Fine structure of the vitteline cells in the cestode Proteocephalus longicollis (proteocephalidea)

1978 ◽  
Vol 36 (2) ◽  
pp. 442-443
Author(s):  
Z. Swiderski ◽  
R. D. Eklu-natey ◽  
L. Subilia ◽  
H. Huggel
Keyword(s):  
Endoplasmic Reticulum ◽  
Lipid Droplets ◽  
Secretory Activity ◽  
Granular Endoplasmic Reticulum ◽  
Secretory Cells ◽  
Cytoplasmic Matrix ◽  
Shell Protein ◽  
Vitelline Cells ◽  
Shell Globule ◽  
Spherical Nuclei

The mature vitelline cells of Proteocephalus longicollis (Zeder, 1800) are ovoid or spherical and measure about 30μm in diameter. They represent the holocrine type of secretory cells.The spherical nuclei, about 10μm in diameter, are localized in the central part of the cell. They contain more or less prominent nucleoli enclosed in the moderately electrondense nucleoplasm (Fig. 1).The cytoplasm (Fig. 2, 3, 4) is packed with numerous shell globules of heterogenous type, large lipid droplets, and a few glycogen islands composed mainly of α-glycogen rosettes.The remaining granular cytoplasmic matrix (Fig. 3, 4) contains: (a) numerous polysomes, (b) cysternae of granular endoplasmic reticulum, (c) several mitochondria, and (d) extended Golgi regions, composed of vesicles of different sizes and density.The extensive development of granular endoplasmic reticulum (GER) and Golgi complexes indicates high secretory activity of these cells. Both Golgi and GER are evidently engaged in shell globule formation and are considered therefore to function as the shell-protein producing units

scholarly journals Special features of ultrastructural organization steroid-secretory cells in the gonads of juveniles of cyclostomes and fishes

2019 ◽  
Vol 323 (4) ◽  
pp. 442-450
Author(s):  
M.V. Mosyagina ◽  
O.V. Zelennikov
Keyword(s):  
Endoplasmic Reticulum ◽  
Pink Salmon ◽  
Secretory Activity ◽  
Volume Density ◽  
Oncorhynchus Gorbuscha ◽  
Simultaneous Increase ◽  
Secretory Cells ◽  
Ultrastructural Organization ◽  
Activity Increase ◽  
Lipid Inclusions

The comparative ultrastructural analysis of steroid-secretory cells (SC) in gonads of youngs lamprey Lampetra fluviatilis (Linnaeus 1758), Siberian sturgeon Acipenser baerii Brandt 1869, sterlet A. ruthenus Linnaeus, 1758, rainbow trout Oncorhynchus mykiss (Walbaum 1792) and pink salmon Oncorhynchus gorbuscha (Walbaum 1792) at similar stages of gametogenesis was carried out. The SC localization and size, the diameters of mitochondria, tubules of agranular reticulum, lipid inclusions and also the relative volume density of these structures were determined and calculated. It is concluded that localization of SC in gonads and their activity changes are closely related to the processes of sex differentiation and the growth of oocytes. Thus, in females of all studied species there was a change in SC localization in the direction of stroma→theca→granulosa of previtellogenic oocytes with a simultaneous increase of their secretory activity (increase in SC size, size and volume density of mitochondria and of agranular endoplasmic reticulum tubules). In males, during gametogenesis, the SC localization also changed in the direction of epithelium→stroma testicular with an increase of their secretory activity. In this case, the largest and most active SC were found in the stroma of pink salmon testicular during the natural sex inversion. At the same time, however, were revealed differences in SC ultrastructural organization, appeared to be of species-specific nature. The highest average diameter of the agranular endoplasmic reticulum tubules was observed in sturgeon SC and they are characterized by a large number of lipid inclusions in early stages of gametogenesis. This should be taken into account when comparatively analysing of quantitative data in fish of different systematic groups.

Development of the vitellaria of the liver fluke, Fasciola hepatica in the rat host

Parasitology ◽  
2001 ◽  
Vol 123 (5) ◽  
pp. 509-518 ◽  
Author(s):  
M. W. ROBINSON ◽  
L. M. COLHOUN ◽  
I. FAIRWEATHER ◽  
G. P. BRENNAN ◽  
J. H. WAITE
Keyword(s):  
Fasciola Hepatica ◽  
Liver Parenchyma ◽  
The Body ◽  
Adult Fluke ◽  
Shell Protein ◽  
Body Development ◽  
Transmission Electron ◽  
Electron Immunocytochemistry ◽  
Vitelline Cells ◽  
Shell Globule

The development of the vitellaria of Fasciola hepatica within the liver of its rat host was studied by means of whole-mount stained preparations and transmission electron microscopy, together with light and electron immunocytochemistry using an antibody to vitelline protein B, an eggshell precursor protein synthesized by F. hepatica. No vitelline cells could be identified in flukes recovered from the liver parenchyma, by any of the methods used. In contrast, follicles were present in flukes at the earliest time of recovery from the bile duct, namely, 5 weeks 3 days post-infection. The vitellaria in these flukes formed a row of small follicles on either side of the body. Development of the follicles was rapid: by 6 weeks 3 days, the vitellaria resembled those in the adult fluke and eggs were present in the uterus. Immunolabelling was confined to the shell protein globules in the vitelline cells, confirming the packaging of the eggshell protein within the shell globule clusters.

scholarly journals LIVER PARENCHYMAL CELL INJURY

1963 ◽  
Vol 19 (1) ◽  
pp. 139-157 ◽  
Author(s):  
Edward S. Reynolds
Keyword(s):  
Endoplasmic Reticulum ◽  
Plasma Membrane ◽  
Carbon Tetrachloride ◽  
Cell Injury ◽  
Chemical Interaction ◽  
Parenchymal Cell ◽  
Granular Endoplasmic Reticulum ◽  
Liver Parenchymal Cell ◽  
Cytoplasmic Matrix ◽  
Liver Parenchymal

The structure of the endoplasmic reticulum, plasma membrane, mitochondria, and Golgi apparatus of the liver parenchymal cell is strikingly altered within 1 hour following the administration of a single oral dose of carbon tetrachloride to rats. Progressive loss of glucose-6-phosphatase activity accompanies dispersal of the ergastoplasm. Electron microscopy reveals that these changes are associated with vacuolization of the cisternae of the granular endoplasmic reticulum, degranulation of its membranes, and the appearance of increased number of free ribosomes in the adjacent cytoplasmic matrix. Concomitantly, calcium enters the liver parenchymal cell and is sequestered by mitochondria. First increased at 30 minutes, calcium content is maximal at 1 hour and returns to normal at 2 hours. Although succinic and glutamic dehydrogenase activity patterns within the liver lobule are unaffected, liver cell mitochondria enlarge and some appear to fuse or assume cup-like configurations. Microvilli lining the space of Disse become irregularly indistinct and increasingly pleomorphic by 30 minutes when the plasma membrane becomes increasingly permeable to calcium. Golgi vesicles swell and discharge their granules during the period of poisoning studied. Although all the changes observed may be the result of direct interaction of carbon tetrachloride with the membranes of the cytoplasmic constituents of the liver parenchymal cell, the possibility that the irreversible changes observed in the granular endoplasmic reticulum may be due to the chemical interaction between the poison and this system is discussed.

scholarly journals THE RESPONSE OF VENTRAL HORN NEURONS TO AXONAL TRANSECTION

1972 ◽  
Vol 53 (1) ◽  
pp. 24-37 ◽  
Author(s):  
Donald L. Price ◽  
Keith R. Porter
Keyword(s):  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Morphological Changes ◽  
Ventral Horn ◽  
Granular Endoplasmic Reticulum ◽  
Neuronal Nucleus ◽  
Axoplasmic Flow ◽  
Cytoplasmic Matrix ◽  
Show Evidence ◽  
Axonal Transection

The morphological changes induced in the frog ventral horn neurons by axonal transection have been studied with the electron microscope. During the first 2 wk after axotomy the neuronal nucleus becomes more translucent and the nucleolus becomes enlarged and less compact. The cisternae of the granular endoplasmic reticulum vesiculate and ribosomes dissociate from membranes. Free ribosomes and polysomes are dispersed in the cytoplasmic matrix. Neurofilaments and neurotubules are increased in number. These structures appear to be important in the regeneration of the axon. It is proposed that neurotubules, neurofilaments, and axoplasmic matrix are synthesized by the free polyribosomes in the chromatolytic neuron. By the fourth postoperative week, the neurons show evidence of recovery. The cytoplasm is filled with profiles of granular endoplasmic reticulum and many intercisternal polysomes. The substances being manufactured by the newly formed granular endoplasmic reticulum are not clearly defined, but probably include elements essential to electrical and chemical conduction of impulses. The significance of these observations in respect to recent studies of axoplasmic flow is discussed.

Ultrastructure of vitellocytes in the cestode Progrillotia pastinacae Dollfus, 1946 (Trypanorhyncha, Progrillotiidae)

2006 ◽  
Vol 51 (3) ◽  
Author(s):  
Zdzisław Świderski ◽  
Jordi Miquel ◽  
Daniel Młocicki ◽  
Lassad Neifar ◽  
Barbara Grytner-Zięcina ◽  
...  
Keyword(s):  
Lipid Droplets ◽  
Saturated Fatty Acids ◽  
Cell Organelles ◽  
Numerous Cell ◽  
Perinuclear Cytoplasm ◽  
Vitelline Cells ◽  
Shell Globule ◽  
Characteristic Features ◽  
Trypanorhynch Cestode ◽  
Mature Vitellocytes

AbstractThe present study describes the ultrastructure of mature vitellocytes of the trypanorhynch cestode Progrillotia pastinacae Dollfus, 1946 (Progrillotiidae), a parasite of the common stingray Dasyatis pastinaca (Linnaeus, 1758) (Dasyatidae). The vitelline cells of this species measure about 24 μm in length and about 20 μm in width. They have small, elongated, slightly lobulated nuclei, about 4–5 μm in length, with large dense elongated nucleoli and numerous irregularly-shaped dense clumps of heterochromatin. The extensive cytoplasm is rich in numerous cell organelles and cell inclusions. While the perinuclear cytoplasm contains numerous long parallel cisternae of GER, ribo-and polyribosomes, several Golgi complexes and mitochondria, the peripheral cytoplasm contains predominantly three types of cell inclusions: a great number of large lipid droplets, several shell globule clusters, and a very small amount of glycogen-like particles. The most characteristic features of vitellocytes in P. pastinacae are having almost no traces of glycogen and the great number of large, highly osmiophobic lipid droplets representing saturated fatty acids. The presence of large amounts of lipids also in two other trypanorhynchs, Grillotia erinaceus (Beneden, 1858) Guiart, 1927 and Dollfusiella spinulifera (Beveridge et Jones, 2000) Beveridge, Neifar et Euzet, 2004, is in strong contrast to the condition in the most evolved cestodes, Cyclophyllidea, that usually show no trace of lipids.

Ultrastructure of Luteal Cells in Fully Formed and Regressing Corpora Lutea During Pregnancy and Lactation in the Marsupials Isoodon Macrourus and Perameles Nasuta.

1980 ◽  
Vol 28 (2) ◽  
pp. 195 ◽  
Author(s):  
DE Hollis ◽  
AG Lyne
Keyword(s):  
Endoplasmic Reticulum ◽  
Lipid Droplets ◽  
Smooth Endoplasmic Reticulum ◽  
Cell Junction ◽  
Corpora Lutea ◽  
Cholesterol Crystals ◽  
Luteal Cells ◽  
Pregnancy And Lactation ◽  
Advanced Stages ◽  
Spherical Nuclei

Corpora lutea (CL) collected from 23 bandicoots (I. macrourus and P. nasuta), from day 5 of pregnancy (gestation 12.5 days) to day 53 of lactation (lactation c. 60 days), were examined with the electron microscope. The luteal cells of fully formed CL (from day 5 of pregnancy to day 44 of lactation) were large and contained spherical nuclei with distinct nucleoli. The amount of heterochromatin increased during the latter part of this period. The cytoplasm contained numerous lipid droplets and abundant smooth endoplasmic reticulum (SER). Granular endoplasmic reticulum (GER) was less common. Mitochondria were most numerous from day 16 to day 44 of lactation and some of them contained large osmiophilic inclusions. Several types of granules and inclusions were present in the cytoplasm. During pregnancy, small dense-cored granules were common in P. nasuta and sparse in I. macrourus. They were still present in small numbers during early lactation in P. nasuta but were absent throughout lactation in I. macrourus. A special type of cell junction associated with endoplasmic reticulum was present between the luteal cells in P. nasuta but not in I. macrourus. The luteal cells of regressing CL on days 48, 50 and 53 of lactation were markedly reduced in size, with small irregularly shaped nuclei containing clumps of heterochromatin and indistinct nucleoli. The cells still contained numerous lipid droplets, and osmiophilic inclusions were still present in some of the mitochondria, which were reduced in number (and absent in the animal at day 50). Lancet-shaped spaces, which probably initially contained cholesterol crystals extracted by solvents during processing, were present in some of the regressing luteal cells. Organelles, including SER and GER, were either sparse or unrecognizable in luteal cells at advanced stages of regression. In general, the ultrastructural features of the luteal cells in fully formed and regressing CL of bandicoots were similar to those described in active and regressing CL of eutherian mammals.

Electron microscopical study to assess thein vitroeffects of the synthetic trioxolane OZ78 against the liver fluke,Fasciola hepatica

Parasitology ◽  
2009 ◽  
Vol 136 (11) ◽  
pp. 1325-1337 ◽  
Author(s):  
L. HALFERTY ◽  
J. F. O'NEILL ◽  
G. P. BRENNAN ◽  
J. KEISER ◽  
I. FAIRWEATHER
Keyword(s):  
Endoplasmic Reticulum ◽  
Lipid Droplets ◽  
Fasciola Hepatica ◽  
Microscopical Study ◽  
Granular Endoplasmic Reticulum ◽  
Autophagic Vacuoles ◽  
Transmission Electron ◽  
Electron Microscopical ◽  
Tegumental Syncytium

SUMMARYAdultFasciola hepaticawere incubated for 48 hin vitroin the synthetic peroxide, OZ78 at a concentration of 100 μg/ml and then prepared for scanning and transmission electron microscopy. There was limited disruption to the external fluke surface, with only slight swelling and blebbing of the interspinal tegument in the midbody and ventral tail regions. By contrast, significant disruption was observed to the ultrastructure of the tegument and subtegumental tissues. There was severe swelling of the basal infolds in the tegumental syncytium and the flooding spread internally to affect the subtegumental tissues. In the tegumental system, there was swelling of the cisternae of granular endoplasmic reticulum and of the mitochondria, with the latter showing signs of breaking down. Autophagic vacuoles and lipid droplets were present and the synthesis of tegumental secretory bodies was much reduced. The gastrodermal cells were severely affected, with swelling and degeneration of the mitochondria and the presence of autophagic vacuoles and lipid droplets. The granular endoplasmic reticulum was swollen and vesiculated and the cells contained few secretory bodies. Both the vitelline and testis follicles showed evidence of extensive cellular disruption and degeneration. This study confirms previous data indicating the potential flukicidal activity of OZ78.

scholarly journals The Fine Structure of the Epithelial Cells of the Mouse Prostate

1960 ◽  
Vol 7 (3) ◽  
pp. 511-513 ◽  
Author(s):  
David Brandes ◽  
Adolfo Portela
Keyword(s):  
Endoplasmic Reticulum ◽  
Smooth Muscle ◽  
Fine Structure ◽  
Epithelial Cells ◽  
Connective Tissue ◽  
Cell Membrane ◽  
Secretory Cells ◽  
Ventral Lobe ◽  
Cytoplasmic Matrix ◽  
Mouse Prostate

The fine structure of the epithelial cells of one component of the prostatic complex of the mouse—the ventral lobe—has been investigated by electron microscopy. This organ is composed of small tubules, lined by tall simple cuboidal epithelium, surrounded by smooth muscle and connective tissue. Electron micrographs of the epithelial cells of the ventral lobe show these to be limited by a cell membrane, which appears as a continuous dense line. The nucleus occupies the basal portion of the cell and the nuclear envelope consists of two membranes. The cytoplasmic matrix is of moderately low density. The endoplasmic reticulum consists of elongated, circular, and oval profiles representing the cavities of this system bounded by rough surfaced membranes. The Golgi apparatus appears localized in a region between the apical border and the nucleus, and is composed of the usual elements found in secretory cells (3, 9). At the base of the cells, a basement membrane is visible in close contact with the outer aspect of the cell membrane. A space of varying width, which seems to be occupied by connective tissue, separates the epithelial cells from the surrounding smooth muscle fibers and the blood vessels. Bodies with the appearance of portions of the cytoplasm, mitochondria, or profiles of the endoplasmic reticulum can be seen in the lumina of the acini and on the bases of these pictures and others of the apical region the mechanism of secretion by these cells is discussed. The fine structural organization of these cells is compared with that of another component of the mouse prostate—the coagulating gland.

A Study of Granule Formation in the Bat Parafollicular Cell

1969 ◽  
Vol 5 (2) ◽  
pp. 531-559
Author(s):  
E. A. NUNEZ ◽  
R. P. GOULD ◽  
S. J. HOLT
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Complex ◽  
Secretory Granules ◽  
Granular Endoplasmic Reticulum ◽  
Secretory Product ◽  
Central Mass ◽  
Granule Formation ◽  
Cytoplasmic Matrix ◽  
Parafollicular Cell ◽  
Parafollicular Cells

The fine structure of the bat thyroid parafollicular cell has been examined at monthly intervals throughout the hibernating period. During November and December parafollicular cells appear either partly or totally degranulated and intact dense secretory granules are relatively sparse. The degranulated cells exhibit an inconspicuous Golgi complex and relatively few lysosome-type bodies. Few degranulated parafollicular cells are present in thyroid glands from bats collected in January. When found they are characterized by the presence of whorls of cytoplasmic agranular membranes which enclose a central mass of cellular debris. January bat thyroids are characterized by the presence of three different types of parafollicular cell. One type contains no secretory granules. The cytoplasmic matrix of this type is rich in granular endoplasmic reticulum and free ribosomes and its small Golgi complex consists of several slightly dilated saccules. In close proximity to the Golgi complex are numerous small to medium-sized vesicles which often appear to merge with Golgi elements. Such vesicles are considered to represent the vehicle by which secretory product is transferred from the endoplasmic reticulum to the Golgi complex. The second type of parafollicular cell differs from the first in containing large numbers of intact dense secretory granules. It is also characterized by an extensive Golgi complex which appears to be forming new secretory granules, and by a less extensive granular endoplasmic reticulum. The third type of parafollicular cell shows a structure intermediate between the first two. The cytoplasm of all three types of January parafollicular cells contains many structures belonging to the lysosomal-vacuolar system, including autophagic vacuoles, vacuolated dense bodies and multivesicular bodies. By February and March only parafollicular cells of type 2 are observed. They contain few lysosome-like structures. It is concluded that during mid-hibernation (January), parafollicular cells undergo a series of intracellular changes during which new dense secretory granules are produced. Accompanying granule formation is an augmentation of lysosome-like structures which probably serve as a means of digesting debris from previous secretory cycles.

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).

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