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)

The occurrence of intracellular fibrillar material (frequently banded) has been studied in normal costal and tracheal chondrocytes of rats at various ages ranging from 1 to 90 days. The study methods have included digestion with collagenase, electron histochemical techniques and routine electron microscopy. Banded fibrillar material has been observed intracellularly in vesicles or in electron-dense bodies in perichondrial and subperichondrial chondrocytes from rats of all ages. These fibrils and extracellular collagen fibrils are partially and equally degradable by collagenase, they are positive after staining with phosphotungstic acid or with silver nitrate methenamine, and their lucency corresponds with that of collagen when they are stained only with lead citrate. They have not been observed in intracellular clefts. They, therefore, seem to be formed intracellularly and to be exocytosed subsequently. Large vesicles and electron-dense bodies seem to be derived from Golgi saccules. A mechanism whereby banded intracellular fibrils could be formed from tropocollagen molecules is postulated. The frequency of occurrence and the diameter of intracellular fibrils seems to increase with increasing age.
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PMID:Periodic fibrillar material in intracellular vesicles and in electron-dense bodies in chondrocytes of rat costal and tracheal cartilage at various ages. 5 69

Nine cultures of fibroblast cell types and 13 epithelial-like cell types were maintained for 1 week in media supplemented with L-asborbic acid (50 microgram per ml). All fibroblast-like cultures produced extracellular fibers that stained positively by a silver-impregnation reticulin stain. Nine of the 13 epithelial-like cultures produced fibers that stained positively for reticulin. Nearly all cultures not supplemented with ascorbic acid showed no fiber staining. Those few lines that stained positively for reticulin in the absence of ascorbic-acid supplementation demonstrated only slight reticulin formation. Reticulin from one fibroblast culture and one epithelial culture was examined by electron microscopy, and the silver-impregnated fibrils were morphologically identical to collagen. The reticulin was digestible with collagenase, providing further evidence that the silver-impregnation reticulin stain identifies collagen in culture. The demonstartion of collagen can be performed easily in histology laboratories using Formalin-fixed cells, and provides a means of assaying a functional property of cells in culture which is characteristic of connective tissue fibroblasts in general as well as certain specialized epithelia.
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PMID:Histochemical demonstration of collagen fibers in ascorbic-acid-fed cell cultures. 8 Mar 77

A peptidase cleaving a synthetic substrate for collagenase, 4-phenylazobenzyloxycarbonyl-L-Pro-L-Leu-Gly-L-Pro-D-Arg (designated as PZ-peptide) has been purified extensively (about 5200-fold) from a soluble extract of monkey kidney with a view of carrying out studies on its possible physiological role. The purified PZ-peptidase appeared essentially free of collagenase, nonspecific protease and di- and tri-peptidase activities. The properties of the purified PZ-peptidase resemble very much the granuloma enzyme. It is optimally active around pH 7.0. Its apparent Km value for PZ-peptide is 0.72 mM and V is 10.1 mumol/mg protein/min. It is reversibly inhibited by p-hydroxymercuribenzoate and HgCl2, whereas iodoactetamide does not affect the enzyme activity. N-Ethylmaleimide inhibited the enzyme partially (50%). Heavy metals like Cu-2+, Cd-2+, Ag+, Pb-2+, Ni-2+, and Zn-2+ completely inhibited the enzyme activity, while the inhibition by Co-2+ was only partial. Fe-2+ did not exert any effect on the activity. The enzyme activity was completely inhibited by EDTA and was restored almost to the original value by metal ions like Mn-2+, Mg-2+, Ca-2+ and Ba-2+. The approximate molecular weight of the purified enzyme was estimated to be 56 000.
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PMID:Purification and properties of a peptidase acting on a synthetic substrate for collagenase from monkey kidney. 16 32

Arterial endothelial cells were obtained from bovine aortae by mild treatment with collagenase and medium perfusion. These cells were cultured in RPMI-1640 medium containing 15mM Hepes buffer and 35% fetal calf serum at pH 7.35. Essentially all (90-95%) the effluent cells were viable and 80% of these cells attached to the substratum within 1 hour. Small patches of attached cells coalesced to form confluent monolayers in 3-5 days. Confluent monolayers of endothelial cells consisted of a homogeneous population of tightly packed, polygonal cells. Selected cultures were serially subcultured (trypsin-EDTA) for 12-14 months (30-35 passages) without any apparent change in morphology or loss of growth characteristics. Primary and three-month old (15 passages) cultures had population doubling times of 32-34 hours and 29-31 hours, respectively. These cells (primary and subcultures) did not require a minimum cell number to become established in culture. Bovine endothelial cells (primary, first, fifth and thirteenth passages) were characterized ultrastructurally by the presence of Weibel-Palade bodies, pinocytotic vesicles and microfilaments and immunologically by the presence of thrombosthenin-like contractile proteins and Factor VIII antigen. The intercellular junctions of post-confluenct cultures stained specifically with silver nitrate. From these data, we concluded that identifiable endothelial cells could be obtained from bovine aortae and cultured and maintained for prolonged periods of time.
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PMID:Culture of arterial endothelial cells: characterization and growth of bovine aortic cells. 17 37

In order to elucidate the cytochemical properties of the membranous structure between enamel and ameloblasts of the rat incisor at the maturation stage, chromic phosphotungstic acid (Cr-PTA) and periodic acid-silver methenamine (PA-silver) techniques for electron microscopy were employed in combination with a digestion test with hyaluronidase, neuraminidase, collagenase or trypsin. Also, acid phosphatase activity of ameloblasts at the maturation stage was examined with a modified GOMORI's metal salt method. An intensely Cr-PTA reactive band approximately 0.1 micron thick appeared along the surface layer of enamel at the transitional stage, and at the very beginning of the maturation stage another intensely Cr-PTA reactive band which was seen by uran-lead stain to be a delicate electron-dense membranous structure appeared as well between enamel and ameloblasts. A lot of cytoplasmic small vesicles or tubular structures, both intensely reactive to Cr-PTA, were observed near the apical membranes of the overlying ameloblasts indicating that those organelles must have been responsible for the secretion of the latter band. Acid phosphatase activity was clearly demonstrated at Cr-PTA reactive large vesicles in the cytoplasm of those cells. The PA-silver staining technique manifested a band heavily deposited with silver grains along the surface layer of enamel, i.e., where the former band existed, but showed no particular reaction at the latter, the band-like layer between enamel and ameloblasts. Hyaluronidase or neuraminidase treatment remarkably decreased the Cr-PTA reaction of the latter band. Trypsin or collagenase treatment, on the other hand, not only eliminated the Cr-PTA reaction but digested the band itself. These results suggest that the membranous structure between enamel and ameloblasts of a rat incisor is not so-called enamel cuticle but a basal lamina produced by overlying ameloblasts and that the basal lamina contains collagenous components even though it lies on enamel.
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PMID:Cytochemical studies of ameloblasts and the surface layer of enamel of the rat incisor at the maturation stage. 21 3

Percutaneous liver biopsies obtained from patients with a history of chronic alcoholism and normal liver, fatty liver, alcoholic hepatitis, or active cirrhosis were incubated with tritiated proline to determine the pattern of collagen biosynthesis in these conditions. Incorporation of labeled proline and hydroxyproline into salt-soluble and insoluble fractions of collagen was evaluated by radiochemical analysis and tissue localization documented by autoradiography. Biopsy specimens of alcoholic hepatitis and cirrhosis exhibit a significant increase in the amount of radioactive proline and hydroxyproline in salt-soluble and insoluble collagen. Marked accumulation of radioactivity occurred over bile ducts, fibroblasts, and collagen fibers in the portal area and over hepatocytes, fibroblasts, and collagen fibers in the centrilobular area. Fatty liver is associated with an increase in uptake of proline and hydroxyproline in the salt-soluble fraction of collagem; silver grains appear in the periphery of fat-laden cells and in areas of focal inflammation. Digestion by collagenase indicates that labeling over fibroblasts and collagen reflects active synthesis, whereas, entry of proline into the cell protein pool is responsible for accumulation of radioactivity in other sites. In vitro ethanol causes a significant increase in the incorporation of proline and hydroxyproline into collagen in biopsy specimens of alcoholic hepatitis or active cirrhosis, but has no effect on collagen synthesis by normal or fatty liver.
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PMID:Collagen biosynthesis in liver disease of the alcoholic. 117 Feb 67

The existence and significance of Von Korff fibers during early dentinogenesis are still very controversial. The purpose of the present study was to re-examine the questions of the existence, nature and significance of Von Korff's fibers using light microscopy and immunohistochemistry. Specimens were obtained from 3 days-old CD-I mice and mandibles were carefully dissected under constant irrigation and immediately fixed in 10% neutral buffered formalin for light microscopy. Sections were treated or not with collagenase prior to silver staining. For immunohistochemistry, specimens were fixed in 95% ethanol and embedded in paraffin. Sections were reacted with goat anti-human-bovine type I or type III collagen and a rhodamine (RITC) labelled rabbit anti-goat IgG was then reacted as a secondary antibody. Slides were then examined under a Zeiss II photomicroscope equipped with epifluorescence. Our results have confirmed the presence of argyrophilic material concentrated at the periphery of the dental papilla and stretching from the subodontoblastic layer to the future dentino enamel junction. The distribution of type III collagen was very similar to the distribution of the silver staining at the cervical loop area. Type I collagen distribution was different and concentrated in areas where odontoblasts were fully differentiated. Our study showed that Von Korff fibers are not artefactual. We have established the presence of an apical compartment containing type I collagen fibers and a basal compartment containing type III collagen to explain the image of continuous silver staining crossing the entire thickness of the odontoblast layer.
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PMID:Investigation of the role of Von Korff fibers during murine dentinogenesis. 128 7

Twenty Wistar rats were injected with cortisone acetate twice a week subcutaneously for 6-12 wks. By 7 weeks Pneumocystis carinii pneumonia was induced in rats successfully. The cysts of Pneumocystis carinii from infected lungs of cortisonized rats were identified by phase-contrast microscopy, Giemsa's stain, Chalvardjian's stain and Gomori's methenamine silver nitrate stain. The process of isolation and purification of Pneumocystis carinii from infected rat lungs included the following three test steps. First, the tissue was cut into small pieces and homogenized and filtered through #60, #100, #200-gauge wire mesh respectively. Secondly, the homogenate was digested with collagenase, the optimal concentration of collagenase being 0.2%. Thirdly, the discontinuous percoll density gradient centrifugation was used to separate P. carinii cysts. The majority of P carinii cysts were present in a density zone of approximately 1.033g/ml and were essentially free from host lung debris, the latter being removed due to their higher density, 1.040g/ml.
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PMID:[Isolation and purification of Pneumocystis carinii cyst]. 130 67

An inhibitor of neovascularization from the conditioned media of scapular chondrocytes established and maintained in serum-free culture has been isolated and characterized. To determine whether this chondrocyte-derived inhibitor (ChDI) was capable of inhibiting neovascularization in vivo, this protein was assayed in the chick chorioallantoic membrane assay. ChDI was a potent inhibitor of angiogenesis in vivo (4 micrograms = 87% avascular zones). This inhibitor is also an inhibitor of fibroblast growth factor-stimulated capillary endothelial cell (EC) proliferation and migration, as well as being an inhibitor of mammalian collagenase. ChDI significantly suppressed capillary EC proliferation in a dose-dependent, reversible manner with an IC50 (the inhibitory concentration at which 50% inhibition is achieved) of 2.025 micrograms/ml. Inhibition by ChDI of growth factor-stimulated capillary EC migration was also observed using a modified Boyden chamber assay (IC50 = 255 ng/ml). SDS-PAGE analysis followed by silver staining of ChDI purified to apparent homogeneity revealed a single band having an M(r) of 35,550. Gel elution experiments demonstrated that only protein eluting at this molecular weight was anti-angiogenic. These studies are the first demonstration that chondrocytes in culture can produce a highly enriched, potent inhibitor of neovascularization which also inhibits collagenase.
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PMID:Isolation and characterization of an inhibitor of neovascularization from scapular chondrocytes. 138 32

The purpose of this study was to investigate the role of the endothelium in regulating lymphatic contractile activity in bovine mesenteric truncal lymphatics. To test the effects of endothelial denudation on lymphatic pumping, bovine lymphatics were suspended in an organ bath preparation with the vessels cannulated at both inflow and outflow ends. By raising the heights of the Krebs reservoir and the outflow catheters appropriately, a transmural pressure could be applied to the vessels. The relationship between transmural pressure and fluid pumping is expressed as a bell-shaped curve with pumping increasing up to a peak pressure (between 8 and 12 cm H2O), and declining at pressures above this level. We compared pressure/flow curves in endothelium-intact and endothelium-denuded vessels. Chemical methods to remove the endothelium were attempted (collagenase and dispase) but were unsuccessful since they resulted in inhibition of all contractile activity including that induced with KCl. A technique using suture silk (3-O to 6-O) threaded into PE 50 or PE 20 polyethylene catheters with a loop at one end proved to be effective. By passing the catheter with its exposed loop of silk through the lymphatic ducts and imparting a twisting motion, we were able to remove the endothelium and preserve the smooth muscle responses to KCl. Transmission electron microscopy as well as silver staining techniques confirmed that all of the endothelium had been removed leaving the subendothelium and smooth muscle undamaged. We established that removal of the endothelium had no effect on lymphatic pumping. Pumping could not have occurred without the normal function of the one-way valves indicating that the denudation procedures did not damage these elements. Maximum flow rates and the transmural pressures that induced peak flows were similar in the two groups. We conclude that the pumping activity of bovine mesenteric truncal lymphatics in response to transmural pressure changes does not depend on an intact endothelium.
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PMID:Is endothelium necessary for transmural pressure-induced contractions of bovine truncal lymphatics? 158 57


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