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)

When normal or SV40-transformed Balb/c 3T3 cells are treated with the Ca++-specific chelator EGTA, they round up and pull away from their footpad adhesion sites to the serum-coated tissue culture substrate, as shown by scanning electron microscope studies. Elastic membranous retraction fibers break upon culture agitation, leaving adhesion sites as substrate-attached material (SAM) (Cells leave "footprints" of substrate adhesion sites during movement by a very similar process.) SAM contains 1-2% of the cell's total protein and phospholipid content and 5-10% of its glucosamine-radiolabeled polysaccharide, most of which is glycosaminoglycan (GAG). By one- and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis, there is considerable enrichment in SAM for specific GAGs; for the glycoprotein fibronectin; and for the cytoskeletal proteins actin, myosin, and the subunit protein of the 10 nm-diameter filaments. Fibrillar fibronectin of cellular origin and substratum-bound fibronectin of serum origin (cold-insoluble globulin, CIg) have been visualized by immunofluorescence microscopy. The GAG composition in SAM has been examined under different cellular growth and attachment conditions. Heparan sulfate content correlates with glycopeptide content (derived from glycoprotein). Newly attaching cells deposit SAM with principally heparan sulfate and fibronectin and little of the other GAGs. Hyaluronate and chrondroitin proteoglycans are coordinately deposited in SAM as cells begin spreading and movement over the substrate. Cells attaching to serum-coated or CIg-coated substrates deposited SAM with identical compositions. The proteoglycan nature of the GAGs in SAM has been examined, as well as the ability of proteoglycans to form two classes of reversibly dissociable "supramolecular complexes" - one class with heparan sulfate and glycopeptide-containing material and the second with hyaluronate-chondroitin complexes. Enzymatic digestion of "intact" SAM with trypsin or testicular hyaluronidase indicates that (1) only a small portion of long-term radiolabeled fibronectin and cyto-skeletal protein is bound to the substrate via hyaluronate or chondroitin classes of GAG; (2) most of the fibronectin, cytoskeletal protein and heparan sulfate coordinately resist solubilization; and (3) newly synthesized fibronectin, which is metabolically labile in SAM, is linked to SAM by hyaluronate- and/or chondroitin-dependent binding. All of our studies indicate that heparan sulfate is a direct mediator of adhesion of cells to the substrate, possibly by binding to both cell-surface fibronectin and substrate-bound CIg in the serum coating; hyaluronate-chondroitin complexes in SAM appear to be most important in motility of cells by binding and labilizing fibronectin at the periphery of footpad adhesions, with subsequent cytoskeletal disorganization.
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PMID:Fibronectin and proteoglycans as determinants of cell-substratum adhesion. 23 21

An enzymic method is described which allows the isolation under comparable conditions of crypt and villus cells from rat jejunum with normal morphologic appearance and high metabolic activity when compared with previous preparations. The method is based on a differential scraping of short lengths of everted small intestine to yield two villus cell fractions and a gut wall residue. The scrapings and the gut tube are incubated for the same length of time in a HEPES-buffered modified Hanks' balanced salt solution containing hyaluronidase, DNase, and soybean trypsin inhibitor. The cells of the crypt region are recovered by a further scraping of the digested gut wall. Cells from all fractions are dispersed by gentle agitation, washed, and harvested by centrifugation. The final crypt and villus cells are 95--99% viable by dye exclusion and exhibit 5--20% cross-contamination on the basis of differential marker enzymes. The isolated crypt and villus cells prepared by the new procedure are suitable for comparative studies of metabolic activity in the absence of chelation-induced structural and metabolic abnormalities.
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PMID:Improved isolation of villus and crypt cells from rat small intestinal mucosa. 49 96

To conduct SEM studies on epithelium containing mucus-producing cells it is essential to remove the mucus which normally obscures the epithelial surface. This study presents a method which effectively removes the covering layer of mucus in the rat middle ear. Healthy Sprague-Dawley rats were decapitated and the middle ears dissected free. Incubation and agitation of the middle ear specimens in hyaluronidase (50 IE ml-1) and/or glucosidase (8%) removed the mucus from the middle ear cavity without altering the surface structures. It was also revealed that substances such as polyvinyl-pyrrolidone (PVP) (used to increase the colloid osmotic pressure of, e.g., the fixative solution) must be omitted when preparing ciliated specimens for SEM.
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PMID:The use of hyaluronidase and glucosidase to remove mucus from the rat middle ear cavities for SEM studies. 158 77

A method for the isolation and culture of intact intrahepatic bile ducts from normal rats, and its use in studying putative inducers of biliary epithelial cell (BEC) hyperplasia was developed. Ducts were isolated by sequential perfusion of the liver with EGTA and collagenase-hyaluronidase followed by mild mechanical agitation. The resultant fraction, consisting of numerous small bile ducts within a connective tissue framework, was collected and embedded in a collagen gel and cultured on a raft assembly in Medium 199 supplemented with 15% newborn calf serum and antibiotics. Following 10-15 days in culture, the tissue consisted of dilated bile ducts lined by large cuboidal to elongated BEC. At day 15, the BEC 3H-thymidine-labelling index was 5.56 +/- 0.66% (mean +/- s.e.m.) which is nine times that observed in normal rat BEC in situ and similar to the rate of cell division of BEC lining hyperplastic ductules following bile duct ligation in the rat. Putative cholangiotrophic factors, proline, lithocholic acid and extracts of liver and small intestinal mucosa from normal rats and rats after 3 weeks' total biliary obstruction (TBO), were added to the culture medium for the last 5 days of a 15-day culture. With the exception of the extract of liver following TBO which had a growth inhibitory effect and lithocholic acid which was toxic, these treatments did not result in any alteration in the rate of BEC replication.
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PMID:Isolation and culture of intrahepatic bile ducts and its application in assessing putative inducers of biliary epithelial cell hyperplasia. 330 83

1. Two polysaccharides were isolated from the interstitial matrix surrounding the photoreceptor cells of cattle retina. They were liberated from this region of the tissue in a soluble form after agitation of whole retinas in 0.9% sodium chloride. One, which comprises two-thirds of the polysaccharides present, is a hyaluronidase-sensitive ;half-sulphated' chondroitin sulphate containing uronic acid, galactosamine and sulphate in the molar proportions 1.27:1.0:0.54. The other is a hyaluronidase-resistant non-sulphated heteropolysaccharide for which the name sialoglycan is proposed. It contains galactose, glucosamine and sialic acid in the molar proportions 2.4:1.0:0.4. Both polysaccharides contain only small amounts of nitrogen in excess of the amount calculated from their amino sugar and sialic acid content. 2. A similar combination of mucopolysaccharides is associated with the pigment epithelial-cell layer but in quantities only one-fifth of those present in the adjacent matrix area. 3. The ease with which they are released into aqueous media is consistent with the assumption that they are present in the extracellular spaces in both of these tissue layers. 4. The retinal residue left after removal of the two soluble polysaccharides is rich in amino sugar- and sialic acid-containing polymers, which appear to be firmly bound to the tissue fragments. 5. About one-third of the sialic acid and one-tenth of the amino sugar could be extracted with chloroform-methanol. The components in this fraction were tentatively identified as gangliosides. 6. Digestion of the chloroform-methanol-insoluble residue with Pronase yielded as the principal product a heteropolysaccharide containing 16.5% of glucosamine, 24.3% of neutral sugar (galactose plus fucose) and 18.1% of sialic acid. This substance has been classified as a sialoglycan of composition similar to (but not identical with) that of the soluble one isolated from the matrix area of the tissue.
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PMID:The acid mucopolysaccharides of cattle retina. 423 42

A procedure for the isolation of myocytes from adult rat hearts is described. It is based on successive treatments with Ca2+-free medium, disaggregating enzymes (collagenase and hyaluronidase) and mechanical agitation. Several recent isolation methods were compared and their best features were combined, together with some original modifications. A good yield of high purity myocytes with excellent morphological and functional integrity was obtained. The cells are tolerant to physiological concentrations of Ca2+. Cellular levels of ATP, Na+, and K+ are close to those in intact hearts and glucose oxidation rates and succinate exclusion are also close to normal. These characteristics are maintained for periods over 1 h.
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PMID:Isolation of Ca2+-tolerant myocytes from adult rat heart. 642 25

We have used the enzyme elastase to remove the basal lamina of epithelia from two insects: the upper Malpighian tubules of Rhodnius prolixus and imaginal discs of Drosophila melanogaster. Removal of the basal lamina was confirmed using scanning and transmission electron microscopy. Use of the technique on the Malphighian tubules of Rhodnius reveals for the first time the three-dimensional organization of the circumferential folds of the basal plasma membrane. Elastase is much more effective in removing the basal lamina than are the enzymes hyaluronidase, collagenase, and chymotrypsin, either alone or in combination. Following elastase treatment, cells of the Malpighian tubules dissociate with only mild mechanical agitation into single, viable cells. Treatment with elastase removes the basal laminae of imaginal discs of Drosophila and accelerates evagination as has been previously described for trypsin. To obtain single cell preparations from elastase-treated imaginal discs, mechanical stirring in Ringer low in Ca2+ was required. In addition to its usefulness in cell isolation, elastase treatment allows examination of the effect of removal of basal laminae on the physiology and development of insect epithelia.
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PMID:Removal of insect basal laminae using elastase. 643 33

Four media are used to isolate enterocytes from the jejunum of the mouse (basic medium with either hyaluronidase, dispase, pronase, or EDTA). During incubation the intestinal wall is gently agitated. Layers of epithelial cells rather than single cells are removed from the mucosal surface by these procedures. Small groups of enterocytes and single cells can be obtained by further mechanical agitation, e.g. by repeatedly washing the isolated epithelia. Similar morphological findings (transmission and scanning electron microscopy) are obtained after using the various isolation media. Only with EDTA a dilatation of the endoplasmic reticulum is regularly seen. Isolation of the enterocytes starts from the tip of the intestinal villus. The straight apical surface becomes convex and the most lateral microvilli of the brush border desintegrate. The opening of the terminal bars can be observed. Surface differentiations on the lateral cell surfaces of isolated enterocytes become less obvious and disappear. This is discussed with respect to the so-called "lateral vacuoles" which appear in isolated enterocytes. Large spherical protrusions are developed at the basal surface of enterocytes. The cell membrane covering these protrusions is frequently found to be discontinuous. No other cell organelles than ribosomes are to be seen inside of these protrusions. Membrane-bound vesicles are also frequently seen. It is suggested that the basal spherical protrusions are casted off.
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PMID:[Grid electron microscopy studies of isolated intestinal epithelium]. 679 8

A boy presented at age 3.5 months with joint contractures, restlessness, and pain on handling. His skin was thickened and there were livid-red macular lesions over bony prominences. Infantile systemic hyalinosis (ISH) was diagnosed, a presumably autosomal recessive, progressive, and painful disorder of as yet unknown pathogenesis. Observation over three years confirmed the diagnosis as typical changes, such as nodules on both ears, pearly papules in the perinasal folds and on the neck, fleshy nodules in the perianal region, and gingival hypertrophy, developed. Skin lesions and painful joint contractures progressed in spite of intense physiotherapy, and at age 3, the child had marked motor disability. The central nervous system (CNS) appeared to be intact and the infant showed normal mental development. Radiologic findings included marked generalized osteopenia, osteolytic erosions in the metaphyses of the long bones, and cortical thinning. Electron microscopy of two skin biopsies demonstrated deposition of floccular amorphous substance that was abundant around, and appeared to originate from, small blood vessels in the dermis, partially interfering with collagen fiber formation. Lysosomal inclusions were not seen. Serum acid hyaluronidase activity was within the normal range, and the synthesis of hyaluronic acid and proteoglycans in cultured skin fibroblasts was similar to that of control cells. A younger sister presented at age two months with painful joint contractures and discrete livid-red macules over both malleoli, and showed a similar progression of the disorder over the first year of life. The diagnosis of ISH should be considered in infants and children presenting with painful joint contractures and skin lesions. The pathogenesis of this disabling and disfiguring disorder remains unclear. Our data confirm probable autosomal recessive inheritance, and do not support lysosomal storage, hyaluronidase deficiency, or a primary collagen disorder, but indicate that the amorphous material accumulating in the skin and articular soft tissues may originate from the blood circulation.
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PMID:Infantile systemic hyalinosis in siblings: clinical report, biochemical and ultrastructural findings, and review of the literature. 1129 73