Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The polycation hexadimethrine (HDM) binds to anionic sites in the glomerular basement membrane (GBM) and causes heavy proteinuria when infused in vivo. An in vitro assay of 3H-HDM binding to isolated dog GBM was developed, to permit further analysis of the GBM components binding HDM. 3H-HDM binding to isolated GBM was saturable, reversible in dose-dependent fashion by competing polycations, and inhibited by increasing salt concentration and low pH. The pH dependence of binding suggested that most of the HDM binds to carboxyl groups rather than to the sulfate groups of proteoglycans. Removal of heparan sulfate by heparinase or purified heparatinase had no detectable effect on HDM binding. Treatment of GBM with neuraminidase, hyaluronidase, or chondroitinase reduced binding of HDM by a maximum of 20 to 38%. However, substitution of carboxyl anions with nonionizable glycine methyl ester residues resulted in complete elimination of HDM binding. Parallel results were obtained in studies of glomerular localization of cationized ferritin (CatF), pI 8.5. After carboxyl substitution, GBM did not bind CatF; heparinase-treated GBM bound CatF in a distribution not demonstrably different from normal. Cellulose acetate electrophoresis of glycosaminoglycan fractions prepared from treated GBM confirmed that carboxyl modification did not alter the content or charge of the heparan sulfate of GBM, but heparinase treatment removed at least 90% of heparan sulfate. The results indicate that carboxyl groups are quantitatively more important than heparan sulfate for binding of HDM in vitro. Since HDM causes proteinuria in vivo, carboxyl groups may be important for maintenance of normal permselectivity.
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PMID:Polycation binding to glomerular basement membrane. Effect of biochemical modification. 380 16

Extraction of rat glomerular basement membrane, purified by osmotic lysis and sequential detergent treatment, with 8 M urea containing protease inhibitors solubilizes protein that is devoid of hydroxyproline and hydroxylysine. This material represents 8-12% of total membrane protein, elutes mainly as two high molecular weight peaks on agarose gel filtration, and is associated with glycosaminoglycans. Isolated rat renal glomeruli incorporate [35S]sulfate into basement membrane from which this non-collagenous 35S-labeled fraction can be subsequently solubilized. The radioactivity incorporated into urea-soluble glomerular basement membrane eluted primarily with the higher molecular weight peak (Mr greater than 250 000). Cellulose acetate electrophoresis after pronase digestion of the urea-soluble fraction revealed glycosaminoglycan that was resistant to digestion with Streptomyces hyaluronidase and chondroitinase ABC, sensitive to nitrous acid treatment, and contained [35S]sulfate. The findings indicate that one of the non-collagenous components of glomerular basement membrane is a proteoglycan containing heparan sulfate.
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PMID:Non-collagen protein and proteoglycan in renal glomerular basement membrane. 731 55

The synthesis of sulphated glycosaminoglycans (GAG) and hyaluronan (HA) was studied in 3 cell strains incubated at 37 degrees C or 42 degrees C. Cells were labelled with [3H]glucosamine and [35S]sulphate. No incorporation of [35S]sulphate was observed at 42 degrees C. Cellulose acetate electrophoresis of GAGs synthesized at 42 degrees C showed only one [3H]glucosamine-labelled band completely digested with Streptomyces hyaluronidase. The quantification of [3H]glucosamine-labelled GAGs before and after hyaluronidase treatment indicated an increased rate of HA synthesis at 42 degrees C as compared to the rate of synthesis at 37 degrees C. These results suggest that hyperthermia stimulates HA synthesis and inhibits sulphated GAG synthesis in several cell strains which in turn may contribute to the modification of extracellular environment in inflammation.
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PMID:Effect of hyperthermia on the extracellular matrix. I. Heat enhances hyaluronan and inhibits sulphated glycosaminoglycan synthesis. 822 13