the enzyme-reactive sites can be interpreted as reflecting nonspecific acid phosphatase.

Alveolate Reticulum - An Alteration of Endoplasmic Reticulum Observed in Human Tissues

1970 ◽  
Vol 28 ◽  
pp. 88-89
Author(s):  
Betty G. Uzman ◽  
Marjorie Kasac
Keyword(s):  
Endoplasmic Reticulum ◽  
Lymph Node ◽  
Single Cell ◽  
Secretory Cell ◽  
Leukemic Cells ◽  
Human Tissues ◽  
Malignant Histiocytosis ◽  
Electron Microscopic ◽  
Phase Microscopy ◽  
Microscopic Studies

Electron microscopic studies of human tumors have been correlated by phase microscopy of ∼1μ sections with conventional histopathology. In tumor nodules from patients with fibrosarcoma (Fig. 1), malignant histiocytosis, and Hodgkin's disease (Figs. 2, 3, 4); in leukemic cells infiltrating spleen and lymph node; and in one parotid secretory cell (case of acute myeloblastic leukemia) alterations of the granular endoplasmic reticulum have been observed. These structures (indicated by arrows) resemble moth-eaten membranous bodies continuous with the encircling (Figs. 1, 2) or contiguous (Figs. 3, 4) cisternal wall. As many as five such alveolate reticular regions have been observed in a single cell.

An Electron Microscopic Study of the Human Gastric Epithelia with Special Reference to the Cardinal Morphological Changes of the Chief Cells Induced by Insulin Stimulus

1972 ◽  
Vol 30 ◽  
pp. 344-345
Author(s):  
Hiroshi Saito ◽  
Goro Asano ◽  
Kaoru Aihara ◽  
Katsunari Fukushi ◽  
Minoru Yoshida ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Morphological Changes ◽  
Regular Insulin ◽  
Endoscopic Biopsy ◽  
Granular Endoplasmic Reticulum ◽  
Ultrastructural Changes ◽  
Electron Microscopic ◽  
Chief Cells ◽  
Microscopic Studies ◽  
The One

This short communication is dealt with the ultrastructural changes of the chief cells in insulin stimulus in chronic gastritic condition. The bio gastro-endoscopic biopsy was obtained and pepsin activity of the gastric juice was measured in respective cases. Regular insulin of 0.15U/kg was administrated intra-muscularly and in pre-administration of insulin, 10 minutes, 20 minutes and 30 minutes after administration, biopsied specimens were subjected for electron microscopic studies.In the pre-treated chief cells, extensive development of the cysternal structures of the granular endoplasmic reticulum in basal aspect of the cytoplasm and spherical or oval shaped, light homogeneous zymogen granules in supranuclear region and especially apical aspect of the cytoplasm were featured. Moreover, other type of the chief cells as the one characterized by their fragmented and saccular dilated granular endoplasmic reticulum in basal aspect of the cytoplasm, also exist.

Potassium depletion inhibits the intracellular transport of secretory proteins between the endoplasmic reticulum and the Golgi complex

1989 ◽  
Vol 92 (2) ◽  
pp. 173-185
Author(s):  
J.D. Judah ◽  
K.E. Howell ◽  
J.A. Taylor ◽  
P.S. Quinn
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Complex ◽  
Intracellular Transport ◽  
Secretory Pathway ◽  
Subcellular Fractionation ◽  
Secretory Proteins ◽  
Mature Form ◽  
Processing Enzymes ◽  
Microscopic Studies ◽  
K Depletion

In this paper we show that hepatocytes that have been depleted of K+ secrete albumin, alpha-1-anti-trypsin and transferrin at a slower rate than cells to which K+ has been returned. K+ depletion has no effect on the intracellular nucleotide pools, and we provide evidence that the inhibitions of secretion caused by depletion of K+ and depletion of ATP are independent. Studies of the processing of alpha-1-anti-trypsin show that K+ depletion inhibits the formation of the mature form of the protein, but that immature forms are never secreted. In cells to which K+ was returned, secretion of the mature form was restored. This implies that transport is blocked at a point before the proteins reach the processing enzymes. Proteins delayed by K+ depletion are not removed from the secretory pathway, but are free to mix with protein synthesized subsequently. These data are supported by subcellular fractionation experiments, which show that the secretory proteins are delayed before reaching the Golgi complex, and by immunoelectron microscopic studies. These show that in K+-deficient cells the morphology of both the endoplasmic reticulum and the Golgi complex is normal. The secretory proteins are trapped in smooth vesicles that contain reaction product when incubated for glucose-6-phosphatase, a marker for the endoplasmic reticulum.

scholarly journals The Development of the Cnidoblasts of Hydra

1959 ◽  
Vol 5 (3) ◽  
pp. 441-452 ◽  
Author(s):  
David B. Slautterback ◽  
Don W. Fawcett
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Complex ◽  
Interstitial Cell ◽  
Complex Cell ◽  
Electron Microscopic ◽  
Cytoplasmic Matrix ◽  
Virtual Absence ◽  
Cytological Characteristics ◽  
Mode Of Attachment

The general histological organization of Hydra is reviewed and electron microscopic observations are presented which bear upon the nature of the mesoglea, the mode of attachment of the contractile processes of the musculo-epithelial cells, and the cytomorphosis of the cnidoblasts. Particular attention is devoted to the changes in form and distribution of the cytoplasmic organelles in the course of nematocyst formation. The undifferentiated interstitial cell is characterized by a small Golgi complex, few mitochondria, virtual absence of the endoplasmic reticulum, and a cytoplasmic matrix crowded with fine granules presumed to be ribonucleoprotein. These cytological characteristics persist through the early part of the period of interstitial cell proliferation which leads to formation of clusters of cnidoblasts. With the initiation of nematocyst formation in the cnidoblasts, numerous membrane-bounded vesicles appear in their cytoplasm. These later coalesce to form a typical endoplasmic reticulum with associated ribonucleoprotein granules. During the ensuing period of rapid growth of the nematocyst the reticulum becomes very extensive and highly organized. Finally, when the nematocyst has attained its full size, the reticulum breaks up again into isolated vesicles. The Golgi complex remains closely applied to the apical pole of the nematocyst throughout its development and apparently contributes to its enlargement by segregating formative material in vacuoles whose contents are subsequently incorporated in the nematocyst. The elaboration of this complex cell product appears to require the cooperative participation of the endoplasmic reticulum and the Golgi complex. Their respective roles in the formative process are discussed.

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