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)

Mechanical activity in isolated canine atria hinders impalements of single cells with microelectrodes. However, when atrial contractility becomes diminished, a substantial obstacle to impalement remains. To investigate whether the remaining obstacle could be connective tissue, atria were removed from dogs of three age groups (less than 1 year old, 2.8 +/- 0.2 years old and 10.7 +/- 0.5 years old), perfused arterially, and then immersed in elastase (0.01%) or collagenase (0.1%) for 15 min. The following observations were made: (1) In the older atria, satisfactory cell impalements were attained only after they were treated with elastase or collagenase, (2) elastase was effective on the endocardial surfaces only, and (3) collagenase was effective on the epicardial surfaces only. Enzyme effects corresponded to the known anatomic distribution of elastin (endocardial surface) and collagen (epicardial surface). Therefore connective tissue may present a considerable obstacle to cell impalement, especially in hearts from older dogs.
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PMID:Effects of elastase and collagenase on microelectrode impalements in canine atria at different ages. 609 53

Elastase was used with the HCl method to eliminate extracellular materials such as collagen, basal lamina and elastin for visualization of cell surfaces in the pecten capillary of the chick. The surfaces of the endothelial processes of the pecten capillary were revealed more beautifully by scanning electron microscopy when elastase was applied following HCl treatment than when the HCl-collagenase method was used. In addition, elastase could shorten the incubation time of HCl.
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PMID:Effectiveness of elastase with HCl method for cell surface visualization. 609 83

The NaOH sonication digestion technique permits rapid isolation and exposure of intact networks of elastic fibers in vascular tissue for 3-dimensional observation with the SEM. The configuration of the network of elastic fibers within the vascular wall of large elastic arteries (aorta) is generally agreed to be a flexible framework through which smooth muscle cells and collagenous fibers are interwoven. However, the configuration of elastic fiber networks in muscular arteries, medium sized veins and smaller vessels remains unknown. When the lengthy standard biochemical elastin purification techniques were applied to vessels containing lesser amounts of elastic tissue and finer elastic fibers, the vessels were completely digested. In contrast, the digestion and sonication technique isolated and exposed intact networks of delicate elastic fibers in blood vessels which do not contain large amounts of elastic tissue. Unfixed vessels were cut into short segments, placed in 0.5 N NaOH and sonicated for 20-40 min. The specimens were rinsed in deionized distilled H2O, then autoclaved for 30 min. The tissue was rinsed a second time, fixed and processed routinely for SEM. Elastic stains and enzymatic digestion with chromatographically purified elastase and collagenase confirmed that the digestion and sonication technique produced clean, isolated networks of elastic fibers. Knowledge of the configuration of the networks of elastic fibers in different vessels enhances understanding of distensibility characteristics of individual vessels and serves as a baseline for studying alterations in the elastic framework which occur during aging and disease processes such as atherosclerosis, arterial hypertension and aneurysms.
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PMID:A rapid digestive technique to expose networks of vascular elastic fibers for SEM observation. 620 43

The binding of Evans blue to collagen and elastin in rabbit aortic tissue and in bovine ligamentum nuchae was studied following circulation in vivo of the dye and incubation in vitro in Evans blue containing plasma, respectively. Using collagenase and elastase, the dye was liberated from both tissues corresponding to their different contents of collagen and elastin. Disc electrophoretic analysis of the liberated dye showed, that it migrated as free Evans blue indicating that the binding of the dye to the macromolecules was due to spatial interactions rather than to fixation at specific prosthetic groups. The capability of collagen and elastin to bind Evans blue was demonstrated with the isolated proteins; it was shown elastin had a higher affinity to the dye than collagen. Treatment of the blued tissue with hyaluronidase and Triton X-100 showed that binding to complex carbohydrates and dye accumulation in the aqueous intra- or extracellular space seems to be negligible.
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PMID:The binding of Evans blue to collagen and elastin in elastic tissue. 620 87

Two different subendothelial macromolecules have been identified as being thrombogenic: collagen and the microfibrils associated with elastin. The interaction between platelets and collagen involves the binding of platelet membrane receptors by numerous sites repeatedly staggered along a collagen fiber: this explains why the preservation of ordered structures (quaternary and tertiary structures) is so important in the reactivity of collagen towards platelets. In the case of Type III collagen, a nonapeptide has been identified as possibly being part of these repetitive sites. The microfibrils have not yet been characterized, although the biochemical data presently available show that they are acidic glycoproteins resistant to collagenase. Microfibrils extracted from human placenta or bovine aorta induce the aggregation of platelets in a reaction which involves platelet glycoprotein Ib and FVIII/vWF. A general model proposed for explaining platelet adhesion to subendothelium suggests that two different mechanisms should be envisaged depending on the thrombogenic macromolecules (collagen, microfibrils) involved.
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PMID:The molecular interaction between platelet and vascular wall. 622 98

Glycoproteins from bovine aorta intima were isolated by a sequential digestion of the tissue with collagenase and elastase after extration of the tissue with saline. The proteins in the extracts were precipitated by (NH4)2SO4 and fractionated by Con-A sepharose affinity chromatography. The fractions were analyzed for their carbohydrate composition and by polyacrylamide disc gel electrophoresis. These studies show that considerable heterogeneity of aorta glycoproteins exists. Some of the glycoprotein materials are likely intimately associated with fibrous structures, collagen and elastin, of the aorta intima.
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PMID:Studies of glycoproteins from bovine aorta. 625 71

An insoluble fibrinolytic enzyme with a molecular weight of approximately 30,000, was purified from the human spleen. A single protein band possessing fibrinolytic activity was obtained on polyacrylamide gel disk electrophoresis at pH 4.5. The enzyme, tentatively termed spleen fibrinolytic proteinase (SFP), degraded fibrinogen at neutral pH following Michaelis-Menten kinetics. The fibrinogenolytic activity was not inhibited by t-AMCHA, a specific plasmin inhibitor. SFP barely degraded certain synthetic ester or polypeptide substrates for trypsin, chymotrypsin, plasma, Xa, elastase and collagenase. These results indicate a different nature for SFP compared to other enzymes examined. SFP was found to digest no elastin and its fibrinogenolytic activity was strongly inhibited by STI, indicating that it was not an elastase. SFP required neither Zn++ nor CA++ for its fibrinogenolytic activity, indicating that it differed from metal-dependent proteinases such as collagenase. SFP was inhibited by DFP but not by TLCK, suggesting that it contains an active serine residue, but no trypsin type histidine at its active center. These results appear to show that SFP is a unique proteinase in the spleen, which is capable of degrading fibrin and fibrinogen at neutral pH.
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PMID:Human spleen insoluble fibrinolytic proteinase acting at neutral pH: its partial purification and characterization. 626 69

A gelatin-specific protease from the culture media of human pulmonary alveolar macrophages has been partial purified by gel filtration and characterized. The macrophages were obtained by bronchopulmonary lavage from the lungs of disease-free smoking volunteers. The gelatin-specific protease initially requires trypsin activation. After chromatographing the culture media on a Sephadex G-200 column, trypsin is no longer required for activation. The gelatin-specific protease reported here shares many properties of previously reported gelatinases. It is inhibited by EDTA, cysteine, dithiothreitol and serum. It is unaffected by other protease inhibitors: phenylmethylsulfonyl fluoride, tosyllysine chloromethyl ketone and p-chloromercuribenzoate. Of all substrates tested activity was observed only with gelatin. It was inactive toward collagen, elastin and methemoglobin. This enzyme may have a role in the digestion of collagen which has been cleaved by a mammalian collagenase.
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PMID:Partial purification and characterization of a gelatin-specific protease from the culture media of human pulmonary alveolar macrophages. 626 74

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

Three human basement membranes, glomerular basement membrane (GBM) from renal cortex, alveolar basement membrane (ABM) from lung parenchyma and trophoblast basement membrane (TBM) from the terminal villi of placenta have been isolated by sieving and sonication techniques. Canine GBM and ABM were also prepared. There were marked differences among the membranes from human tissues. Compared to GBM, TBM had very little collagen but contained high concentrations of charged amino acids. ABM was intermediate in composition between GBM and TBM and contained desmosine and isodesmosine indicative of the presence of elastin. Canine ABM (c-ABM) did not contain desmosine or isodesmosine. In the canine system an antigen was detected in ABM which was not present in GBM. The membrane preparations were analyzed for fibronectin content using a specific antiserum to fibronectin. This glycoprotein could not be detected in GBM whereas it was present in ABM in amounts up to 0.8% and in TBM in amounts as high as 7.2%. All the membranes induced the formation of precipitating antibodies in rabbits. Soluble material obtained from the membranes by alkali extraction, reduction of disulfide bonds, enzymatic digestion with elastase, plasmin or collagenase provided immunologically reactive fragments. These soluble fragments gave reactions of identity among the three basement membranes in immunodiffusion reactions in gels with antisera raised to all three BMs. The finding that plasmin digests basement membranes suggests that it may play a role in connective tissue remodeling. The fact that elastase degrades basement membranes provides an endogenous system for injury which may be triggered by infections.
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PMID:Human basement membrane antigens from lung, placenta and kidney. 627 69


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