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 monospecific rabbit anti-rat uterus collagenase antibody has been prepared and used to study the distribution of the enzyme in the rat uterus during postpartum involution. Cryostat sections of rat uteri from 24 to 240 hours postpartum were stained by the indirect immunofluorescent method. Nonpregnant rat uterus revelaed positive staining in basement membranes, in endometrial stroma, in perimuscular and in vascular connective tissue. During postpartum involution of the uterus two types of changes in uterine collagenase were observed: (1) variations in the distrubiton of the enzyme, which became selectively localized in the epithelial basement membrane and in the wall of small blood vessels, and (2) variations in the overall intensity of fluorescent staining, which decreased immediately after delivery and slowly increased back to nonpregnant levels in 5 days. The significance of these findings is discussed in relation to the mechanisms of control of collagenase activity in vivo.
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PMID:The distribution of collagenase in the rat uterus during postpartum involution. An immunohistochemical study. 17 37

An enzyme capable of digesting native collagen in solution at neutral pH was extracted from the 6 000 times g sediment of the involuting uterus of the mouse and of the back skins of mice and rats. The collagenase could be dissociated at cold-room temperature from the sediment in about equal amounts when neutral Tris buffer containing 1.0M NaCl or 5M urea was used for the extraction step. The enzyme has been concentrated by ammonium sulfate precipitation and the activity was measured by using [14C]collagen in solution at pH 7.5. Collagen breakdown products were identified by disc electrophoresis. The amount of enzyme extracted was a function of temperature and salt concentration. As 5M urea extracted collagenase from the sediment in a relatively short time, this method of extraction seems to be a useful tool for serial experiments in the study of collagenase activity in collagen-rich tissues.
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PMID:Extraction of collagenase from the 6000 times g sediment of uterine and skin tissues of mice. A comparative study. 17 Jan 81

A rabbit monospecific anti-rat uterus collagenase antibody has been used to study the distribution of collagenase in normal rat tissues by immunohistochemical methods. Indirect staining was performed with fluorescein-conjugated goat anti-rabbit immunoglobulin G antibody. The organs studied were brain, lung, myocardium, liver, spleen, kidney, adrenal, testes, uterus, xiphoid cartilage, tail tendon, skeletal (triceps) muscle and skin. Collagenase is widely present throughout the connective tissue structures in all organs examined. The enzyme is apparently bound to collagen fibers, reticulum fibers and basement membranes. The results suggest that control of collagenase activity depends on factors other than the presence of the enzyme in tissues.
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PMID:The distribution of collagenase in normal rat tissues. 17 56

Collagenase (EC 3.4.24.3) activity can be measured directly in homogenates of the involuting rat uterus. Latent forms of collagenase are activated by a brief exposure to trypsin; trypsin activity is then blocked with soybean trypsin inhibitor. Homogenizing conditions have been developed that permit 90-95% recovery of the total active and latent collagenase activity in a 6000 X g pellet, where it is presumably bound to its collagen substrate. This insoluble activity can then be extracted by heating to 60 degrees C for 4 min in 0.04 M Tris - HCl buffer, pH 7.5, containing 0.1 M CaCl2. Methods are presented for the estimation of the recovery of collagenase in the extracts; this approximates 65-70% of the total. Small amounts of activity can also be extracted from rat liver and kidney. This extraction procedure should be of use in purifying collagenase without culturing the enzyme-producing tissue and in the direct assay of tissue collagenase activity. The activity extracted from rat uterus has been proven to be collagenase by its characteristic pattern of collagen breakdown products on disc electrophoresis and by the split of tropocollagen at interband 41 as shown by electron microscopy of reconstituted fragments. The activity is inhibited by EDTA, and this inhibition is not reversed by calcium or zinc ions.
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PMID:Extraction of collagenase from the involuting rat uterus. 18 74

1. The involuting rat uterus displays an extremely rapid breakdown of collagen. Collagenase activity can be assayed directly in the insoluble 6000g pellet of uterine homogenates. At 1 day post partum, about 85% of this collagenase activity is in a latent form. 2. This latent form can be activated by trypsin or by a serine proteinase present in the uterine pellets. 3. The activating enzyme of the tissue is inhibited by a wide spectrum of trypsin inhibitors, including Trasylol, soya-bean and lima-bean trypsin inhibitors, snail inhibitor and di-isopropyl phosphoro-fluoridate. Partial inhibition is produced by benzamidine, phenylmethanesulphonyl fluoride, epsilon-aminohexanoate, leupeptin, antipain and alpha1-antitrypsin. Ovomucoid, 7-amino-1-chloro-3-tosylamido-1-heptan-2-one and 1-chloro-4-phenyl-3-(N-benzyloxy-carbonyl)amino-L-butan-2-one are not inhibitory. 4. Extraction of uterine pellets with 0.1 M-CaCl2 at 60 degrees C releases both latent and active collagenase. Exclusion chromatography on Sephadex G-100 gives an apparent molecular weight of approx. 77000 for the latent form and 66000 for the active form. The latent form is suggested to be a zymogen of collagenase.
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PMID:A latent form of collagenase in the involuting rat uterus and its activation by a serine proteinase. 19 99

As tissue cultures, rabbit bone, skin and non-gravid uterus synthesise inhibitors of collagenase (EC 3.4.24.3). An assay for the inhibitors is described and their action on collagenase from different tissue sources demonstrated. Evidence for the involvement of the tissue inhibitors of collagenase in the latency of the enzyme in culture media is presented. Latent collagenase was activated by treatment with 4-aminophenylmercuric acetate, and then reacted with the inhibitors to form inactive complexes with properties similar to the naturally occurring latent enzyme forms. The associated changes in molecular weight are detailed, and discussed in relation to the observations of other workers concerning the extracellular control of collagenase activity.
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PMID:The detection and characterisation of collagenase inhibitors from rabbit tissues in culture. 19 53

Collagenases (EC 3.4.24.3) from human skin, rat skin and rat uterus were inhibited by the chelating agents EDTA, 1,10-phenanthroline and tetraethylene pentamine in the presence of excess Ca2+, suggesting that a second metal ion participates in the activity of the enzyme. Collagenase inhibition by 1,10-phenanthroline could be both prevented and reversed by a number of transition metal ions, specifically Zn2+, Co2+, Fe2+ and Cu2+. However, Zn2+ is effective in five-fold lower molar concentrations (1-10(-4) M) than the other ions. Furthermore, Zn2+ was the only ion tested able to prevent and reverse the inhibition of collagenase by EDTA in the presence of excess Ca2+. Atomic absorption analysis of purified collagenase for Zn2+ showed that Zn2+ was present in the enzyme preparations, and that the metal co-purifies with collagenase during column chromatography.
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PMID:Evidence for mammalian collagenases as zinc ion metalloenzymes. 19 65

The presence and distribution of collagenase in experimental CCl4 cirrhosis of the liver in rats has been studied by immunohistochemical techniques. A monospecific anti-rat uterus collagenase antibody was raised in rabbits and used for indirect immunofluorescence staining of liver sections obtained from rats in both the reversible and irreversible stages of CCl4-induced cirrhosis. Collagenase is present assoicated with connective tissue septums as long as cirrhosis is reversible, and it is not detectable in the irreversible stage. In animals sacrificed during the transition between the reversible and irreversible stages of cirrhosis, collagenase appeared bound to the outer surfaces of connective tissue septums and was absent from the deeper portions. These observation suggest that the irreversibility of experimental CCl4 cirrhosis of the liver is associated with a disturbance in the mechanisms of collagen degradation, which may be a deficiency in collagenase activity, a change in the susceptibility of the substrate, or a combination of both factors.
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PMID:Collagenase in experimental carbon tetrachloride cirrhosis of the liver. 20 92

The steady decline in plasma progesterone level that occurs during the last week of pregnancy in the normal rat (Wiest, '70) provides good opportunity to study the effect of withdrawal of progesterone on uterine differentiation. Evidence is presented that tissue monocytes, heterophils, and eosinophils are regular components of the normal late gestational uterus and that their number increases as term approaches. Uterine monocytes and heterophils are located in the endometrial and myometrial stroma as well as within the basal intercellular compartment of the luminal epithelium. Stromal monocytes are distributed throughout the attenuated endometrium of late gestation, but are more common immediately beneath the luminal epithelium. In the myometrium, monocytes and heterophils occur, often as perivascular, clusters in the connective tissue septum that separates the two layers of smooth muscle. Eosinophils are present especially in the deep endometrial and myometrial stroma, and increase in number as plasma estrogen rises immediately before parturition. A small population of lymphocytes is regularly present. An important feature of the prepartum uterine stroma is the sparseness of macrophages. Near term, however, the beginnings of monocytic-macrophagic transformation are noticeable as the cell surface becomes more irregular and organelles associated with endocytic activity arise. The prepartum monocytes are positioned in the same histological sites that during the postpartum period of regression will be occupied by macrophages (Padykula and Campbell, '76). Since it is generally accepted that monocytes are precursors of macrophages, this spatial correlation raises the possibility that cellular preparations for regression commence before birth. The possible significance of prepartum monocytic infiltration is discussed in relation to the effect of changing plasma and uterine concentrations of progesterone on uterine collagenase activity. The steady increase in uterine leucocytes which occurs concomitantly with decreasing uterine binding capacity for progesterone supports the hypothesis by Siiteri et al. ('77) that progesterone in high local concentrations has an anti-inflammatory effect.
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PMID:The occurrence of uterine stromal and intraepithelial monocytes and heterophils during normal late pregnancy in the rat. 21 76

In the present paper we report on an improved procedure for the preparation of free uterine cells which avoids the use of trypsin and employs very low concentration of collagenase. The cells released mechanically from the digested tissue are constantly removed from the enzyme containing medium, thus minimizing exposure to collagenase. 60%-70% of the cells which make up the intact uterus are obtained as free cells and 95% of these cells are viable for at least 15 hours at 37 degrees. Metabolic integrity was assessed by measuring the cell's ability to oxidize glucose and synthesize proteins over extended periods of time. The membrane leucine carrier protein and the membrane Na+/K+ ATPase were found to be fully functional. Electron microscopic analysis of the cells confirmed their structural integrity. Data are presented illustrating that with this system the estrogen binding protein is stable at physiological temperatures. The cells contain approximately 30,000 specific estrogen binding sites, with an apparent KA of 5--6 x 10(9) M-1. At 37 degrees 80% of the hormone receptor complexes were in the nuclear fraction, 20% in the cytoplasm. The similarity of the estrogen receptor binding parameters with those measured in the intact tissue after in vivo hormone adminsistration, together with the cells' structural and metabolic integrity make this procedure for the preparation of uterine cell suspensions in high yields particularly suitable for studies in which minimal cell injury is an essential prerequisite.
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PMID:An improved procedure for the preparation of rat uterine cell suspensions. 22 Jul 54


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