scholarly journals Effects of experimental nephrosis on basement-membrane components and enzymes of collagen biosynthesis in rat kidney

1985 ◽  
Vol 226 (1) ◽  
pp. 243-250 ◽  
Author(s):  
A Jukkola ◽  
J Risteli ◽  
H Autio-Harmainen ◽  
L Risteli
Keyword(s):  
Membrane Proteins ◽  
Basement Membrane ◽  
Indirect Immunofluorescence ◽  
Type Iv Collagen ◽  
Rat Kidney ◽  
Kidney Tissue ◽  
Kidney Cortex ◽  
Collagen Biosynthesis ◽  
Type Iv ◽  
Basement Membrane Proteins

The aim of the present study was to find out whether the basement-membrane proteins laminin and type IV collagen are involved in the development of aminonucleoside-induced nephrosis. These proteins were measured by specific radioimmunoassays in serum, urine and kidney-cortex samples, and they were localized in the glomeruli by indirect immunofluorescence. Nephrosis was induced in rats with a single intraperitoneal injection of puromycin aminonucleoside. Serum laminin concentrations, detected by a radioimmunoassay for the P2 domain of the protein, increased to reach a maximum at days 5-7, and they remained elevated until at least day 14. The increase preceded the development of proteinuria, suggesting a role for laminin in glomerular function. Concomitant with proteinuria, increasing amounts of laminin antigenicity were also found in the urine. The size of the laminin antigen in serum was estimated by gel filtration, and the serum forms were found to contain both the P1 and the P2 regions of the intact laminin molecule. On the other hand, there were no changes in the serum or urinary concentrations of type-IV-collagen-derived antigens, as detected by a radioimmunoassay for the 7S collagen domain of this protein. The total content of laminin in kidney cortex, measured after digestion of the tissue with trypsin and collagenase, was, at day 9, still comparable with normal values, and the distribution of both basement-membrane proteins in the glomeruli, studied by indirect immunofluorescence, was similar to that in the controls. The tissue damage induced by aminonucleoside, however, seems to stimulate collagen biosynthesis, as the activities of prolyl 4-hydroxylase, lysyl hydroxylase and galactosylhydroxylysyl glucosyltransferase in kidney tissue increased significantly, with maxima at days 8-10.

Platelet Interaction With Basement Membrane Proteins

1981 ◽  
Author(s):  
L Balleisen ◽  
J Rauterberg ◽  
J Risteli ◽  
H Rohde ◽  
R Timpl
Keyword(s):  
Membrane Proteins ◽  
Basement Membrane ◽  
Type Iv Collagen ◽  
Fibrin Clot ◽  
Basement Membranes ◽  
Plastic Substrate ◽  
Acid Extraction ◽  
Clot Retraction ◽  
Type Iv ◽  
Basement Membrane Proteins

Basement membranes consist mainly of two components: non-fibrillar type IV collagen and the non-collagenous glycoprotein laminin (m.w.900.000) which is capable to interact with cell surfaces. The collagenous protein was studied in form of two major fragments comprising together the total mass of the molecule. 7-S collagen which resembles the crosslinking domain of type IV collagen was isolated after collagenase digestion and consisted of four triple helices aligned in a parallel fasion (m.w.360.000). The major triple helical domain of type IV collagen (m.w.450.000) could be obtained by a acid extraction but had lost most of the 7-S domain.Interaction with platelets was examined in aggregation, cell spreading and fibrin clot retraction assays including the determination of malondialdehyde formation. 7-S collagen was the most active component in all three assays. Aggregation was induced by as little as 25 µg/ml and was confirmed by electronmicroscopy. When compared to interstitial collagens, however, 10-20 fold higher amounts of 7-S collagen are required to produce the same effects. Acid extracted type IV collagen possessed virtually no activity. Laminin did not aggregate platelets but promoted strongly their attachment and spreading on a plastic substrate. Thus both basement membrane proteins apparently interact with platelets in different ways via distinct domains of the molecules.

The basement membrane proteins laminin and type IV collagen in isolated villi in pre-eclampsia

Placenta ◽  
1984 ◽  
Vol 5 (6) ◽  
pp. 541-550 ◽  
Author(s):  
J. Risteli ◽  
J.M. Foidart ◽  
L. Risteli ◽  
J. Boniver ◽  
G. Goffinet
Keyword(s):  
Membrane Proteins ◽  
Basement Membrane ◽  
Type Iv Collagen ◽  
Type Iv ◽  
Basement Membrane Proteins

scholarly journals Comparative distribution of laminin, type IV collagen, and fibronectin in the rat glomerulus.

1982 ◽  
Vol 30 (9) ◽  
pp. 874-886 ◽  
Author(s):  
P J Courtoy ◽  
R Timpl ◽  
M G Farquhar
Keyword(s):  
Type Iv Collagen ◽  
Rat Kidney ◽  
Basement Membranes ◽  
Kidney Cortex ◽  
Mesangial Matrix ◽  
Lamina Densa ◽  
Rat Kidney Cortex ◽  
Type Iv ◽  
Attachment Proteins ◽  
Cryostat Sections

The distribution of laminin, type IV collagen, and fibronectin was investigated in the rat kidney cortex by immunolabeling. It was demonstrated by immunofluorescence on both unfixed cryostat sections and fixed ultracryomicrotome sections, by immunoperoxidase on fixed cryostat sections, and by immunoferritin on isolated glomerular basement membranes (GBM). This multifaceted approach provided complementary and convergent results. Distinct patterns were found for each antigen in the glomerulus and remaining kidney cortex. Laminin was localized predominantly in the GBM, where it was concentrated in the laminae rarae. Staining also occurred to a lesser extent in the mesangial matrix. Type IV collagen was evenly distributed in the lamina densa of the GBM and in the mesangial matrix. Fibronectin was most abundant in the mesangial matrix, but it could also be detected in the peripheral GBM, where it was localized in the laminae rarae. Labeling for fibronectin was particularly prominent at the endothelial-mesangial interface. The findings indicate that the three layers of the GBM differ in their composition: The lamina densa contains type IV collagen and the laminae rarae contain the two attachment proteins, fibronectin and laminin. The mesangial matrix stains for all three antigens, but it is also heterogeneous and can be subdivided into several domains--i.e., the endothelial-mesangial matrix, which is particularly rich in fibronectin, the intermesangial matrix, which contains mainly type IV collagen and fibronectin, and the GBM (where it continues over the mesangial regions), which stains most heavily for laminin.

scholarly journals Localization of Type IV Collagen Alpha Chains in the Basement Membrane of Ameloblastoma, Tooth Germ and Oral Mucosa by Using Indirect Immunofluorescence.

2005 ◽  
Vol 14 (2) ◽  
pp. 235-236
Author(s):  
Hirokuni Kou ◽  
Silvia Susana Borkosky ◽  
Hitoshi Nagatsuka ◽  
Ryo Tamamura ◽  
Keisuke Nakano ◽  
...  
Keyword(s):  
Basement Membrane ◽  
Oral Mucosa ◽  
Indirect Immunofluorescence ◽  
Type Iv Collagen ◽  
Tooth Germ ◽  
Type Iv
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