scholarly journals Light and electron microscopic localization of ACTH and pro-opiomelanocortin-derived peptides in human developmental and neoplastic cells.

1984 ◽  
Vol 32 (8) ◽  
pp. 885-893 ◽  
Author(s):  
R Y Osamura ◽  
Y Tsutsumi ◽  
K Watanabe

Oncofetal aspects of ACTH and pro-opiomelanocortin (POMC)-derived peptides were studied immunohistochemically at the light and electron microscopic level in human fetal pituitary glands, pituitary adenomas, and small-cell carcinoma of the lung. ACTH, beta-endorphin, and gamma-MSH were localized in the same cells of both fetal and adult pituitary, as well as in the above-mentioned neoplastic tissues. However, alpha-MSH was observed only in the early fetal pituitary, its concentration decreasing with advancing gestational age. The adult pituitary contained only a few alpha-MSH-positive cells. By immunoelectron microscopy, ACTH in the adult pituitary was localized exclusively in the secretory granules. In fetal pituitary at 9 weeks' gestation, ACTH was localized in the perinuclear spaces (PNS), cisternae of rough endoplasmic reticulum (RER), Golgi saccules, and secretory granules. The staining pattern of ACTH in these organelles varied from cell to cell. In fetal pituitaries of greater gestational ages, ACTH was localized in secretory granules. The pituitary adenomas mimicked the staining characteristics of the adult pituitary, i.e., negative or only very occasional alpha-MSH staining and localization of ACTH in the secretory granules. The ectopic ACTH-producing tumors showed a staining pattern similar to that of the early fetal pituitary, i.e., positive staining for alpha-MSH and the presence of ACTH in PNS and cisternae of RER.

2003 ◽  
Vol 51 (1) ◽  
pp. 31-39 ◽  
Author(s):  
Toshihiro Takizawa ◽  
Clark L. Anderson ◽  
John M. Robinson

Adequate contrast of ultrathin cryosections is crucial for evaluating morphological detail to assess immunocytochemical localization at the electron microscopic level. We have developed a positive staining method for achieving contrast in ultrathin cryosections, from tissue fixed only in paraformaldehyde, that provides excellent contrast at the electron microscopic level.


1978 ◽  
Vol 89 (3) ◽  
pp. 521-529 ◽  
Author(s):  
D. J. McComb ◽  
K. Kovacs

ABSTRACT Fifteen sparsely granulated prolactin-producing adenomas and 10 non-tumourous adenohypophyses, removed by surgical hypophysectomy, have been studied using morphometry at the electron microscopic level. Compared to non-tumourous prolactin cells, sparsely granulated adenomatous prolactin cells showed a significant decrease in diameter and volume density of secretory granules and an increased volume density of rough-surfaced endoplasmic reticulum and Golgi apparatus. The volume density of mitochondria remained unchanged. These results indicate that the cells of the adenoma are in a highly active functional state. It appears that the equilibrium between hormone synthesis, storage and release is altered in adenomatous prolactin cells.


1980 ◽  
Vol 28 (10) ◽  
pp. 1113-1118 ◽  
Author(s):  
T Tanaka ◽  
E W Gresik ◽  
A M Michelakis ◽  
T Barka

By using antibodies against highly purified submandibular gland renin, renin was localized immunocytochemically at the light and electron microscopic level in the submandibular glands and kidneys of adult male SWR/J and C57BL/6J mice. In accord with the data of Wilson et al. (Proc Natl Acad Sci USA 75:1185, 1977), renin was demonstrable only in the submandibular glands of SWR/J mice (high strain), where it was confined to the secretory granules of the granular convoluted tubules. In the kidneys of both strains, renin was confined to epithelioid cells of the juxtaglomerular apparatus. Electron microscopically immunostaining was restricted to the granules of the juxtaglomerular epitheliod cells. Morphometric analyses suggested that the kidney of the C57BL/6J mice contained more immunoreactive complexes per unit volume of cortex than SWR/J mice kidney. The data indicate that submandibular gland renin cross-reacts with kidney renin, but that genetic controls of these polypeptides in the two organs are independent.


1982 ◽  
Vol 30 (7) ◽  
pp. 682-690 ◽  
Author(s):  
I M Varndell ◽  
F J Tapia ◽  
J De Mey ◽  
R A Rush ◽  
S R Bloom ◽  
...  

Enkephalin-like immunoreactivity has been localized to electron-dense secretory granules of cat and piglet carotid bodies and adrenal medullae, horse adrenal medulla, and also to human adrenal medulla and pheochromocytomas using a gold-labeled antibody technique performed at the electron microscopic level. The same granules were also demonstrated to exhibit dopamine-beta-hydroxylase-like immunoreactivity, which suggests a granular colocalization of amines and peptides in catecholamine-storing cells.


1993 ◽  
Vol 41 (5) ◽  
pp. 777-782 ◽  
Author(s):  
L C Schmued ◽  
L F Snavely

Fluoro-Ruby, the fluorescent tetramethylrhodamine-dextran-amine used to demonstrate anterograde axon transport, has been successfully photoconverted and subsequently localized by electron microscopy. The photoconversion was accomplished by irradiating the tissue with green light while bathing it in a solution containing DAB. The tissue could then be examined by brightfield microscopy or processed for conventional electron microscopy. Potential advantages of the technique include greater permanence and contrast at the light microscopic level and the ability to resolve synaptic connectivity at the electron microscopic level.


1972 ◽  
Vol 20 (12) ◽  
pp. 969-974 ◽  
Author(s):  
JOSEPH E. MAZURKIEWICZ ◽  
PAUL K. NAKANE

Tissues embedded in polyethylene glycol (PEG) were used for the immunocytochemical localization of cellular antigens at the light and electron microscopic level. For demonstration of the method, growth hormone and luteinizing hormone were localized in the anterior pituitary gland of the rat embedded in PEG, using peroxidase-labeled antibodies. PEG is water-soluble, has a low melting temperature yet is firm enough to be sectioned at room temperature. Preservation of cellular ultrastructure is good. The use of PEG-embedded tissue permits precise correlation of light and electron microscopic observations of the same tissue section.


1978 ◽  
Vol 26 (10) ◽  
pp. 855-861 ◽  
Author(s):  
E Gresik ◽  
A Michelakis ◽  
T Barka ◽  
T Ross

Renin was localized in the submandibular gland of the adult mouse at light and electron microscopic levels by the unlabeled antibody enzyme method of Sternberger. At the light microscopic level, renin was confined to the granular convoluted tubule (GCT) segment of the gland with considerable variation among GCT cells in intensity of staining. Some GCT cells failed to stain for renin. The pattern of staining was the same in the gland of male and female mice, but in the glands of females GCT segments were smaller and less numerous. At the electron microscopic level, staining for renin was also confined to the GCT cells, and was localized exclusively to the secretory granules. The intensity of staining of the secretory granules within a given GCT cell varied; some cells contained only minimally reactive or negative secretory granules. All other organelles within the GCT cell, except condensing vacuoles, failed to stain.


1992 ◽  
Vol 40 (2) ◽  
pp. 265-274 ◽  
Author(s):  
M T Castells ◽  
J Ballesta ◽  
J F Madrid ◽  
J A Martínez-Menárguez ◽  
M Avilés

We investigated the glycoconjugates of the human bronchial glands at light and electron microscopic level by means of lectin histochemistry in combination with neuraminidase digestion and beta-elimination reaction. Both direct and indirect techniques using lectin-peroxidase, lectin-gold, and glycoprotein-gold complexes were applied. The binding pattern of the six lectins (ConA, HPA, DSA, WGA, LEA, and PNA) used in the present study suggests that mucous and serous cells of human bronchial glands contain both N- and O-glycosylated proteins in the secretory granules. Asparagine-linked oligosaccharides containing Gal(beta-1,4) GlcNAc and Man residues were abundant in serous cells. The demonstration of both the terminal Neu 5Ac (alpha-2,3, or 6) Gal (beta-1,4) GlcNAc sequence in the N-linked oligosaccharides of mucous cells and the terminal disaccharide Gal (beta-1,4) GlcNAc in the N-linked oligosaccharide chains of serous cells suggests the existence of complex type sugar chains N-glycosidically linked to the peptide region of the glycoproteins. The binding pattern of the DSA and the neuraminidase-DSA sequence provides evidence for the existence of sialyltransferase activity in the forming mucous granules of mucous bronchial cells.


2020 ◽  
Vol 21 (3) ◽  
pp. 761 ◽  
Author(s):  
Heinz Schwarz ◽  
Werner Hoffmann

The TFF peptides xP1 and xP4 from Xenopus laevis are orthologs of TFF1 and TFF2, respectively. xP1 is secreted as a monomer from gastric surface mucous cells and is generally not associated with mucins, whereas xP4 is a typical secretory peptide from esophageal goblet cells, and gastric mucous neck and antral gland cells tightly associated as a lectin with the ortholog of mucin MUC6. Both TFF peptides have diverse protective functions, xP1 as a scavenger for reactive oxygen species preventing oxidative damage and xP4 as a constituent of the water-insoluble adherent inner mucus barrier. Here, we present localization studies using immunofluorescence and immunoelectron microscopy. xP1 is concentrated in dense cores of secretory granules of surface mucous cells, whereas xP4 mixes with MUC6 in esophageal goblet cells. Of note, we observe two different types of goblet cells, which differ in their xP4 synthesis, and this is even visible morphologically at the electron microscopic level. xP4-negative granules are recognized by their halo, which is probably the result of shrinkage during the processing of samples for electron microscopy. Probably, the tight lectin binding of xP4 and MUC6 creates a crosslinked mucous network forming a stabile granule matrix, which prevents shrinkage.


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