Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aminonucleoside of puromycin induces proteinuria and renal damage when given to rats. Aminonucleoside of puromycin was administered to male Wistar-Furth rats as a single intravenous injection in a dose of 15 mg. per 100 gm. of body weight. The animals were studied 9 days later when the mean urinary protein was 175 mg. per 24 hours. Evidence of glomerular epithelial cell injury included massive obliteration of foot processes, appearance of microvilli, protein reabsorption droplets, extreme attenuation of cytoplasm with formation of blebs, and focal detachment of epithelial cells from glomerular basement membrane. An increase in both the amount of mesangial matrix and the number of mesangial cells was also observed. The fractional clearance (C/GFR) of anionic horseradish peroxidase had increased 18.5 times as compared to control values and was nearly equal to the C/GFR of neutral horseradish peroxidase in the experimental rats. The C/GFR of cationic horseradish peroxidase was decreased by one-third so that it approximated the C/GFRs of both anionic and neutral horseradish peroxidase. These findings indicate a nearly complete loss of the charge-selective barrier to filtration. In addition, C/GFRs of tritiated uncharged dextrans with a range of molecular radii from 18 to 58 Angstrom (A) were determined. The C/GFRs of dextrans (alpha e less than 30 A) were decreased in the experimental rats as compared to C/GFRs of dextrans of corresponding molecular size in control rats. However, the C/GFRs of dextrans (alpha e greater than 38A) were increased in experimental as compared to control rats. Further, both anionic and cationic ferritin (alpha e = 61 A) were observed in the urinary space near denuded areas of glomerular basement membrane. These results indicate that the size-selective properties of the glomerular barrier to filtration have been modified with decreased C/GFR of small molecules and increased C/GFR of large molecules. Thus, the proteinuria of aminonucleoside nephrosis in rats occurs secondary to alterations in both the charge- and size-selective barriers to glomerular filtration.
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PMID:Alterations in the charge and size selectivity barrier of the glomerular filter in aminonucleoside nephrosis in rats. 746 51

To clarify the roles of the glomerular basement membrane (GBM) in filtration mechanisms, human liver ferritin was used for the first time as a tracer. Urinary excretion of human liver ferritin was measured and the injected ferritin was tracked under electron microscopy. Puromycin aminonucleoside (PAN) nephrosis was induced in Sprague Dawley rats and normal saline was injected into control rats. Monomeric and polymeric human ferritin were isolated from post mortem samples. Both kinds of human liver ferritin were injected into the experimental and control rats and urine samples were examined for human ferritin by radioimmunoassay. Rats with PAN nephrosis excreted approximately 33 times more monomeric ferritin than the controls. Appreciably more monomeric ferritin was excreted than polymeric ferritin. In control rats, monomeric ferritin particles were restricted in the lamina rara interna and inner aspect of the glomerular basement membrane 30 min after injection. On the other hand, in rats with PAN nephrosis, monomeric ferritin particles were seen throughout the width of the GBM and in the epithelial cells. With human liver ferritin, we were able to demonstrate the escape of the ferritin into the urine in addition to conducting the conventional electron microscopic tracer study of the glomerular capillary wall. Human liver ferritin shows potential as a useful tracer in the study of glomerular permselectivity.
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PMID:Studies on the glomerular permeability with human liver ferritin. 813 33