scholarly journals Immunocytochemical localization of prorenin, renin, and cathepsins B, H, and L in juxtaglomerular cells of rat kidney.

1989 ◽  
Vol 37 (11) ◽  
pp. 1689-1697 ◽  
Author(s):  
H Matsuba ◽  
T Watanabe ◽  
M Watanabe ◽  
Y Ishii ◽  
S Waguri ◽  
...  

To examine the correlation of localization of prorenin, renin, and cathepsins B, H, and L, immunocytochemistry was applied to rat renal tissue, using a sequence-specific anti-body (anti-prorenin) that recognizes the COOH terminus of the rat renin prosegment. In serial semi-thin sections, immunodeposits for prorenin, renin, and cathepsins B, H, and L were localized in the same juxtaglomerular (JG) cells. Immunodeposits for renin were detected throughout the cytoplasm of the cells, whereas those for prorenin were detected in the perinuclear region. Immunoreactivity for cathepsin B was stronger than that for cathepsins H and L. By electron microscopy, prorenin was localized in small (immature) granules but not in large mature granules, whereas renin was localized mainly in mature granules. In serial thin sections, prorenin, renin, and cathepsin B were colocalized in the same immature granules containing heterogeneously dense material (intermediate granules). By double immunostaining, co-localization of renin with cathepsins B, H, or L was demonstrated in mature granules. The results suggest the possibility that processing of prorenin to renin occurs in immature granules of rat JG cells, and cathepsin B detected in JG cells may be a major candidate for the maturation of renin.

1991 ◽  
Vol 39 (9) ◽  
pp. 1199-1205 ◽  
Author(s):  
Y Uchiyama ◽  
M Nakajima ◽  
T Watanabe ◽  
S Waguri ◽  
N Sato ◽  
...  

We examined by immunocytochemistry the localization of cathepsin B in endocrine cells of rat anterior pituitary lobe, using a monospecific antibody to cathepsin B. By light microscopy, granular immunodeposits for cathepsin B were detected in most endocrine cells of anterior pituitary lobe. Cells immunoreactive for luteinizing hormone (LH) were diffusely immunostained by anti-cathepsin B. By electron microscopy, immunogold particles for cathepsin B were localized in lysosomes of thyrotrophs, somatotrophs, and mammotrophs. In mammotrophs, immunogold particles for cathepsin B were also detected in crinophagic bodies. Double immunostaining co-localized immunogold particles for LH and cathepsin B in secretory granules of gonadotrophs. Immunocytochemistry was also applied to demonstrate localization of renin and prorenin in LH-producing gonadotrophs; immunogold particles for renin were co-localized with those for LH, cathepsin B, or prorenin in their secretory granules. Immunogold particles for prorenin were also co-localized with those for LH or cathepsin B in secretory granules, but prorenin-positive granules appeared less frequently than renin-positive granules. These results suggest that cathepsin B not only plays a role in the protein degradation in lysosomes of anterior pituitary endocrine cells but also participates in the activation of renin in gonadotrophs, as has been demonstrated in secretory granules of juxtaglomerular cells.


1984 ◽  
Vol 32 (6) ◽  
pp. 661-666 ◽  
Author(s):  
R D Dey ◽  
J Hoffpauir

Enterochromaffin (EC) cells in the gastrointestinal tract are known to contain 5-hydroxytryptamine (5HT). The probable ultrastructural localization of 5HT in the dense core vesicles ( DCVs ) of EC cells is based on the use of histochemical techniques, such as argentaffinity and the potassium dichromate reaction. In the present paper we describe an immunocytochemical method for specifically localizing 5HT in EC cells by electron microscopy. Pieces of mucosa from the pyloric region of the rabbit stomach were prepared for electron microscopy by fixation in 0.5% glutaraldehyde-picric acid-formaldehyde without osmication , and then embedded in LX-112. Thick sections (1 micron) were mounted on glass slides and processed for the fluorescence immunocytochemical localization of 5HT. Thin sections (60-90 nm) were mounted on formvar-coated slot grids and processed for the ultrastructural immunocytochemical localization of 5HT. Both the thick and thin sections were processed by an identical procedure, beginning with a 30-min incubation in anti-5HT antiserum diluted 1:1400, followed by an IgG-FITC-gold-labeled second antibody. Fluorescent EC cells were consistently observed in the thick sections of gastric mucosa. By carefully trimming and sectioning the adjacent block face, the identical EC cell could be identified by electron microscopy. A quantitative analysis revealed the number of gold particles in EC cells to be significantly greater over the cores of DCVs than over the non-core cytoplasm or over the nucleus. Absorption of the primary antiserum with 5HT abolished all labeling, while absorption with a 5HT precursor, 5-hydroxytryptophan, did not significantly reduce core labeling. Non-EC epithelial cells were not labeled. These results demonstrate that immunoreactive 5HT in EC cells is stored in the cores of DCVs .


Author(s):  
Keith R. Porter ◽  
Karen L. Anderson

We have shown that a small population of normal cells can be cultured from the scales of the squirrel fish, Holocentrus rufus. They can be grown directly on Formvar-carbon-coated gold grids and, while still on the grids they can be fixed, stained and dehydrated for high voltage electron microscopy. One of the cell types (epidermal) spreads out on the carbon-coated surface and is thin enough in most parts for conventional (100kV) electron microscopy. The aspect of wholeness represented in these qells should not be overlooked for it provides information that might be missed in a series of thin sections where the sample is obviously smaller. Furthermore, if experimental studies are contemplated, they can be made while the cells are still alive and available for light microscopy.


1993 ◽  
Vol 41 (2) ◽  
pp. 273-282 ◽  
Author(s):  
Y Hashizume ◽  
S Waguri ◽  
T Watanabe ◽  
E Kominami ◽  
Y Uchiyama

To further understand the roles of storage granules in parathyroid cells, we examined by immunocytochemistry the localization of cathepsins B and H and of PTH in rat parathyroid gland. In semi-thin sections, small and large granular immunodeposits for cathepsins B and H appeared in the cells, whereas those for PTH were detected throughout the cells, especially in perinuclear regions. By electron microscopy, immunogold particles indicating cathepsins B and H labeled lysosomes and storage granules, whereas those showing PTH were localized in storage granules, small secretory granules, and the trans-Golgi network. Small vesicles labeled by immunogold particles showing these proteinases often appeared close to the storage granules. By double immunostaining, immunogold particles indicating these proteinases were co-localized with those for PTH in storage granules. By EDTA treatment, immunoreactivity for cathepsins B and H and for PTH was notably reduced in the cells, but immunoreactivity for the proteinases was still seen in lysosomes. These results suggest that storage granules in the rat parathyroid cells fuse with small vesicles containing cathepsins B and H, which may participate in regulating the intracellular PTH levels by degrading PTH in the granules.


1986 ◽  
Vol 34 (7) ◽  
pp. 899-907 ◽  
Author(s):  
S Yokota ◽  
H Tsuji ◽  
K Kato

Thin sections of Lowicryl K4M-embedded materials were labeled with protein A-gold complex. Gold particles representing the antigen sites for cathepsin B were exclusively confined to lysosomes of each segment of the nephron. The heaviest labeling was noted in the lysosomes of the S1 segment of the proximal tubules. Labeling intensity varied considerably with the individual lysosomes. Lysosomes of the other tubular segments, such as the S2 and S3 segments of the proximal tubules, distal convoluted tubules, and collecting tubules were weakly labeled by gold particles. Quantitative analysis of labeling density also confirmed that lysosomes in the S1 segment have the highest labeling density and that approximately 65% of labeling in the whole renal segments, except for the glomerulus, was found in the S1 segment. These results indicate that in rat kidney the lysosomes of the S1 segment are a main location of cathepsin B. Further precise observations on lysosomes of the S1 segment revealed that apical vesicles, tubules, and vacuoles were devoid of gold particles, but when the vacuoles contained fine fibrillar materials, gold labeling was detectable in such vacuoles. As the lysosomal matrix becomes denser, the labeling density is increased. Some small vesicles around the Golgi complex were also labeled. These results indicate that the endocytotic apparatus including the apical vesicles, tubules, and vacuoles contains no cathepsin B. When the vacuoles develop into phagosomes, they acquire this enzyme to digest the absorbed proteins.


1986 ◽  
Vol 34 (7) ◽  
pp. 891-897 ◽  
Author(s):  
S Yokota ◽  
H Tsuji ◽  
K Kato

Localization of cathepsin B in rat kidney was studied using immunocytochemical techniques. Cathepsin B was purified from rat liver and antibody to it was raised in rabbits. The antibody reacted with a lysosomal extract of rat kidney to form a single precipitin line in a double-diffusion test. Immunoblot analysis of lysosomal cathepsin B of rat kidney showed two species of 29K and 25K MW. After removal of Epon, semi-thin sections of glutaraldehyde-fixed tissue were stained by the indirect immunoenzyme technique. Dark-brown reaction product, indicating the antigenic sites for cathepsin B, was found in cytoplasmic granules throughout the nephron. Staining intensity and size of the positive granules varied widely in each segment of the nephron. In the glomeruli and distal tubules, a few small cytoplasmic granules were stained. In the proximal tubules, the S1 segment exhibited many large granules which were most heavily stained, whereas the S2 and S3 segments contained few positive granules. All segments of the distal tubules showed the smallest amount of positive granules. A few positive granules were also noted in the cortical and medullary collecting tubules. Control experiments confirmed the specificity of the staining. The results indicate that the major site for cathepsin B in rat kidney is the S1 segment of the proximal tubule which is known to actively take up proteins leaked through the glomerulus.


1989 ◽  
Vol 37 (12) ◽  
pp. 1899-1911 ◽  
Author(s):  
T Watanabe ◽  
S Waguri ◽  
M Watanabe ◽  
Y Ishii ◽  
E Kominami ◽  
...  

We examined the effects of bilateral nephrectomy and colchicine treatment on localization and content of angiotensinogen and cathepsins B, H, and L in rat liver using immunohistochemistry, radioimmunoassay, and enzyme assay. Angiotensinogen content increased in the liver of colchicine-treated rats, whereas a clear-cut increase was not detected in the liver of nephrectomized rats. This tendency was consistent with the immunocytochemical results; only perivenous hepatocytes in control and nephrectomized rats were diffusely immunostained by anti-angiotensinogen, whereas perivenous and periportal hepatocytes of colchicine-treated rats were strongly immunostained. Enzyme assay revealed no significant change in activities of cathepsins B, H, and L in liver extracts under these experimental conditions. Immunocytochemical localization of these cysteine proteinases in hepatocytes after colchicine treatment was more widespread in the cytoplasm than that in the control hepatocytes. By electron microscopy, angiotensinogen was localized in smaller vesicles and some larger vesicles (lysosomes) of hepatocytes after colchicine treatment. Double immunostaining demonstrated co-localization of cathepsins B, H, and L with angiotensinogen in lysosomes. These results suggest that cathepsins B, H, and L play a role in the degradation of excess angiotensinogen in hepatocytes of rats after colchicine treatment.


Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).


Author(s):  
J.R. Walton

In electron microscopy, lead is the metal most widely used for enhancing specimen contrast. Lead citrate requires a pH of 12 to stain thin sections of epoxy-embedded material rapidly and intensively. However, this high alkalinity tends to leach out enzyme reaction products, making lead citrate unsuitable for many cytochemical studies. Substitution of the chelator aspartate for citrate allows staining to be carried out at pH 6 or 7 without apparent effect on cytochemical products. Moreover, due to the low, controlled level of free lead ions, contamination-free staining can be carried out en bloc, prior to dehydration and embedding. En bloc use of lead aspartate permits the grid-staining step to be bypassed, allowing samples to be examined immediately after thin-sectioning.Procedures. To prevent precipitation of lead salts, double- or glass-distilled H20 used in the stain and rinses should be boiled to drive off carbon dioxide and glassware should be carefully rinsed to remove any persisting traces of calcium ion.


Author(s):  
N.C. Lyon ◽  
W. C. Mueller

Schumacher and Halbsguth first demonstrated ectodesmata as pores or channels in the epidermal cell walls in haustoria of Cuscuta odorata L. by light microscopy in tissues fixed in a sublimate fixative (30% ethyl alcohol, 30 ml:glacial acetic acid, 10 ml: 65% nitric acid, 1 ml: 40% formaldehyde, 5 ml: oxalic acid, 2 g: mecuric chloride to saturation 2-3 g). Other workers have published electron micrographs of structures transversing the outer epidermal cell in thin sections of plant leaves that have been interpreted as ectodesmata. Such structures are evident following treatment with Hg++ or Ag+ salts and are only rarely observed by electron microscopy. If ectodesmata exist without such treatment, and are not artefacts, they would afford natural pathways of entry for applied foliar solutions and plant viruses.


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