scholarly journals Ultrastructural Evaluation of Thyroid Parafollicular Cells of Pigs with Naturally Occurring Atrophic Rhinitis

1970 ◽  
Vol 7 (2) ◽  
pp. 171-185 ◽  
Author(s):  
A.W. Fetter ◽  
C.C. Capen

The thyroid parafollicular cells of 4-month-old control pigs and pigs with naturally occurring atrophic rhinitis were evaluated ultrastructurally. Significant difference was not observed in populations of parafollicular cells between the 2 groups of pigs. Parafollicular cells occurred in actively synthesizing and storage phases of the secretory cycle in both groups. Actively synthesizing cells had a well-developed endoplasmic reticulum, aggregated ribosomes, and prominent Golgi apparatuses with prosecretory granules. The cytoplasm of parafollicular cells in the storage phase was packed with electron-dense secretory granules. The Golgi apparatus and ergastoplasm were less prominent. There was no evidence to suggest that an interference in the synthesis or release of thyrocalcitonin by parafollicular cells was of criologic importance in the pathogenesis of atrophic rhinitis.

1967 ◽  
Vol 4 (4) ◽  
pp. 348-365 ◽  
Author(s):  
C. C. Capen ◽  
S. L. Martin ◽  
A. Koestner

An acidophil adenoma in a 12-year-old spayed boxer dog resulted in clinical signs related to a space-occupying lesion of the hypophysis. There were two types of acidophils, as determined ultrastructurally, within the adenoma. The predominating type was interpreted to be in the storage phase of the secretory cycle as the cytoplasm was densely granulated and the organelles concerned with protein synthesis and packaging of secretory products were poorly developed. The second, less common type contained few secretory granules, had a well developed endoplasmic reticulum and Golgi apparatus, and was interpreted to be secretorily active. The secretory granules of the neoplastic acidophils were large (420 m μ), uniformly electron-dense, and had a narrow submembranous space. An adenoma of the pancreatic islets was also present.


1968 ◽  
Vol 5 (6) ◽  
pp. 481-503
Author(s):  
A. W. Fetter ◽  
C. C. Capen

The secretory activity of the parathyroid glands of 4-month-old pigs with naturally occurring atrophic rhinitis was evaluated ultrastructurally and compared to control pigs of the same age. The principal difference between the 2 groups was a transformation of the predominately inactive chief cell population in control pigs into chief cells of a more active stage of their secretory cycle in diseased pigs. The active chief cells in pigs with atrophic rhinitis had an electron-dense cytoplasm, large Golgi apparatuses, aggregated ribosomes, and abundant endoplasmic reticulum. Secretory granules occurred in increased numbers in the active chief cells of diseased pigs compared to control pigs. The degree of parathyroid stimulation appeared to be mild in pigs with atrophic rhinitis and the stimulative effects seemed to be greater on hormonal synthesis than on hormonal secretion. There was no evidence of severe or prolonged parathyroid stimulation.


1974 ◽  
Vol 60 (1) ◽  
pp. 92-127 ◽  
Author(s):  
Melvyn Weinstock ◽  
C. P. Leblond

The elaboration of dentin collagen precursors by the odontoblasts in the incisor teeth of 30–40-g rats was investigated by electron microscopy, histochemistry, and radioautography after intravenous injection of tritium-labeled proline. At 2 min after injection, when the labeling of blood proline was high, radioactivity was restricted to the rough endoplasmic reticulum, indicating that it is the site of synthesis of the polypeptide precursors of collagen, the pro-alpha chains. At 10 min, when the labeling of blood proline had already declined, radioactivity was observed in spherical portions of Golgi saccules containing entangled threads, and, at 20 min, radioactivity appeared in cylindrical portions containing aggregates of parallel threads. The parallel threads measured 280–350 nm in length and stained with the low pH-phosphotungstic acid technique for carbohydrate and with the silver methenamine technique for aldehydes (as did extracellular collagen fibrils). The passage of label from spherical to cylindrical Golgi portions is associated with the reorganization of entangled into parallel threads, which is interpreted as the packing of procollagen molecules. Between 20 and 30 min, prosecretory and secretory granules respectively became labeled. These results indicate that the cylindrical portions of Golgi saccules transform into prosecretory and subsequently into secretory granules. Within these granules, the parallel threads, believed to be procollagen molecules, are transported to the odontoblast process. At 90 min and 4 h after injection, label was present in predentin, indicating that the labeled content of secretory granules had been released into predentin. This occurred by exocytosis as evidenced by the presence of secretory granules in fusion with the plasmalemma of the odontoblast process. It is proposed that pro-alpha chains give rise to procollagen molecules which assemble into parallel aggregates in the Golgi apparatus. Procollagen molecules are then transported within secretory granules to the odontoblast process and released by exocytosis. In predentin procollagen molecules would give rise to tropocollagen molecules, which would then polymerize into collagen fibrils.


1974 ◽  
Vol 62 (2) ◽  
pp. 449-459 ◽  
Author(s):  
Andrew Churg ◽  
Winston A. Anderson

Synthesis of peroxidase was induced in the uterine epithelium of immature rats by multiple doses over a 24–96-h period of either 17 ß-estradiol, the estrogen-antagonist Parke-Davis CI-628, or a combination of estradiol plus antagonist. Endogenous peroxidase activity first appeared in the cisternae of the rough endoplasmic reticulum of surface epithelial and glandular cells within 24–48 after the initial injection. Uterine peroxidase activity was also visible in the cisternae of the Golgi apparatus, in Golgi-derived secretory granules, and within the uterine and glandular lumen. Some cells of the epithelium produced little or no peroxidase, even after 96 h. Whereas the antagonist appeared to induce synthesis and secretion of peroxidase, neither the antagonist alone nor the combined treatment (estradiol plus antagonist) reproduced the estradiol-mediated growth in organ size and increased lumen diameter.


1971 ◽  
Vol 51 (3) ◽  
pp. 596-610 ◽  
Author(s):  
K. Nakagami ◽  
H. Warshawsky ◽  
C. P. Leblond

The parathyroid glands of young rats were radioautographed after a single injection of the protein precursor tyrosine-3H in the hope of identifying the sites of synthesis and migration of newly formed protein in the gland cells. The same procedure was used after injection of the glycoprotein precursor galactose-3H. As early as 2 min after intravenous injection of tyrosine-3H, the label was mainly found in the rough endoplasmic reticulum suggesting that cisternal ribosomes are sites of protein synthesis. By 5 and 10 min, much of the label had migrated from the rough endoplasmic reticulum into the Golgi apparatus. By 20 and 30 min, some label had migrated from there into secretory granules. By 45 min and 1 hr, the label content of the cell had decreased, indicating release of labeled material outside the cell. At 2 min after intravenous injection of galactose-3H, the label was mainly present in the Golgi apparatus, where presumably galactose is taken up into glycoprotein. By 10 min, some label appeared in secretion granules and by 30 min release of the material to the outside of the cell was under way. In conclusion, it is likely that the tyrosine-labeled protein material consists mainly of the parathyroid hormone. The galactose-labeled carbohydrate material would be either associated with the hormone in the cell or be part of a distinct glycoprotein which may be the one present on the outer surface of the plasma membrane (cell coat).


1962 ◽  
Vol 15 (2) ◽  
pp. 289-312 ◽  
Author(s):  
Edward Essner ◽  
Alex B. Novikoff

The Reuber hepatoma H-35 and Morris hepatoma 5123 have been studied by electron microscopy and by cytochemical staining methods for a number of phosphatases. These studies emphasize the resemblances of the two tumors to rat liver, but they also indicate distinctive features in each of the three tissues. Secretory product accumulates within the cisternae of the Golgi apparatus that dilate to form the Golgi vacuoles. The vacuoles apparently separate, and secretory material undergoes further condensation within them. These "secretory vacuoles" possess acid phosphatase activity and may thus be considered lysosomes. The membranes of the Golgi apparatus are without acid phosphatase activity but show high levels of thiaminepyrophosphatase activity. The endoplasmic reticulum also hydrolyzes thiaminepyrophosphate but at a lower rate; it hydrolyzes the diphosphates of uridine, guanosine, and inosine rapidly. These observations and the electron microscopic images are consistent with the view that the cytomembranes are in a dynamic state of flux, movement, and transformation in the living cell, and that smooth surfaced derivatives of the endoplasmic reticulum become refashioned into the Golgi membranes as the Golgi membranes are being refashioned into those that delimit secretory vacuoles. The variations encountered in the two hepatomas are described. The electron microscope literature dealing with the relations of the Golgi apparatus to secretory granules, on the one hand, and the endoplasmic reticulum, on the other, is reviewed briefly.


1977 ◽  
Vol 74 (2) ◽  
pp. 399-413 ◽  
Author(s):  
AR Hand ◽  
C Oliver

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.


1992 ◽  
Vol 40 (3) ◽  
pp. 257 ◽  
Author(s):  
RC Jones ◽  
M Lin

The genital ducts of Heterodontus portusjacksoni are lined by a ciliated epithelium. In the ductuli efferentes the epithelium is low and contains numerous intraepithelial leucocytes which often contain large dense bodies. All epithelial cells are ciliated and are characterised by apical vesicles, vacuoles and glycogen granules, some rough endoplasmic reticulum, dense bodies and lipid droplets, and a Golgi apparatus. The initial segment of the ductus epididymidis is lined by a very tall epithelium of ciliated and non-ciliated cells. The non-ciliated cells contain numerous apical vesicles, a large Golgi apparatus and numerous mitochondria and secretory granules in close association with an extensive endoplasmic reticulum. The terminal segment of the ductus epididymidis is lined by a low columnar epithelium. A proximal region, occupying part of the head of the epididymis, is similar to the epithelium in the ductuli efferentes. Distally, all the epithelial cells are ciliated. They are characterised by considerable dilated endoplasmic reticulum, a Golgi apparatus, apical vesicles, and numerous mitochondria and secretory granules. The secretory tubules of Leydig's glands are lined by a very tall epithelium with non-ciliated cells containing extensive, dilated, rough endoplasmic reticulum, a large Golgi apparatus, and numerous mitochondria and secretory granules. The significance of the structural differentiation of the duct is discussed in relation to the evolution of the mammalian epididymis.


1926 ◽  
Vol s2-70 (279) ◽  
pp. 419-449
Author(s):  
ROBERT H. BOWEN

As a result of recent studies on secretory synthesis, the following conclusions have been reached : 1. Many gland-cells run through a regular ‘secretory cycle’, beginning with a small cell devoid of secretory granules, progressing through a period in which large numbers of granules are produced and terminating in an act of extrusion of the granules. The cycle may or may not be repeated according to the nature of the cell. 2. The Golgi apparatus is from the beginning present in all kinds of secretory cells, and during the secretory cycle becomes very greatly hypertrophied, establishing a volume in rough relation to that of the secretory products. 3. The topography and behaviour of the apparatus is different in different kinds of glands, but is roughly divisible into three general types characteristic of cells which produce serous, mucous, and lipoidal secretions. 4. The secretory granules make their first appearance only within the area delimited by the Golgi apparatus. 5. In a few cases relations have been made out which indicate that the secretory granules arise in close connexion with the Golgi material. 6. It is concluded that secretory granules are differentiated by the Golgi material, but that no direct transformation of the one into the other occurs such as was claimed by some authors in the case of the mitochondria. 7. It is suggested that the Golgi material is structurally homologous throughout the range of animal cells, and that the so-called idiosomic substance, sometimes associated with it, is to be looked upon as one phase of a duplex system in which the relative development of lipoidal and idiosomic substances may undergo considerable variation. 8. It is suggested that the relation between the Golgi apparatus and secretory granules is homologous to that existing between the Golgi apparatus and the developing acrosome of the animal sperm, and that our rather complete under standing of the latter phenomenon can thus be used as a basis for interpreting the much more obscure phenomena in the gland-cell. 9. No cytological evidence of the origin of secretory products from the nucleus receives any general acceptance at the present time. The nucleus can be considered as the source of secretions only in the indirect sense that it may possibly exercise some control over the process as a whole or may collaborate with other parts of the cell system in preparing materials for the actual synthetic operations of the Golgi apparatus. 10. The establishment of the views here developed must depend finally upon further critical evidence bearing upon the exact relation which exists between individual secretory granules and the Golgi complex.


1926 ◽  
Vol s2-70 (277) ◽  
pp. 75-112
Author(s):  
ROBERT H. BOWEN

Discussion of the results here reported will be postponed to a later paper, pending the completion of two other studies on the Golgi apparatus in gland-cells. But by way of summary, attention may here be called to the following points which in part furnish a general corroboration of the results of other recent work on the Golgi apparatus in gland-cells, and in other respects extend the work of previous writers in a number of directions. 1. In gland-cells of both serous and mucous types, the Golgi material undergoes a very extensive hypertrophy in the earlier stages of the secretory cycle. 2. There is a marked tendency in cells of the serous type for the Golgi apparatus to be extended throughout the mass of developing granules, while in mucous cells the apparatus tends to maintain a more compact and peripheral location. This is apparently correlated with the fact that in mucous cells the secretory granules are completed very soon after their formation, while in serous cells the whole content of granules seems to progress gradually toward a simultaneous completion. 3. The Golgi apparatus in the salivary gland of an invertebrate (Limax) has been shown to consist of the scattered Golgi bodies characteristic of many invertebrate tissues. 4. The topographical and structural differences in the Golgi apparatus of different types of gland-cells have made possible the demonstration that: (a) The demilune cells of the submaxillary gland are distinct from the predominant mucous cells, and indeed are probably of a serous nature. (b) The cells of the pulmonate salivary gland are of two types, mucous and serous, between which, at least in their active stages, no interchangeable relations exist. 5. In all the types of gland-cells examined, a very close topographical relation was found between the Golgi material and the developing secretory granules.


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