Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Collagenase was identified within naturally occurring rat chronic otitis media by the use of an immunohistochemical technique with peroxidase-antiperoxidase to stain the paraffin. Collagenase was found in fibroblasts, mononuclear cells, and osteoclast cells in the bone-resorbing area. Collagenase was found only in fibroblasts in contact with epithelial basal cells. Macrophages from rat peritoneum were cultured with different concentrations of a lipopolysaccharide. The prostaglandin E2 level reached a maximum during the 12- to 24-hour period in the presence of endotoxin. This prostaglandin E2 was confirmed by immunofluorescent staining. The endotoxin-activated macrophage produced an insignificant amount of collagenase. These findings suggest that activated macrophages may be able to stimulate fibroblast collagenase production through the chemical mediator prostaglandin E2. Also, the interaction between fibroblasts and epidermal cells appears to encourage and enhance the biochemical events resulting in bone resorption in chronic otitis media.
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PMID:Bone resorption factors in chronic otitis media. 608 44

The effect of vasoactive intestinal polypeptide (VIP) on protein secretion from lacrimal gland was investigated by using acini prepared by collagenase digestion of rat exorbital lacrimal glands. Protein secretion was determined by incubating the acini for 0-40 min and analyzing the supernatant for peroxidase, a protein secreted by the rat exorbital lacrimal gland. VIP (10(-10) to 10(-7) M) stimulated secretion in a concentration-dependent manner. A maximum concentration of VIP (10(-8) M) stimulated secretion to the same extent as a maximum concentration of carbachol (10(-5) M). The cholinergic antagonist atropine at a concentration (10(-5) M) that completely abolished carbachol-induced secretion did not alter VIP-stimulated secretion. The secretory effects of maximal concentrations of VIP and carbachol were additive, but decreasing the carbachol concentration potentiated secretion. Unlike carbachol, which had no effect on the acinar cAMP level, VIP increased cAMP content sixfold. Immunohistochemical staining demonstrated VIP-like immunoreactivity in nerve fibers throughout the gland, distributed primarily around acini. We conclude that VIP-like immunoreactive nerves are present in the lacrimal gland and that VIP can stimulate protein secretion but utilizes a pathway separate from, but convergent with, that used by cholinergic agonists.
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PMID:Vasoactive intestinal polypeptide stimulation of protein secretion from rat lacrimal gland acini. 609 81

Satellite cells were visualized in living muscle fibres of the frog. Single fibres or bundles consisting of a few fibres were isolated after treatment with collagenase, and viewed under the light microscope. Subsequent electron microscopy of identified cells confirmed that they were satellite muscle cells. Under the light microscope, satellite cells appear as fusiform cells, tapering into long fine processes usually orientated parallel to the muscle fibre axis. Horseradish peroxidase injected into the muscle fibre was not transferred to the satellite cells.
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PMID:Visualization of satellite cells in living muscle fibres of the frog. 610 23

A simple and rapid procedure is described for the separation of the human leucocyte enzymes alanine aminopeptidase, cathepsin G, collagenase, elastase and myeloperoxidase. The enzymes are prepared from leucocytes, obtained from buffy coat, by repeated extraction with buffer A(1 M salt concentration). The pooled extracts are successively subjected to batch adsorption on concanavalin A-Sepharose, gel filtration on Sephacryl S-300, affinity chromatography on collagen-Sepharose 4-B, batch adsorption on CM-Sephadex C-50 and adsorption chromatography on hydroxyapatite. The yields of the isolated enzymes of a typical preparation are 47% alanine aminopeptidase, 9% cathepsin G, 90% latent and active collagenase, 23% elastase and approximately 100% myeloperoxidase with respect to the pooled extracts. The cathepsin G, collagenase and elastase preparations are essentially free from other proteolytic enzymes and may be used without further purifications.
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PMID:Separation of the human leucocyte enzymes alanine aminopeptidase, cathepsin G, collagenase, elastase and myeloperoxidase. 612 35

The interaction of human blood platelets with collagenase-treated rabbit subendothelium was studied by histochemical ultrastructural methods and by morphometric semi-quantitative analysis. Aortas were deendothelialized and incubated: 1) with a highly purified bacterial collagenase whose specificity was controlled; and 2) with the same collagenase followed by chymotrypsin. For histochemical studies, tannic acid, ruthenium red, and peroxidase-labeled Ricinus communis and concanavalin A were used. Electron microscopy showed that after digestion of fibrillar collagen by collagenase, adherent and aggregated platelets were observed on Ricinus communis-, concanavalin A-, and ruthenium red-positive glycoprotein microfibrils. After successive incubation with collagenase and chymotrypsin, the microfibrils disappeared. No platelets were observed on the remnant amorphous elastin. Morphometric analysis confirmed the interaction of platelets with collagenase-treated subendothelium. In addition, glycoproteins were extracted from collagenase-treated rabbit aortas using 5 M guanidine. Using an in vitro quantitative test, significant platelet adhesion to these glycoproteins was observed. Our results show an interaction between platelets and noncollagenic glycoprotein microfibrils.
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PMID:Histochemical and ultrastructural characterization of subendothelial glycoprotein microfibrils interacting with platelets. 627 53

A combination of biochemistry and morphology was used to demonstrate that more than 95 percent of the isolated rat hepatocytes prepared by collagenase dissociation of rat livers retained the pathway for receptor-mediated endocytosis of asialoglycoproteins (ASGPs). Maximal specific binding of (125)I-asialoorosomucoid ((125)I-ASOR) to dissociated hepatocytes at 5 degrees C (at which temperature no internalization occurred) averaged 100,000-400,000 molecules per cell. Binding, uptake, and degredation of (125)I- ASOR at 37 degrees C occurred at a rate of 1 x 10(6) molecules per cell over 2 h. Light and electron microscopic autoradiography (LM- and EM-ARG) of (125)I-ASOR were used to visualize the surface binding sites at 5 degrees C and the intracellular pathway at 37 degrees C. In the EM-ARG experiments, ARG grains corresponding to (125)I-ASOR were distributed randomly over the cell surface at 5 degrees C but over time at 37 degrees C were concentrated in the lysosome region. Cytochemical detection of an ASOR-horseradish peroxidase conjugate (ASOR-HRP) at the ultrastructural level revealed that at 5 degrees C this specific ASGP tracer was concentrated in pits at the cell surface as well as diffusely distributed along the rest of the plasma membrane. Such a result indicates that redistribution of ASGP surface receptors had occurred. Because the number of surface binding sites of (125)I-ASOR varied among cell preparations, the effect of collagenase on (125)I-ASOR binding was examined. When collagenase-dissociated hepatocytes were re-exposed to collagenase at 37 degrees C, 10-50 percent of control binding was observed. However, by measuring the extent of (125)I-ASOR binding at 5 degrees C in the same cell population before and after collagenase dissociation, little reduction in the number of ASGP surface receptors was found. Therefore, the possibility that the time and temperature of the cell isolations allowed recovery of cell surface receptors following collagenase exposure was tested. Freshly isolated cells, dissociated cells that were re-exposed to collagenase, and perfused livers exposed to collagenase without a Ca(++)-free pre-perfusion, were found to bind 110-240 percent more(125)I-ASOR after 1 h at 37 degrees C that they did at 0 time. This recovery of surface ASGP binding activity occurred in the absence of significant protein synthesis (i.e., basal medium or 1 mM cycloheximide). Suspensions of isolated, unpolarized hepatocytes were placed in monolayer culture for 24 h and confluent cells were demonstrated to reestablish morphologically distinct plasma membrane regions analogous to bile canalicular, lateral, and sinusoidal surfaces in vivo. More than 95 percent of these cells maintained the capacity to bind, internalize, and degrade (125)I-ASOR at levels comparable to those of the freshly isolated population. ASOR-HRP (at 5 degrees C) was specifically bound to all plasma membrane surfaces of repolarized hepatocytes (cultured for 24 h) except those lining bile canalicular-like spaces. Thus, both isolated, unpolarized hepatocytes and cells cultured under conditions that promote morphological reestablishment of polarity maintain the pathway for receptor- mediated endocytosis of ASGPs.
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PMID:Cell surface distribution and intracellular fate of asialoglycoproteins: a morphological and biochemical study of isolated rat hepatocytes and monolayer cultures. 628 90

The observation of the amoebocytes of primitive organisms led ELIAS METSCHNIKOFF in 1882 to the idea that blood phagocytes--neutrophilic leukocytes in particular--could constitute an anti-microbial defense system. This was the beginning of the phagocyte theory which METSCHNIKOFF developed over many years and which in essence is still valid. The author sets out to provide an updated view of the neutrophil. Circulating neutrophils are end-cells. They develop in the bone marrow by a relatively long maturation process during which the characteristic azurophil and specific granules are formed. The granules are stored organelles. The azurophil granules contain microbicidal enzymes, i.e. myeloperoxidase and lysozyme, together with a large number of acid hydrolases and neutral proteases. The specific granules contain lysozyme, a collagenase, lactoferrin and transcobalamines. By subcellular fractionation a third kind of storage organelle has recently been found which is characterized by its gelatinase content. Circulating neutrophils are activated on microbial invasion--first in the blood, by chemotactic factors formed at the site of infection, and subsequently by the microbes themselves which are phagocytosed by the immigrating neutrophils. Chemotactic factors lead to directed migration and induce the secretion of enzymes which presumably facilitate this process. Phagocytosis results in the mobilization of neutrophil products in large quantities. The contact between the cell and the microorganism activates in the neutrophil membrane an oxidase which produces superoxide, and a phospholipase which releases arachidonic acid. The latter is then oxidized by cyclooxygenase and lipoxygenase. There is also massive liberation of enzymes from all three storage compartments. The production of superoxide is the essential process for the killing of a large variety of microorganisms.
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PMID:[Phagocytes and phagocytosis 100 years after Metchnikoff. A current picture of the neutrophil leukocyte]. 629 50

A beta 1-serum component, beta 1-anticollagenase, capable of inhibiting various mammalian tissue collagenases, was isolated from human plasma by gel filtration, affinity chromatography and ion-exchange chromatography. The inhibitor contains 1-2 free sulfhydryl groups, which are a prerequiste for inhibitory activity and for binding to the thiol-Sepharose affinity support. Alkylation of beta 1-anticollagenase by iodoacetamide blocks inhibitory activity. The inhibitor was purified to apparent homogeneity and exhibited a Mr = 30500 determined by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. The amino acid and carbohydrate composition was determined. According to its composition and the isoelectric focussing beta 1-anticollagenase is an acidic protein with an isoelectric point of 5.6. Inhibition of human leukocyte collagenase proceeds in a strong 1 : 1 stoichiometric reaction. The mechanism of this association takes place by a disulfide/thiol interchange reaction as has been previously indicated for human leukocyte collagenases in forming the latent enzyme [Macartney, H. W. and Tschesche, H. (1980) FEBS Lett. 119, 327-332]. The beta 1-anticollagenase--leukocyte-collagenase complex (latent enzyme) is activatable by disulfide-containing compounds such as cystine, oxidised glutathione, insulin, relaxin, trypsinogen and others, but not by 179,203-di(S-carboxymethyl)trypsinogen, or its trypsin derivative. Compounds containing inaccessible disulfide bonds, e.g. chymotrypsin, or sulfhydryl groups, e.g. D-penicillamine, do not activate the complex. Activation is, however, easily obtained with the oxidised-glutathione-generating system myeloperoxidase/H2O2/glutathione as was previously demonstrated for the human leukocyte latent collagenase activatable in a phagocytosis-simulated respiratory burst [Tschesche, H. and Macartney, H. W. (1981) Eur. J. Biochem. 120, 183-190].
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PMID:Characterisation of beta 1-anticollagenase from human plasma and its reaction with polymorphonuclear leukocyte collagenase by disulfide/thiol interchange. 629 99

It has been previously demonstrated that collagenase activity and collagen synthesis in hepatic granulomas of mice infected with S. mansoni cercariae are maximal 8 weeks after infection; however, total liver collagen content continues to increase. Now the anatomic relationships among collagenase and collagen, granulomas, and hepatic parenchyma in normal mice and in mice infected with S. mansoni are studied. Trypsin-activated collagenase was purified from the media of cultured granuloma explants and anti-collagenase immunoglobulin G was purified from immunized rabbits. The IgG cross-reacted with liver granulomas and active and inactive forms of collagenase, but did not react by immunodiffusion in agar with other neutral proteases or homogenates of schistosome eggs or normal liver. Cryostat sections of liver from normal and infected mice were studied by indirect immunohistochemical methods using fluorescein, rhodamine, and peroxidase labels. Collagenase localization was restricted to areas of collagen deposits in granulomas and hepatic parenchyma. Ultrastructural studies revealed collagenase on the surface of collagen fibers. Hepatocytes of normal mice showed delicate staining at the sinusoidal surface. At all times, immunoreactive collagenase was intimately associated with its substrate, where it presumably initiated collagen degradation. This localization provides a rationale for possible therapeutic approaches to control fibrogenesis through collagenase induction or activation.
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PMID:Immunohistochemical localization of collagenase in hepatic murine schistosomiasis. 629 8

Methods for the isolation of mononuclear phagocytes from human placentas by digestion with collagenase or with trypsin are described. Mononuclear phagocytes were approximately 35% of the cells obtained. Preparations were enriched for mononuclear phagocytes by sequential density gradient centrifugation over Ficoll-Hypaque and Percoll, adherence to plastic and removal of contaminating trophoblastic cells with brief trypsin exposure. Monolayers obtained by these methods were greater than 85% mononuclear phagocytes. These cells were predominantly of fetal origin; most were mature macrophages but up to 20% appeared to be recently derived from blood monocytes as determined by ultrastructural peroxidase cytochemistry.
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PMID:Isolation, purification and characteristics of mononuclear phagocytes from human placentas. 630 Feb 49


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