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)

A method is described that uses trypsin digestion combined with collagenase-hyaluronidase which produces a population of gap junction vesicles. The hexagonal lattice of subunits ("connexons") comprising the gapjunctions appears unaltered by various structural criteria and by buoyant density measurements. The gap junction vesciles are closed by either a single or a double profile of nonjunctional "membrane," which presents a smooth, particle-free fracture face. Horseradish peroxidase and cytochrome c studies have revealed that about 20% of the gap junction vesicles are impermeable to proteins 12,000 daltons or larger. The increased purity of the trypsinized junction preparation suggests that one of the disulfide reduction products of the gap-junction principal protein may be a nonjunctional contaminating peptide. The gap junction appears to be composed of a single 18,000-dalton protein, connexin, which may be reduced to a single 9,000-dalton peak. The number of peptides in this reduced peak are still unknown.
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PMID:In vitro formation of gap junction vesicles. 5 58

Submandibular glands of 4-week-old rats were dissociated by a procedure involving digestions with collagenase and hyaluronidase, chelation with ethylenediaminetetraacetic acid, and mechanical force. The isolated cells were purified by centrifugation in a Ficoli solution and were maintained in culture for 36 hours. On the basis of trypan blue exclusions, about 70 per cent of the dissociated cells were viable. Electron microscopic observations indicated that the isolated acinar cells and intercalated and striated duct cells retained their essential in situ ultrastructural characteristics. During a 36-hour culture period the number of viable cells declined to about 40 per cent, and the various cell types formed mixed aggregates. The ultrastructural features of the intercalated and duct cells changed relatively little, but the acinar cells revealed several structural alterations. These included a decrease in the number of the secretory granules, fusions of the secretory granules, and an increase in the rough surfaced endoplasmic reticulum. In general, the polarity of acinar cells became less distinct. The endogenous peroxidase activity in the acinar cells gradually diminished during the culture. Isoproterenol when added to the cultured cells failed to stimulate the incorporation of radioactive thymidine or the discharge of the secretory material from the acinar cells.
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PMID:Short term culture of dissociated rat submandibular gland cells. 16 89

The possible direct role of inflammatory cells in resistance to Trichinella spiralis was studied by observing the effects of lamina propria cells from the small intestine (LP cells) of immunized rats on various stages of the parasite. Effects produced by physically disrupted cells were compared to those produced by intact cells on worms exposed to phytohemagglutinin or immune serum. LP cells were isolated from the rat intestine by collagenase digestion of everted gut segments that were previously denuded of epithelium by treatment with hyaluronidase. Disrupted cells, but not intact ones, selectively killed T. spiralis juvenile and adult worms in vitro, whereas larvae were unaffected by similar treatment. Attempts to identify the lethal component of disrupted cells led to an evaluation of the enzyme, peroxidase. Mucosal peroxidase is localized in LP cells and its activity increases several-fold during intestinal trichinosis. It is presumed to be myeloperoxidase, a particulate-bound enzyme of myeloid-derived leukocytes that functions as part of a potent antimicrobial system in combination with H2O2 and a halide. Results indicated that the vermicidal component of LP cells was associated with the pellet fraction of disrupted centrifuged LP cells, but was not linked to a peroxidase-H2O2-halide system.
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PMID:Lethality of disrupted intestinal lamina propia cells for Trichinella spiralis in vitro. 17 21

Bone destruction, commonly associated with chronic otitis media, requires collagen degradation. Collagenase, a neutral protease, appears to be an essential component in the process of collagen breakdown. Collagenase was identified within chronically inflamed and normal guinea pig temporal bones using an immunohistochemical technique with fluorescein isothyocyanate and peroxidase-antiperoxidase labels. Localization of the enzyme identifies sites of matrix resorption. Collagenase was found in osteoclasts, osteocytes, mononuclear inflammatory cells, and at resorbing margins. Inflammation increased the intracellular collagenase content of inflammatory bone osteocytes when compared to normal osteocytes using a microspectrofluorometer. It appears that the inflammatory process directly influences bone destruction through the action of mononuclear inflammatory cells and indirectly by stimulating bone cells to increase their proteolytic enzyme production.
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PMID:Localization of collagenase in chronically inflamed guinea pig temporal bone. 22 7

The ultrastructural mechanism of the protease induced blood-brain barrier permeability-increase was studied with horse-radish peroxidase as a tracer. After intravenous injection of collagenase or pronase, a significantly increased number of pinocytotic vesicles was found in brain capillary endothelial cells. alpha-Chymotrypsine did not exert such an action.
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PMID:Mechanism of action of collagenase on the blood-brain barrier permeability. Increase of endothelial cell pinocytotic activity as shown with horse-radish peroxidase as a tracer. 22 73

Release of peroxidase from secretory cells of rat lacrimal gland upon cholinergic stimulation was studied in vitro with single lobules and isolated cells (lacrimocytes). Isolated lobules, kept in Eagle's medium, remain structurally intact and reaction product of peroxidase is confined to cisternae of rough endoplasmic reticulum, elements of the Golgi apparatus, and all secretory granules. Morphologically, exocytosis occurs by membrane fusion and discharge of granule content. The highest rate of peroxidase released from lobules is observed at 10(-4) M carbamylcholine. The specific activity of peroxidase released into the medium is fourfold higher as compared to the lobules. Release of peroxidase is suppressed by atropine when added before or after the addition of carbamylcholine. At 4 degrees C, no peroxidase release occurs upon cholinergic stimulation. The exocytotic release of peroxidase is dependent on energy supply, as indicated by substantial inhibition (at 37 degrees C) under anoxic conditions or in the presence of dinitrophenol, KCN, or carboxyatractyloside. Furthermore, the process is sensitive to colchicine and vinblastine. Isolated lacrimocytes, consiting of 95% secretory acinar cells, are prepared by digestion with collagenase, hyaluronidase, and trypsin. They retain the characteristic polarity of secretory cells in situ, and localization of peroxidase is the same as in lobules. Since isolated lacrimocytes respond to cholinergic stimulation in the same way as lobules, the receptors are not damaged by the isolation procedure and appear to be associated directly with the exocrine cell. Oxygen uptake by isolated lacrimocytes is about 14 nmol O2 X min-1 X 10(-6) cells; it is about doubled by uncoupling with dinitrophenol. Oxygen uptake rises by 20-30% above the resting rate upon cholinergic stimulation. This additional uptake is suppressed by atropine or by added cholinesterase, indicating that continuous receptor occupancy may be required for the energy demand by exocytosis. On the basis of the specific activity of peroxidase in the medium, the energy demand resulting from cholinergic stimulation is estimated to be 0.08 mumol ATP (or energy-rich phosphate bonds) per microgram of protein released from the lacrimocytes.
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PMID:Exocytosis in secretory cells of rat lacrimal gland. Peroxidase release from lobules and isolated cells upon cholinergic stimulation. 95 71

The aim of this study was to describe the normal distribution of calcitonin gene-related peptide (CGRP) and substance P (SP) containing fibres in the knee joint of the mouse and to obtain insight into the changes in innervation associated with degenerative processes in the joint. Arthrosis was induced by a single subpatellar intra-articular injection of bacterial collagenase. After decalcification in EDTA solutions, the CGRP and SP fibres were visualized by peroxidase-antiperoxidase pre-embedding immunocytochemistry for light microscopy. Control experiments on the mouse brain as a reference for the effect of EDTA on the immunostaining showed that the decalcification procedure with EDTA had not impaired the immunostaining. A rich innervation of thin varicose CGRP and SP immunoreactive fibres was found in most peri- and intra-articular tissue components. The periosteum, synovial tissues, the joint capsule and the intra-articular fat tissues were richly innervated. Less intense innervations were also found in the subchondral bone plates of the tibio-femoral joint and of the patella. Fibres were also found in the soft tissues between the patellar tendon and the femoral groove. No differences could be found between the location of CGRP and SP fibres with respect to the localization in the joint, but generally more CGRP fibres were found. The collagenase-induced osteoarthrosis was characterized by sclerosis of the subchondral bone, patellar dislocation, osteophyte formation, synovial proliferation and by severe cartilage abrasion, particularly on the medial side of the femoro-tibial joint. The overall distribution of CGRP and SP fibres was the same as in the control joints. However, major differences were found in all studied joints at specific locations around the cruciate ligaments, in the synovium around the patella, in the soft tissues lateral of the patella and in plica tissue between the patella and femoral groove. The CGRP and SP innervation was no longer detectable by immunolabelling with the antibodies. With a polyclonal antibody to the growth associated protein GAP-43/B-50, signs of degenerated axonal profiles were observed in these locations. At other peripheral locations, such as the muscles, the GAP-43/B-50 distribution was normal. In conclusion, the present study provides detailed information on the localization of CGRP and SP fibres, which may be involved in pain perception. Knowledge of the changes that occur during arthrosis may give more insight into the clinical symptoms.
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PMID:Calcitonin gene-related peptide, substance P and GAP-43/B-50 immunoreactivity in the normal and arthrotic knee joint of the mouse. 128 63

Mercaptomethylimidazole (MMI) is a potent inducer of gastric acid secretion which is associated with significant inhibition of peroxidase activity of rat gastric mucosa in vivo. A time-dependent increase in acid secretion correlates well with time-dependent decrease in the peroxidase activity. In a chamber experiment in vitro using isolated gastric mucosa, MMI stimulates acid secretion, showing an almost linear response up to 600 microM. The time-dependent increase in acid secretion is also correlated with time-dependent inhibition of the peroxidase activity. This effect is not mediated through oxidation of MMI by flavin-containing mono-oxygenase, which is absent from gastric mucosa. The peroxidase has been localized mainly in parietal cells isolated and purified from gastric mucosa by controlled digestion with collagenase followed by Percoll-density-gradient centrifugation. Peroxidase activity was further localized in the outer membrane of the purified mitochondria of the parietal cell by some membrane-impermeant reagents, indicating outward orientation of the enzyme. MMI can inhibit the peroxidase activity of both the parietal cell and its mitochondria in a concentration-dependent manner. The possible involvement of the parietal-cell peroxidase-H2O2 system in MMI-induced acid secretion may be suggested.
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PMID:Localization of gastric peroxidase and its inhibition by mercaptomethylimidazole, an inducer of gastric acid secretion. 131 28

Gel electrophoretic analysis of the avian tectorial membrane under non-reducing conditions reveals the presence of 2 major proteins with apparent molecular masses of 195 and 41 kDa on 8.25% gels. Under reducing conditions, 6 polypeptides with apparent molecular masses of 146, 60, 56, 43, 35 and 31 kDa are consistently observed. None of these six polypeptides observed under reducing conditions are sensitive to digestion with collagenase, and all, except for the 43 kDa component, are degraded by treatment with cold acidic pepsin. The 60, 56 and 43 kDa polypeptides bind the peroxidase conjugated lectins from Canavalia ensiformis and Triticum vulgaris, indicating the presence of mannose, N-acetyl glucosamine and/or sialic acid. The 146, 60 and 56 kDa bands undergo a shift in electrophoretic mobility after treatment of native tectorial membranes with the enzyme neuroaminidase. Fibronectin and Type II collagen cannot be detected in the avian tectorial membrane by either immunoblotting or immunofluorescence techniques. Polyclonal antisera raised against the different polypeptides after partial purification by one dimensional gel electrophoresis confirm that these proteins are all components of the tectorial membrane, and show that they are restricted to the otolithic and tectorial membranes within the inner ear. Analysis of a wide variety of other tissue types indicates that the 60, 43 and 35 kDa components can only be detected within the inner ear, and that the antisera recognising the 146 and 31 kDa components only show cross-reactivity within the head, with the anti-146 kDa antibodies staining the mucus ducts supplying the olfactory epithelium and the anti-31 kDa antibodies staining granular elements in the cells of the respiratory epithelium. The results suggest that certain of the tectorial membrane components may be novel matrix molecules unique to the inner ear, and that some of the other proteins may be antigenically related to mucins.
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PMID:The protein composition of the avian tectorial membrane. 149 Aug 98

Variation in cell-surface sugar residues which exist between different pancreatic cells has been exploited in an attempt to isolate beta-cells from dispersed porcine pancreas utilizing selective lectin binding. The binding characteristics of a range of lectins were compared to determine their ability to differentiate between endocrine and non-endocrine cells in the porcine pancreas. Histological analysis showed that peroxidase labelled Arachis hypogaea bound selectively to islet cells in Carnoy-fixed sections of pancreas. In five experiments, porcine pancreas was dispersed into single cells by collagenase digestion, incubated with fluorescein isothiocyanate-labelled Arachis hypogaea and analysed using a Fluorescence Activated Cell Sorter. Fluorescein isothiocyanate-labelled Arachis hypogaea bound to a population of cells comprising 6% +/- 4.2% (mean +/- s.d.) of the total. Cells from representative samples were sorted into populations, based on fluorescence. Immunohistochemical analysis of the fluorescent populations showed that 93% +/- 2% of these cells contained insulin: none of the cells stained positive for glucagon or somatostatin. These preliminary studies show that it is possible to separate porcine beta-cells from a dispersed cell preparation using a fluorescent labelled lectin.
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PMID:Separation of beta-cells from dispersed porcine pancreas by selective lectin binding. 181 75


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