scholarly journals The Golgi apparatus and GERL during postnatal differentiation of rat parotid acinar cells: an electron microscopic cytochemical study.

1984 ◽  
Vol 32 (5) ◽  
pp. 477-485 ◽  
Author(s):  
A I Doine ◽  
C Oliver ◽  
A R Hand
Keyword(s):  
Young Adult ◽  
Golgi Apparatus ◽  
Secretory Granules ◽  
Acinar Cells ◽  
Sprague Dawley ◽  
Electron Microscopic ◽  
Cytochemical Study ◽  
Parotid Acinar Cells ◽  
Postnatal Differentiation ◽  
Rat Parotid

Morphological and cytochemical changes in the Golgi apparatus and GERL of differentiating parotid acinar cells were examined in Sprague-Dawley rats from 5 days to young adult. At day 5, the Golgi apparatus consisted of 3-6 narrow saccules, with short segments of GERL lying adjacent to the trans Golgi saccule. As the glands matured, the Golgi apparatus increased in size and the saccules became broadened and fenestrated reaching a maximum from days 15-20. The saccules subsequently narrowed slightly and by day 25 resembled those seen in young adults. Numerous cisternae of GERL could be seen at the trans face during this period. While the glands were maturing, marked changes occurred in the distribution of thiamine pyrophosphatase (TPPase) activity in the Golgi saccules. In the immature cells, TPPase activity was restricted to 1 or 2 trans Golgi saccules. However, by day 10 TPPase could also be localized in immature secretory granules and in GERL-like cisternae. Unreactive segments of GERL were also present. This pattern of localization persisted until day 20, after which the TPPase activity in the GERL-like cisternae diminished gradually until by day 40 TPPase again was localized in 1-2 trans Golgi saccules and an occasional immature secretory granule. Acid phosphatase (AcPase) activity was localized primarily in lysosomes in the very young animals and increased in GERL with age up to day 15. From days 15 to 20 there was a decrease in the amount of activity seen in GERL, but from day 20 on, the AcPase activity increased until it reached that seen in young adult animals. These results indicate that the presence of TPPase activity in GERL-like cisternae and immature secretory granules may be dependent upon the developmental as well as the physiologic state of the acinar cells and lend further support to the suggestion that GERL is derived from the trans Golgi saccules.

scholarly journals Effects of secretory stimulation on the Golgi apparatus and GERL of rat parotid acinar cells.

1984 ◽  
Vol 32 (4) ◽  
pp. 403-412 ◽  
Author(s):  
A R Hand ◽  
C Oliver
Keyword(s):  
Golgi Apparatus ◽  
Functional Relationship ◽  
Secretory Granules ◽  
Acinar Cells ◽  
Dynamic Nature ◽  
Parotid Acinar Cells ◽  
Golgi Region ◽  
Thiamine Pyrophosphatase ◽  
Rat Parotid

The structure and cytochemistry of the Golgi apparatus and GERL of rat parotid acinar cells was studied after in vivo secretory stimulation with isoproterenol. Discharge of mature secretory granules was complete within 1 hr after isoproterenol injection, but immature granules in the Golgi region or near the lumen were not released. At early times (1-5 hr) after isoproterenol, acid phosphatase (AcPase) activity was markedly increased in GERL and immature secretory granules compared to uninjected controls. GERL appeared increased in extent and numerous continuities with immature granules were observed. Reaccumulation of mature secretory granules was first evident at 5 hr, and was almost complete by 16 hr after isoproterenol. Thiamine pyrophosphatase (TPPase) activity, normally restricted to the trans Golgi saccules, was frequently present in immature granules during this time. Narrow cisternae resembling GERL, occasionally in continuity with immature granules, also contained TPPase reaction product. By 16-24 hr after stimulation, the activity and distribution of AcPase and TPPase were similar to control cells. These results demonstrate the dynamic nature of the Golgi apparatus and GERL in parotid acinar cells, and emphasize the close structural and functional relationship between these two structures.

scholarly journals Density gradient separation of two populations of lysosomes from rat parotid acinar cells.

1989 ◽  
Vol 37 (11) ◽  
pp. 1645-1652 ◽  
Author(s):  
C Oliver ◽  
R Dromy ◽  
T K Hart
Keyword(s):  
Membrane Fraction ◽  
Secretory Granules ◽  
Succinic Dehydrogenase ◽  
Acinar Cells ◽  
Cell Fractionation ◽  
Marker Enzyme ◽  
Electron Microscopic ◽  
Parotid Acinar Cells ◽  
Rat Parotid ◽  
Secondary Lysosomes

Exocrine acinar cells possess two cytochemically distinct populations of secondary lysosomes. One population is Golgi associated and has demonstrable acid phosphatase (AcPase) activity, whereas the second is basally located and lacks AcPase activity but has trimetaphosphatase (TMPase) activity. The basal lysosomes are tubular in shape and rapidly label with horseradish peroxidase (HRP) after intravenous injection. In the present study using isolated rat parotid acinar cells, the two lysosomal populations were separated by cell fractionation on Percoll density gradients and were analyzed biochemically and by EM cytochemistry. On 35% Percoll gradients, two peaks of AcPase and beta-hexosaminidase, both lysosomal marker enzymes, and succinic dehydrogenase, an enzyme marker for mitochondria, could be resolved. The major peaks of beta-hexosaminidase and succinic dehydrogenase and the minor peak of AcPase corresponded with the dense lysosome fraction. The major peak of AcPase and the minor peaks for beta-hexosaminidase and succinic dehydrogenase coincided with the light membrane fraction. Galactosyl transferase (a marker enzyme for Golgi saccules) and 5'-nucleotidase (a plasma membrane marker) were also associated with this fraction. By electron microscopy, the light membrane fraction was seen to contain tubular elements, multivesicular bodies (MVB), Golgi saccules, GERL, immature secretory granules, and some mitochondria. Electron microscopic cytochemical examination showed that these tubular structures were lysosomes. The dense lysosome fraction contained lysosomes positive for both AcPase and TMPase. After continuous incubation of isolated acinar cells with HRP, reaction product was rapidly localized to the light membrane fraction (greater than 2 min), where it was found in vesicles and tubular lysosomes. By 10 min it was present in MVB and tubular lysosomes, but by 60 min no HRP reaction product had appeared in the dense lysosomes. These results demonstrate that the tubular lysosomes are separable from dense lysosomes, typical secondary lysosomes, and are involved in the initial stages of endocytosis.

scholarly journals Structural Integrity of the Golgi Stack Is Essential for Normal Secretory Functions of Rat Parotid Acinar Cells: Effects of Brefeldin A and Okadaic Acid

2002 ◽  
Vol 50 (12) ◽  
pp. 1611-1623 ◽  
Author(s):  
Hideaki Tamaki ◽  
Shohei Yamashina
Keyword(s):  
Golgi Apparatus ◽  
Okadaic Acid ◽  
Cathepsin D ◽  
Structural Integrity ◽  
Brefeldin A ◽  
Acinar Cells ◽  
Ultrastructural Organization ◽  
Golgi Stack ◽  
Parotid Acinar Cells ◽  
Rat Parotid

We examined the effects of specific inhibitors, brefeldin A (BFA) and okadaic acid (OA), on the ultrastructural organization of the Golgi apparatus and distributions of amylase, Golgi-associated proteins, and cathepsin D in the rat parotid acinar cells. BFA induced a rapid regression of the Golgi stack into rudimentary Golgi clusters composed of tubulovesicules, in parallel with a redistribution of the Golgi-resident proteins and a coat protein (β-COP) into the region of the rough endoplasmic reticulum (rER) or cytosol. The rapid disruption of the Golgi stack could also be induced by the effect of OA. However, redistribution of the Golgi proteins in rER or cytosol could not be observed and β-COP was not dispersed but was retained on the rudimentary Golgi apparatus. These findings suggested that the mechanism of OA in inducing degeneration of the Golgi stack was markedly different from that of BFA. In addition, missorting of amylase, a Golgi protein, and cathepsin D into incorrect transport pathways is apparent in the course of the disruption of the Golgi stack by OA. These Golgi-disrupting effects are reversible and the reconstruction of the stacked structure of the Golgi apparatus started immediately after the removal of inhibitors. In the recovery processes, missorting was also observed until the integrated structure of the Golgi apparatus was completely reconstructed. This suggested that the integrated structure of the Golgi apparatus was quite necessary for the occurrence of normal secretory events, including proper sorting of molecules.

scholarly journals Changes in cell polarity during mitosis in rat parotid acinar cells.

1991 ◽  
Vol 39 (8) ◽  
pp. 1077-1087 ◽  
Author(s):  
H Tamaki ◽  
S Yamashina
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Rough Endoplasmic Reticulum ◽  
Cell Function ◽  
Secretory Granules ◽  
Acinar Cells ◽  
Surface Polarity ◽  
Drug Induced ◽  
Parotid Acinar Cells

We studied the ultrastructure and cytochemistry of mitotic parotid acinar cells in vivo after induction of mitosis by isoproterenol injection. With entrance of the cells into the division cycle, the Golgi apparatus lost its characteristic stacked structure and internal polarity among the cisternae, appearing as fragments distributed throughout the cytoplasm. These fragments consisted of electron-lucent vesiculotubular structures and electron-dense 70-nm vesicles; neither component showed thiamine pyrophosphatase activity, a marker for trans cisternae of the Golgi apparatus, but the 70-nm vesicles showed a positive reaction for osmium impregnation, indicating retention of the cis nature. The rough endoplasmic reticulum was dilated and fragmented. Recovery of the structure of Golgi apparatus and rearrangement of rough endoplasmic reticulum occurred in daughter cells during telophase. These changes were the same as those observed after drug-induced inhibition of protein transport. The secretory granules were not dispersed but were divided into two groups with which centrioles were closely associated. Both groups migrated with the centrioles as far as the next interphase. The distribution of 5'-nucleotidase on the luminal plasma membrane showed no change during the process of division, thus demonstrating that surface polarity was maintained during mitosis. These changes in organelle structure and distribution may be due to the conversion of cell function from a secretory to a mitotic action.

beta 1- and beta 2-adrenoceptor agonists have different effects on rat parotid acinar cells

1982 ◽  
Vol 242 (5) ◽  
pp. G481-G485 ◽  
Author(s):  
R. Henriksson
Keyword(s):  
Acinar Cells ◽  
Beta Agonist ◽  
Sprague Dawley ◽  
Camp Content ◽  
Amylase Release ◽  
Parotid Acinar Cells ◽  
Beta 2 ◽  
Rat Parotid

To determine whether beta 1- and beta 2-adrenoceptors have similar functions in salivary glands, Sprague-Dawley rats were chronically treated with either the beta 1-selective (prenalterol), beta 2-selective (terbutaline), or the nonselective beta-agonist isoproterenol. All three agonists increased parotid and submandibular gland weight and acinar cell size. Isoproterenol and prenalterol caused marked quantitative and qualitative alterations in the granule population, whereas terbutaline had no effect. A single injection of isoproterenol caused a significant amylase release and accumulation of cAMP. Prenalterol was as potent as isoproterenol with regard to amylase release but was without effect on the cAMP content. In contrast, terbutaline had a minimal effect on amylase release but had the same effect as isoproterenol on cAMP accumulation. The in vitro perifusion experiments confirmed these in vivo results with respect to the effects of the selective beta-agonists. Thus, the present investigation using both morphological and biochemical methods suggests that beta 1- and beta 2-adrenoceptors may have different functions in rat parotid acinar cells. In addition, the stimulus-growth coupling seems to be unrelated to stimulus-secretion coupling.

scholarly journals Enzyme modulation of the Golgi apparatus and GERL: a cytochemical study of parotid acinar cells.

1983 ◽  
Vol 31 (8) ◽  
pp. 1041-1048 ◽  
Author(s):  
C Oliver ◽  
A R Hand
Keyword(s):  
Enzyme Activity ◽  
Secretory Granule ◽  
Secretory Granules ◽  
Acinar Cells ◽  
Enzyme Localization ◽  
Cytochemical Study ◽  
Postnatal Maturation ◽  
Parotid Acinar Cells ◽  
Enzyme Modulation ◽  
Thiamine Pyrophosphatase

The distribution of thiamine pyrophosphatase (TPPase) and acid phosphatase (AcPase) has been examined in resting parotid acinar cells as well as during decreased and increased secretory granule production. In resting acinar cells, TPPase activity was restricted to the trans Golgi saccules and AcPase activity was localized in GERL and immature secretory granules. Although secretory granule production is diminished during ethionine intoxication, no significant alteration in the distribution of either TPPase or AcPase was noted. However, marked changes in enzyme localization, especially of TPPase, occurred during accelerated secretory granule production. The alterations were essentially the same for all of the conditions studied (recovery from ethionine treatment, recovery from a protein depletion diet, secretory stimulation with isoproterenol, and postnatal maturation of the parotid gland). During maximal secretory granule production, TPPase activity was localized not only in the trans Golgi saccules, but also in GERL-like cisternae and immature secretory granules. The immature secretory granules were often in continuity with the GERL-like cisternae. At the same time that the TPPase activity was increased, the AcPase activity was frequently diminished. These modulations in enzyme activity provide evidence that GERL is derived from the trans Golgi saccule.

Secretory proteins without a transport signal are retained in secretory granules during maturation in rat parotid acinar cells

2015 ◽  
Vol 60 (4) ◽  
pp. 642-649 ◽  
Author(s):  
Osamu Katsumata-Kato ◽  
Megumi Yokoyama ◽  
Miwako Matsuki-Fukushima ◽  
Takanori Narita ◽  
Hiroshi Sugiya ◽  
...  
Keyword(s):  
Secretory Granules ◽  
Acinar Cells ◽  
Secretory Proteins ◽  
Parotid Acinar Cells ◽  
Rat Parotid

Ultrastructure of Mitotic Arrest Induced by Isoprenaline in Rat Parotid Acinar Cells

1974 ◽  
Vol 16 (2) ◽  
pp. 309-331
Author(s):  
J. M. RADLEY
Keyword(s):  
Secretory Granules ◽  
Acinar Cells ◽  
Ultrastructural Level ◽  
Mitotic Arrest ◽  
Metaphase Arrest ◽  
Parotid Acinar Cells ◽  
Large Size ◽  
G2 Phase ◽  
Rat Parotid ◽  
Cell Centre

The mitotic arrest of acinar cells in the rat parotid gland in response to isoprenaline has been investigated at the ultrastructural level. The arrested cells were characterized by the presence of both centriole pairs at the cell centre, around which chromosomes formed an approximately spherical array. Microtubules radiated out from both centriole pairs, indicating that they were part of a bipolar system. The microtubule population included both non-kinetochore and kinetochore microtubules. Metaphase arrest appeared to be due to failure of the poles to separate, or to remain separated in the case of cells already in metaphase at the time of drug administration. This could be explained by the drug interfering with the ability of interpolar microtubules from opposite poles to interact with one another. The distribution of the chromosomes around the centrioles appears to depend on the presence of kinetochore microtubules, which are thought to act as tethers, either by themselves or in conjunction with non-kinetochore microtubules. It is suggested that tension is necessary between the kinetochores and poles to attain the arrest configuration. Chromosomes were observed in which both kinetochores had attached microtubules but whether or not they were linked to opposite poles remains to be investigated. Two types of arrested cell were distinguished by their content of secretory granules. Cells already in mitosis at the time of isoprenaline administration were not depleted by drug action, and during the period of arrest numerous large secretory granules were intermingled with the chromosomes. Those cells which entered mitosis after the drug was given were initially blocked in the G2 phase, during which time they were depleted of secretory granules. On entering mitosis, these cells possessed only small secretory granules, which were newly synthesized. In the metaphase-arrested state the small secretory granules were clustered around the centriolar complexes, demonstrating the presence of a poleward force operating on them. It is possible that the same force acts on the secretory granules in the first type of arrested cell, but because of the relatively large size of the granules, the clustering around the poles is not pronounced. The nature of the forces acting on the chromosomes and on the secretory granules is discussed. The functioning of these forces during the arrest state has to be considered in any general model for mitosis.

scholarly journals Electron Microscopic Evidence Suggesting Secretory Granule Formation within the Golgi Apparatus

1957 ◽  
Vol 3 (2) ◽  
pp. 319-322 ◽  
Author(s):  
Marilyn G. Farquhar ◽  
S. Robert Wellings
Keyword(s):  
Golgi Apparatus ◽  
Secretory Granule ◽  
Secretory Granules ◽  
Acinar Cells ◽  
Secretory Activity ◽  
Pancreatic Acinar Cells ◽  
Electron Microscopic ◽  
Granule Formation ◽  
Golgi Bodies ◽  
Rat Pituitary

Secretory granules have been seen within components of the Golgi bodies of rat pituitary acidophils and mouse pancreatic acinar cells. The fact that secretory granules are much more frequently encountered within Golgi components under conditions of increased secretory activity suggests that granule formation may occur within the Golgi apparatus in these two types of cells.

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