scholarly journals GLOMERULAR PERMEABILITY

1969 ◽  
Vol 130 (2) ◽  
pp. 381-399 ◽  
Author(s):  
M. A. Venkatachalam ◽  
Morris J. Karnovsky ◽  
Ramzi S. Cotran
Keyword(s):  
Epithelial Cells ◽  
Basement Membrane ◽  
Intercellular Junctions ◽  
Ultrastructural Localization ◽  
Basement Membranes ◽  
The Other ◽  
Serial Sections ◽  
Renal Glomerulus ◽  
Glomerular Permeability ◽  
Urinary Space

Wistar/Furth rats were made nephrotic by daily administration of amino-nucleoside of puromycin, and the ultrastructural localization of horseradish peroxidase (mol wt 40,000) in the renal glomerulus was studied from 1 min to 20 hr after intravenous injection of the tracer. In control rats, peroxidase permeated the endothelial fenestrae, the basement membrane, and the epithelial slits, and was present in tubular lumina. Nephrotic glomeruli showed relatively normal basement membranes, extensive fusion of foot processes with formation of "close" intercellular junctions, and large vacuoles and pockets in epithelial cells. On serial sections some of the epithelial vacuoles communicated on one side with the extracellular space overlying basement membrane, and on the other side with the urinary space. In nephrotic animals, peroxidase permeated the basement membrane and the close junctions, and was present in many of the vacuoles and pockets as early as 1 min after injection. Only small numbers of peroxidase-positive vacuoles remained in. epithelial cells 1 hr or more after injection of the tracer. It is suggested that the epithelial pockets and vacuoles form pathways across which leaking proteins can be transferred across the epithelium into the urinary space. Epithelial vacuoles may also be absorption droplets designed to "conserve" leaking proteins, but this function was not prominent in our experiments with peroxidase.

scholarly journals AN ULTRASTRUCTURAL STUDY OF GLOMERULAR PERMEABILITY IN AMINONUCLEOSIDE NEPHROSIS USING CATALASE AS A TRACER PROTEIN

1970 ◽  
Vol 132 (6) ◽  
pp. 1168-1180 ◽  
Author(s):  
M. A. Venkatachalam ◽  
R. S. Cotran ◽  
M. J. Karnovsky
Keyword(s):  
Epithelial Cells ◽  
Basement Membrane ◽  
Ultrastructural Study ◽  
Glomerular Permeability ◽  
Beef Liver ◽  
Ultrastructural Cytochemistry ◽  
Slit Pore ◽  
Slit Pores ◽  
Urinary Space ◽  
Aminonucleoside Nephrosis

Beef liver catalase (mol wt 240,000) was injected intravenously into normal rats and rats made nephrotic with aminonucleoside of puromycin. The localization of the tracer in the kidneys was then studied by ultrastructural cytochemistry, 3 min–12 hr after injection. Passage of catalase into the urinary space in normal rats was restricted by the basement membrane and by the epithelial slit pore. Nephrotic glomeruli showed extensive fusion of foot processes and formation of pockets and vacuoles in the fused epithelium; within 3 min after injection, catalase appeared in basal pockets, epithelial vacuoles, and the urinary space. Residual slit pores and close junctions in fused epithelium were impermeable to catalase. These studies indicate that alteration of the epithelial cells and basement membrane is responsible for protein leakage in aminonucleoside nephrosis.

scholarly journals Die Kaliumhydrogenphosphat-induzierte Nephropathie des Hundes. I. Pathogenese der Tubulusatrophiee [Potassium Hydrogen Phosphate Induced Nephropathy in the Dog. I. Pathogenesis of Tubular Atrophy—author's trans.]

1980 ◽  
Vol 17 (6) ◽  
pp. 699-719 ◽  
Author(s):  
P. Schneider ◽  
G. Pappritz ◽  
R. Müller-Peddinghaus ◽  
M. Bauer ◽  
H. Lehmann ◽  
...  
Keyword(s):  
Acid Phosphatase ◽  
Epithelial Cells ◽  
Basement Membrane ◽  
Basement Membranes ◽  
Tubular Epithelial Cells ◽  
Beagle Dogs ◽  
Lysosomal Degradation ◽  
Tubular Basement Membrane ◽  
Tubular Atrophy ◽  
Study Results

A nephropathy with severe tubular atrophy was observed in Beagle dogs after oral administration of K2HPO4 for 14 or 38 weeks. We describe the complete lysosomal degradation of atrophying tubular epithelial cells. During two experiments of 14 and 38 weeks duration, respectively, a total of 15 Beagle dogs received 0.8 g K2HPO4/kg body weight daily with their food. All dogs were examined clinically at regular intervals. Renal biopsies were taken in the fourth week from beagles of the 14-week study. Results were compared with those of control dogs. At the end of the experiments the animals were killed and necropsies done. Different stains and histochemical reactions were applied to paraffin sections of the kidneys. Acid phosphatase and β-glucuronidase were found on cryostat sections. Kidneys fixed by perfusion of five Beagles from the 38-week study and three Beagles of the 14-week study, and from five control dogs, were examined electron microscopically. Ultrahistochemically, acid phosphatase was demonstrated. Clinically, the dogs in both experiments vomited, were cachectic, and had elevated creatinine and blood urea nitrogen. Morphologically, qualitatively identical changes were seen, but the renal damage was most marked at 38 weeks. There were disseminated tubular atrophy (usually of the proximal tubules), focal scar tissue and nephrocalcinosis. The following pathogenesis was established for the lesions of the proximal tubule: Tubular atrophy begins with loss of differentiation of epithelial cells. Enzyme histochemistry, ultrahistochemistry and electron microscopy show an increase in autophagic vacuoles and autophagolysosomes. The lysosomal bodies showing fusion enclose large parts of the cytoplasm as the process continues. Complete lysosomal degradation of epithelial cells and extrusion of large lysosomes into the tubular lumen follow. After complete enzymatic digestion of the intratubular detritus, the residue is empty, convoluted and collapsed tubular basement membrane. Atrophic tubular epithelial cells have many organelle-free zones at their base, which contain fine filamentous material resembling that of the basement membrane. The degradation processes described here may explain why clinically the urinary sediment contains few cylinders and epithelial cells and why proteinuria decreases significantly toward the end of the experiment. So far, it is not clear whether the tubular basement membrane is synthesized by the tubular cells, by fibroblasts or by both cell types. The presence of basement membrane-like material in tubular epithelial cells and in parietal epithelial cells of the glomerulus favors the view that epithelial cells produce the basement membranes and that increased production of basement membrane-like material is a sign of loss of differentiation.

Reabsorption of native and glycated albumin by renal proximal tubular epithelial cells

1996 ◽  
Vol 271 (2) ◽  
pp. F261-F268 ◽  
Author(s):  
M. Bendayan ◽  
I. Londono
Keyword(s):  
Epithelial Cells ◽  
Glomerular Filtration ◽  
Glycated Albumin ◽  
Basement Membranes ◽  
Endocytic Pathway ◽  
Tubular Epithelial Cells ◽  
Proximal Tubular Epithelial Cells ◽  
Proximal Tubular ◽  
Renal Proximal Tubular ◽  
Urinary Space

The proximal tubule epithelial handling of native and glycated albumin was evaluated by quantitative immunocytochemistry. Native bovine serum albumin (BSA) and its glycated form (gBSA), tagged to different haptens, were simultaneously injected in anesthetized mice and maintained in circulation for 10 or 60 min. Both albumins were localized within the capillary lumen, in glomerular and peritubular basement membranes, the urinary space, and cellular compartments of the proximal tubular epithelial cells. In these cells, both forms of albumin were concomitantly found within the same endocytic-lysosomal system. Morphometric evaluations have indicated higher proportions of gBSA in the urinary space, reflecting probably a significant glomerular filtration of this form of albumin combined to a lesser reabsorptive clearance. Indeed, higher proportions of native BSA were found in the endocytic compartment of the tubular epithelial cells, suggesting its preferential reabsorption. The present study thus supports a preferential glomerular filtration of gBSA with a facilitated filtration of native BSA in the presence of the glycated one. It also demonstrates the tubular reabsorption of BSA and gBSA through a common endocytic pathway, in which the native BSA is preferentially reabsorbed with respect to its glycated form.

scholarly journals Extracellular matrix of lymphoid tissues in the chick.

1989 ◽  
Vol 37 (5) ◽  
pp. 757-763 ◽  
Author(s):  
A Colombatti ◽  
A Poletti ◽  
A Carbone ◽  
D Volpin ◽  
G M Bressan
Keyword(s):  
Extracellular Matrix ◽  
Epithelial Cells ◽  
Basement Membrane ◽  
Basement Membranes ◽  
Intestinal Lumen ◽  
Lymphoid Tissues ◽  
White Pulp ◽  
Extracellular Matrix Components ◽  
Coarse Fibers ◽  
Distribution Of Components

We describe the immunohistochemical distribution of components of the extracellular matrix of the chick lymphoid system. In the thymus, basement membranes of epithelial cells bordering the lobules were intensely stained by laminin antibodies; fibronectin antibodies labeled the capsule and the septal matrix, and similar reactivity was seen with tropoelastin and gp 115 antibodies. No positivity was detected with any of the antibodies within the cortical parenchymal cells. Laminin was not detected in the medullary parenchyma, whereas fibronectin was present as coarse fibers. Tropoelastin and gp 115 appeared as a finer and more diffuse meshwork. In the bursa, laminin antibodies outlined the epithelial cells separating the cortex from the medulla. Fibronectin, tropoelastin, and gp 115 antibody stained the interfollicular septa and the cortical matrix, although to a different extent. Laminin was also detected in association with the interfollicular epithelium (IFE) basement membrane, whereas no staining was found underneath the follicle-associated epithelium (FAE). FAE cells not only lack a proper basement membrane but are also not separated from medullary lymphocytes by any of the other extracellular matrix components were investigated. Consequently, medullary lymphocytes are not sequestered, and can come easily into contact with antigens present in the intestinal lumen. All four antibodies stained the spleen capsule and spleen blood vessels, tropoelastin and gp 115 antibodies giving the strongest reactivity. A fine trabecular staining pattern was detected with gp 115 antibodies in the white pulp.

Laminin α-chain expression and basement membrane formation by MLE-15 respiratory epithelial cells

2002 ◽  
Vol 282 (5) ◽  
pp. L1004-L1011 ◽  
Author(s):  
Nguyet M. Nguyen ◽  
Yushi Bai ◽  
Katsumi Mochitate ◽  
Robert M. Senior
Keyword(s):  
Epithelial Cells ◽  
Basement Membrane ◽  
Critical Role ◽  
Basement Membranes ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
Respiratory Epithelial Cells ◽  
Alveolar Type Ii Cells ◽  
Respiratory Epithelial

Basement membranes have a critical role in alveolar structure and function. Alveolar type II cells make basement membrane constituents, including laminin, but relatively little is known about the production of basement membrane proteins by murine alveolar type II cells and a convenient system is not available to study basement membrane production by murine alveolar type II cells. To facilitate study of basement membrane production, with particular focus on laminin chains, we examined transformed murine distal respiratory epithelial cells (MLE-15), which have many structural and biochemical features of alveolar type II cells. We found that MLE-15 cells produce laminin-α5, a trace amount of laminin-α3, laminins-β1 and -γ1, type IV collagen, and perlecan. Transforming growth factor-β1 significantly induces expression of laminin-α1. When grown on a fibroblast-embedded collagen gel, MLE-15 cells assemble a basement membrane-like layer containing laminin-α5. These findings indicate that MLE-15 cells will be useful in modeling basement membrane production and assembly by alveolar type II cells.

scholarly journals Expression of extracellular matrix components is regulated by substratum.

1990 ◽  
Vol 110 (4) ◽  
pp. 1405-1415 ◽  
Author(s):  
C H Streuli ◽  
M J Bissell
Keyword(s):  
Extracellular Matrix ◽  
Epithelial Cells ◽  
Basement Membrane ◽  
Type I Collagen ◽  
Basement Membranes ◽  
Type I ◽  
Collagen Gels ◽  
Extracellular Matrix Components ◽  
Matrix Components ◽  
Cells Cultured

Reconstituted basement membranes and extracellular matrices have been demonstrated to affect, positively and dramatically, the production of milk proteins in cultured mammary epithelial cells. Here we show that both the expression and the deposition of extracellular matrix components themselves are regulated by substratum. The steady-state levels of the laminin, type IV collagen, and fibronectin mRNAs in mammary epithelial cells cultured on plastic dishes and on type I collagen gels have been examined, as has the ability of these cells to synthesize, secrete, and deposit laminin and other, extracellular matrix proteins. We demonstrate de novo synthesis of a basement membrane by cells cultured on type I collagen gels which have been floated into the medium. Expression of the mRNA and proteins of basement membranes, however, are quite low in these cultures. In contrast, the levels of laminin, type IV collagen, and fibronectin mRNAs are highest in cells cultured on plastic surfaces, where no basement membrane is deposited. It is suggested that the interaction between epithelial cells and both basement membrane and stromally derived matrices exerts a negative influence on the expression of mRNA for extracellular matrix components. In addition, we show that the capacity for lactational differentiation correlates with conditions that favor the deposition of a continuous basement membrane, and argue that the interaction between specialized epithelial cells and stroma enables them to create their own microenvironment for accurate signal transduction and phenotypic function.

Ultrastructure of the Celis of a Fish Tastebud

1976 ◽  
Vol 34 ◽  
pp. 128-129
Author(s):  
Gary E. Korte
Keyword(s):  
T Cells ◽  
Epithelial Cells ◽  
Basement Membrane ◽  
B Cell ◽  
Cell Types ◽  
Afferent Nerve ◽  
The Other ◽  
Nerve Plexus ◽  
The Subject ◽  
First Time

Four types of specialized epithelial cells have been observed in the fish tastebud, within the capsule formed by the flattened epidermal cells. However, only two or three of these have been previously noted in any one species, including the glass catfish Kryptopterus bicirrhis, the subject of this investigation (1,2). For the first time, all four types of specialized cells have been observed,and an artifact of fixation relevant to the identification of these cell types has been uncovered.A single basal, or B cell lies on the basement membrane of the epidermis (Fig. 1). It makes many synapses with the afferent nerve plexus, which lies just above it. The other three cell types, designated S,L and T cells (Fig. 2A) are external to the nerve plexus, and only rarely make synapses onto nerves, confirming the observations of several other investigations.

scholarly journals Comparison of the ability of basement membranes produced by corneal endothelial and mouse-derived Endodermal PF-HR-9 cells to support the proliferation and differentiation of bovine kidney tubule epithelial cells in vitro.

1984 ◽  
Vol 99 (3) ◽  
pp. 947-961 ◽  
Author(s):  
D Gospodarowicz ◽  
J Lepine ◽  
S Massoglia ◽  
I Wood
Keyword(s):  
Epithelial Cells ◽  
Basement Membrane ◽  
Cell Monolayer ◽  
Basement Membranes ◽  
Low Density ◽  
Kidney Tubule ◽  
Confluent Monolayer ◽  
Bovine Kidney ◽  
Fibroblastic Cells

The proliferation and morphological differentiation of bovine kidney collecting-tubule epithelial cells has been examined as a function of substrata and plasma factors. Collecting kidney tubule explant maintained in vitro gave rise to two distinct cell populations; one was composed mostly of fibroblastic cells whereas the other was epithelioid (EP cells). The proliferation of fibroblastic cells when exposed to serum-supplemented medium was best expressed when cells were maintained on a basement membrane produced by bovine corneal endothelial cells. This basement membrane has a composition, which in previous studies has been shown to favor the proliferation of mesenchymal cells. In contrast, the proliferation of EP cells was best expressed when cells were maintained on a basement membrane produced by the mouse-derived endodermal cell line PF-HR-9 (HR-9-BM). This basement membrane has a biochemical composition very similar to the basement membrane underlying the kidney tubules. Although the fibroblast confluent monolayer maintained on bovine corneal endothelial cell extracellular matrix did not undergo morphogenesis, the confluent monolayer of EP cells maintained on HR-9-BM shows hemicyst formation, suggesting that they were capable of vectorial fluid transport. They also built a complex three-dimensional kidney tubulelike network. Some tubules became grossly visible and floated into the tissue culture medium, remaining tethered to the cell monolayer at either end of the tubule. On an ultrastructural level, the tubules consisted of cells held together with junctional complexes arranged so as to form a lumen. The smallest lumen were bordered by 2-3 cells, and the largest ones by 8-15 cells. The lumens of the larger tubules did contain granular fibrillar and amorphous debris. Low-density EP cell cultures maintained on HR-9-BM could be induced to proliferate at a rate approaching that of cultures exposed to serum when they were exposed to medium supplemented with high-density lipoprotein (HDL, 750 micrograms protein/ml) and transferrin (50 micrograms/ml). When exposed to HDL concentrations equal or lower than 250 micrograms protein/ml, low-density cultures proliferated at a slow rate and readily formed tubulelike structures. This observation indicates that EP cells do not need to reach confluence to undergo morphogenesis, and that HDL, which in the presence of transferrin supports the cell proliferation, can favor their differentiation into tubulelike structures once its concentration becomes limiting for mitogenesis.

scholarly journals TRANSPORT OF GLOBIN BY THE RENAL GLOMERULUS

1964 ◽  
Vol 120 (6) ◽  
pp. 1129-1138 ◽  
Author(s):  
Max G. Menefee ◽  
C. Barber Mueller ◽  
Allen L. Bell ◽  
Joseph K. Myers
Keyword(s):  
Endothelial Cells ◽  
Electron Microscope ◽  
Basement Membrane ◽  
Basement Membranes ◽  
Renal Glomerulus ◽  
Thin Sections ◽  
Characteristic Appearance ◽  
Pass Through ◽  
Surrounding Membrane ◽  
Glomerular Capillaries

Purified human globin injected into rats forms aggregates which are identifiable by their characteristic appearance in thin sections in the electron microscope and by their positive autoradiographs when the globin is tritiated before injection. Globin is taken up by endothelial cells of glomerular capillaries and is transported across the cell within the limits of a surrounding membrane. Globin is rarely seen to pass through fenestrations. Globin is also taken into the stalk region where it is seen usually within the sponge fibers and only occasionally within stalk cells. Globin is seen in all stages of passage through the basement membranes and sponge fibers, which are not deformed by its passage. On the basis of the findings presented here and by others, it is postulated that the basement membrane and sponge fibers consist of a thixotrophic gel. After traversing the basement membrane, the globin passes between foot processes of the epithelial cells. The slit membranes are deformed by this passage and thus appear to be distinctive structures. The globin is next found free in Bowman's space; the earliest aggregates are seen there within 1 minute after injection. Globin taken up in the stalk region is slowly discharged and very little is found there 6 hours postinjection.

scholarly journals THE HISTOGENESIS OF BASEMENT MEMBRANES

1963 ◽  
Vol 117 (3) ◽  
pp. 339-348 ◽  
Author(s):  
G. B. Pierce ◽  
A. R. Midgley ◽  
J. Sri Ram
Keyword(s):  
Epithelial Cells ◽  
Connective Tissue ◽  
Basement Membrane ◽  
Yolk Sac ◽  
Basement Membranes ◽  
Ground Substance ◽  
Epithelial Secretion ◽  
Reichert's Membrane ◽  
Yolk Sac Cells

A parietal yolk sac carcinoma of the mouse that secretes large quantities of basement membrane-like material has been used to study the formation of basement membranes. Suitably characterized fluorescein-labeled antibodies against this material stained basement membranes of epithelial structures and vessels, as well as reticulin. When absorbed with reticulin and vascular basement membranes of the spleen until these structures no longer fluoresced, the antibody still stained the basement membrane-like material of the tumor, its normal embryonic counterpart (Reichert's membrane), and the basement membranes at the bases of epithelial cells. The observation made previously that parietal yolk sac cells secreted, in the absence of connective tissue and reticulin, the basement membrane (Reichert's membrane) upon which they rested has been confirmed through the localization of ferritin-labeled antibody to the endoplasmic reticulin of the secreting cells. Since a basement membrane proven to be an epithelial secretion is antigenically similar to basement membranes at the bases of all epithelial cells studied but antigenically different from connective tissue elements, it is postulated that the basement membranes at the bases of epithelial cells in general are an epithelial secretion, and are not a condensation of ground substance as is commonly believed.

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