An Electron Microscopical Study of Neutral Red Granules in Mouse Exocrine Pancreas

1964 ◽  
Vol s3-105 (70) ◽  
pp. 219-226
Author(s):  
JENNIFER M. BYRNE

The neutral red granule cycle in the mouse exocrine pancreas was studied with the electron microscope in order to discover what changes appear at an ultrastructural level in cells treated with neutral red. There are no changes in the endoplasmic reticulum, the nucleus, the Golgi apparatus, the zymogen granules, or the mitochondria of stained cells when compared with normal tissue. Osmiophil inclusions are found which in their size and distribution correspond to the neutral red granules seen under the light microscope. Such inclusions are not seen in normal tissue. They resemble morphologically the lysosomes of various tissues.

1969 ◽  
Vol 43 (2) ◽  
pp. 289-311 ◽  
Author(s):  
P. Whur ◽  
Annette Herscovics ◽  
C. P. Leblond

Rat thyroid lobes incubated with mannose-3H, galactose-3H, or leucine-3H, were studied by radioautography. With leucine-3H and mannose-3H, the grain reaction observed in the light microscope is distributed diffusely over the cells at 5 min, with no reaction over the colloid. Later, the grains are concentrated towards the apex, and colloid reactions begin to appear by 2 hr. With galactose-3H, the reaction at 5 min is again restricted to the cells but it consists of clumped grains next to the nucleus. Soon after, grains are concentrated at the cell apex and colloid reactions appear in some follicles as early as 30 min. Puromycin almost totally inhibits incorporation of leucine-3H and mannose-3H, but has no detectable effect on galactose-3H incorporation during the 1st hr. Quantitation of electron microscope radioautographs shows that mannose-3H label localizes initially in the rough endoplasmic reticulum, and by 1–2 hr much of this reaction is transferred to the Golgi apparatus. At 3 hr and subsequently, significant reactions are present over apical vesicles and colloid, while the Golgi reaction declines. Label associated with galactose-3H localizes initially in the Golgi apparatus and rapidly transfers to the apical vesicles, and then to the colloid. These findings indicate that mannose incorporation into thyroglobulin precursors occurs within the rough endoplasmic reticulum; these precursors then migrate to the Golgi apparatus, where galactose incorporation takes place. The glycoprotein thus formed migrates via the apical vesicles to the colloid.


1964 ◽  
Vol 20 (3) ◽  
pp. 473-495 ◽  
Author(s):  
Lucien G. Caro ◽  
George E. Palade

The synthesis, intracellular transport, storage, and discharge of secretory proteins in and from the pancreatic exocrine cell of the guinea pig were studied by light- and electron microscopical autoradiography using DL-leucine-4,5-H3 as label. Control experiments were carried out to determine: (a) the length of the label pulse in the blood and tissue after intravenous injections of leucine-H3; (b) the amount and nature of label lost during tissue fixation, dehydration, and embedding. The results indicate that leucine-H3 can be used as a label for newly synthesized secretory proteins and as a tracer for their intracellular movements. The autoradiographic observations show that, at ∼5 minutes after injection, the label is localized mostly in cell regions occupied by rough surfaced elements of the endoplasmic reticulum; at ∼20 minutes, it appears in elements of the Golgi complex; and after 1 hour, in zymogen granules. The evidence conclusively shows that the zymogen granules are formed in the Golgi region by a progressive concentration of secretory products within large condensing vacuoles. The findings are compatible with an early transfer of label from the rough surfaced endoplasmic reticulum to the Golgi complex, and suggest the existence of two distinct steps in the transit of secretory proteins through the latter. The first is connected with small, smooth surfaced vesicles situated at the periphery of the complex, and the second with centrally located condensing vacuoles.


1980 ◽  
Vol 210 (1179) ◽  
pp. 211-234 ◽  

The postnatal development of the lateral geniculate nucleus has been studied quantitatively with the electron microscope in normal kittens and in kittens with eyelid closure. The maturation of the synaptic organization of glomeruli in the normal kitten occurs during the period of susceptibility to eyelid closure and is due predominantly to a logarithmic increase in the number of symmetric presynaptic dendritic synapses. In contrast, the pro­portion of symmetric synapses falls with age in non-glomerular neuropil over this period. Unilateral and bilateral eyelid suture do not interfere with the normal development of the lateral geniculate nucleus.


1980 ◽  
Vol 28 (3) ◽  
pp. 231-237 ◽  
Author(s):  
R S Decker ◽  
M L Decker ◽  
A R Poole

Lysosomal cathepsin D has been localized with the electron microscope employing an indirect immunohistochemical method using peroxidase labeled, monospecific antibody Fab' subunits. The acid proteinase has been demonstrated within secondary lysosomes of cardiac myocytes and interstitial cells, but not in components of the Golgi apparatus or endoplasmic reticulum. Incubations with a variety of peroxidatic inhibitors suggests that the staining that is observed in secondary lysosomes is attributable to the peroxidase-labeled antibody and not to endogenous oxidation of DAB. The protocol outlined here provides a reproducible method to localize the major lysosomal acid proteinase of the heart at the subcellular level.


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.


1971 ◽  
Vol 68 (1_Suppl) ◽  
pp. S190-S204 ◽  
Author(s):  
Paul K. Nakane

ABSTRACT Hormones were localized immunoenzymocytochemically at the ultrastructural level directly on ultrathin sections of anterior pituitary glands of rats which had been fixed and embedded in either methacrylate or Epon. GH, LTH, ACTH and LH are best localized on methacrylate embedded glands and GH and LTH on Epon embedded glands. GH and LTH were found in secretion granules, and depending on the activity of the cells, the hormones could be found in the Golgi apparatus and in the cisternae of endoplasmic reticulum. The grids on which hormones have been localized may also be processed for electron radioautography, an approach particularly useful to study simultaneously substrate uptake as well as product synthesis.


1964 ◽  
Vol s3-105 (71) ◽  
pp. 343-348
Author(s):  
JENNIFER M. BYRNE

The Gomori test for acid phosphatase was performed on pancreatic tissue from mice injected with neutral red. On an electron microscopical level, acid phosphatase activity was found to be localized in the neutral red granules. It is suggested that the neutral red granules are of lysosomal derivation.


1971 ◽  
Vol 51 (1) ◽  
pp. 1-NP ◽  
Author(s):  
ELENA BIANCHI ◽  
W. PIERPAOLI ◽  
E. SORKIN

SUMMARY A detailed light and electron microscope examination of the anterior pituitary gland of mice at different times after neonatal thymectomy was performed. Neonatal removal of the thymus resulted in a progressive increase in the number of somatotrophic hormone-producing cells showing characteristic changes represented by extremely distended cisternae of the endoplasmic reticulum and reduction in the number of hormone granules. These modifications were not observed in sham-operated controls or in neonatally splenectomized mice. The functional significance of these changes in relation to thymectomy and the significance of somatotrophic hormone for the development of the thymus and for immunological maturation is discussed. It is suggested that somatotrophic hormone and possibly other hormones determine certain specific steps of differentiation of precursor cells to immunocompetent cells and that the thymus is an endocrine target gland of somatotrophic hormone.


1961 ◽  
Vol 9 (4) ◽  
pp. 825-839 ◽  
Author(s):  
Edward J. Reith

Ameloblasts from different regions of upper incisors of rats were examined with the electron microscope. During matrix formation, the cells resemble secretory cells. They are extremely long, tightly packed, and show considerable polarity. Nuclei are at the basal end of the cell. Mitochondria are proximal and the Golgi apparatus distal to the nucleus. Ergastoplasm is found in all levels but mainly in the distal end. A terminal bar apparatus separates the distal end of the cell from Tomes's process. Next to this is soft enamel. The next incisal region is a transitional zone in which the ameloblasts separate easily from the enamel. Endoplasmic reticulum is dilated and very obviously in communication with the perinuclear space. Mitochondria are present not only proximal, but also distal, to the nucleus. The next incisal zone consists of cells related to the maturation of enamel. They no longer resemble secretory cells, but now have more characteristics of transporting cells. Processes from the distal end of the cell are present with mitochondria closely applied to the base of the processes. A considerable amount of intercellular space exists with microvilli projecting into the space. Iron granules appear in these cells, and the ergastoplasmic cisternae are dilated. In the incisal end of this zone, the iron granules form aggregates. The iron finally leaves the cells to enter the enamel. Free RNP particles and fibrils become more evident after the iron leaves the cells. In the most incisal region, the ameloblasts are further reduced in height. Distal processes are no longer present and fibrils are more conspicuous.


1975 ◽  
Vol 67 (2) ◽  
pp. 320-344 ◽  
Author(s):  
B Meyrick ◽  
L Reid

Incorporation of [3H]threonine and [3H]glucose by the mucous and serous cells of the human bronchial submucosal gland has been studied over 8 h using, for the first time in vitro pulse labeling and electron microscope autoradiography. In assessing the autoradiographs, two methods were compared, the circle analysis and the recently described hypothetical grain analysis. Preliminary studies showed formaldehyde to be the most suitable fixative. Chemical analysis of tissue revealed that [3H]threonine was incorporated into the polypeptide moiety of the bronchial gland product and that metabolites of [3H]-glucose were incorporated into the carbohydrate. Tritiated threonine was first localized in the endoplasmic reticulum of both mucous and serous cells and later migrated to the Golgi apparatus, while metabolites of [3H]glucose localized first mainly in the Golgi apparatus. From here, both radioactive precursors were next identified in vacuoles and, finally, in secretory granules. The mucous cell incorporated strikingly more of both radioactive precursors than the serous cell. Thus, it seems that oligosaccharides of mucous and serous cell glycoproteins are synthesized mainly in the Golgi apparatus and added there to the polypeptide core which is synthesized in the endoplasmic reticulum. The relationship of the mucous cell to the serous cell is discussed. It seems that under "normal" conditions each cell represents a different line but that injury may transform a serous cell into a mucous cell.


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