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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)
To assess the role of inhibitors of proteolytic enzymes, such as plasminogen activator (PA) and
collagenase
in the ovulatory process, inhibitor activity and mRNA levels were examined in periovulatory rat and human ovaries. In the rat, immature animals received 20 IU of pregnant mare serum gonadotropin (PMSG) followed 52 h later by 10 IU of hCG. Ovaries were removed at intervals from 0 to 20 h after human chorionic gonadotropin (hCG) administration. Inhibitor activity for metalloproteinases, such as
collagenase
, increased from 60.5 +/- 4.1 inhibitor units/ovary at 0 h (i.e., time of hCG treatment) to a maximum of 218.2 +/- 11.4 units/ovary at 8 h after hCG before decreasing at 12 h (time of ovulation) and 20 h (122.2 +/- 7.9 and 71.6 +/- 8.1 units/ovary, respectively). Human follicular fluid and granulosa cells were obtained from preovulatory follicles of patients in our in vitro fertilization program. Metalloproteinase inhibitor activity was evaluated in follicular fluid as well as the levels of PA and PA inhibitor (PAI) mRNA by Northern analysis. Increasing metalloproteinase inhibitor activity was positively correlated with follicular levels of estradiol (p less than 0.001) and progesterone (p less than 0.02, N = 26). Chromatographic separation of follicular fluid resulted in two peaks of metalloproteinase inhibitor activity. The large molecular weight (MW) inhibitor had an approximate size of 700 kilodaltons (kDa) and may represent alpha 2-macroglobulin, a serum-derived inhibitor. The small MW inhibitor shared many of the characteristics of tissue-derived inhibitors of metalloproteinases. Partial purification of the small MW inhibitor by Concanavalin A-Sepharose and
Heparin
-Sepharose chromatography demonstrated the inhibitor to be a glycoprotein with an approximate MW = 28-29 K. Northern analysis of human granulosa cell total RNA from preovulatory follicles showed little or no detectable tissue-type PA or urokinase-type PA mRNA. In contrast, two species of PA inhibitor type-1 mRNA were detected in relative abundance. The present findings demonstrate the presence of proteolytic inhibitors in periovulatory ovaries of the rat and human. These ovarian inhibitors may play a role in regulating connective tissue remodeling during follicular rupture.
...
PMID:The role of ovarian proteases and their inhibitors in ovulation. 255 99
The lipoprotein lipase activity in the liver of neonatal (1 day old) rats was about 3 times that in the liver of adult rats. Perfusion of the neonatal liver with
collagenase
decreased the tissue-associated activity by 77%. When neonatal-rat liver cells were dispersed, hepatocyte-enriched (fraction I) and haemopoietic-cell-enriched (fraction II) populations were obtained. The lipoprotein lipase activity in fraction I was 7 times that in fraction II. On the basis of those activities and the proportion of both cell types in either fraction, it was estimated that hepatocytes contained most, if not all, the lipoprotein lipase activity detected in
collagenase
-perfused neonatal-rat livers. From those calculations it was also concluded that haemopoietic cells did not contain lipoprotein lipase activity. When the hepatocyte-enriched cell population was incubated at 25 degrees C for up to 3 h, a slow but progressive release of enzyme activity to the incubation medium was found. However, the total activity (cells + medium) did not significantly change through the incubation period. Cycloheximide produced a time-dependent decrease in the cell-associated activity.
Heparin
increased the amount of lipoprotein lipase activity released to the medium. Because the cell-associated activity was unchanged, heparin also produced a time-dependent increase in the total activity. In those cells incubated with heparin, cycloheximide did not affect the initial release of lipoprotein lipase activity to the medium, but blocked further release. The cell-associated activity was also decreased by the presence of cycloheximide in those cells. It is concluded that neonatal-rat hepatocytes synthesize active lipoprotein lipase.
...
PMID:Lipoprotein lipase activity in neonatal-rat liver cell types. 271 40
Purified mast cells derived from rat peritoneal fluids and dog mastocytomas were extracted with 1 M-NaCl and sonication techniques. The mast-cell products increased the production of mononuclear cell factor from human peripheral blood mononuclear cells in culture, as judged by the enhanced stimulation of prostaglandin E (2-5 fold) and
collagenase
(3-11-fold) production by cultured adherent synovial cells.
Heparin
alone (1-10 micrograms/ml) induced a similar stimulation of mononuclear-cell-factor production by monocyte cultures, whereas histamine (1-10 micrograms/ml) had no effect. The stimulatory effect of mast-cell products and heparin represented a direct effect on mononuclear cells; they did not potentiate the effect of monokine on the synovial cells. These results suggest that mast-cell-macrophage interactions may play a significant role in the pathogenesis of inflammation and connective-tissue degradation.
...
PMID:Mast-cell products and heparin stimulate the production of mononuclear-cell factor by cultured human monocyte/macrophages. 299 97
Certain in vitro culture conditions were determined for equine endothelial cells obtained from the aorta and pulmonary arteries. Cells were enzymatically isolated from the vessel lumen, using clostridial
collagenase
(2.5 mg/ml of Hanks's balanced salt solution) incubated at 37 C for 30 minutes. Cells were cultured in alpha minimum essential medium supplemented with plasma-derived and nonplasma-derived bovine fetal sera, endothelial cell-growth supplement, heparin, and antibiotics. Smooth muscle cell growth was not inhibited with nonplasma-derived animal sera, plasma-derived equine serum, or heparin.
Heparin
and a serum replacement were toxic to the cells used in the present study. Statistically significant differences were not found between the various media supplements.
...
PMID:Equine endothelial cells in vitro. 300 14
Endothelial cells from autopsy and biopsy specimens from a variety of adult human vascular tissue were harvested by
collagenase
treatment and gentle swabbing of the lumenal surface. Nutrient medium MCDB 107 containing a partially purified brain-derived growth factor (5 micrograms/ml), epidermal growth factor (10 ng/ml) and only 2% (v/v) fetal bovine serum supported clonal and long-term serial culture (17.6 to 26.1 cumulative population doublings) of endothelial cells from vena cava, thoracic aorta and tibial arteries at a 70% rate of success. Cumulative doublings of the cell population from eight cultures were inversely proportional to age of donor of the vascular tissue from which cells were isolated.
Heparin
had an enhancing effect on cell growth that varied with cell strain. Prostacyclin production of human adult endothelial cell cultures was stimulated by arachidonate and thrombin by 17 to 20 and 2 to 3-fold respectively. Endogenous and stimulated rates of prostacyclin production by human adult endothelial cells were 2 to 3 times that of human adult smooth muscle cells and 20 to 30 times that of human fibroblasts.
...
PMID:Isolation, growth requirements, cloning, prostacyclin production and life-span of human adult endothelial cells in low serum culture medium. 308 Apr 3
This report describes the development and establishment of long-term serial cultures of adult rat vascular smooth muscle cells (SMC) derived from cerebrocortical resistance vessels (small arteries and arterioles). Electron microscopic examination of microvessels isolated off a 150 microns nylon mesh sieve clearly demonstrated the predominance of these vessel types. Initial outgrowth from
collagenase
-elastase-treated microvessel fragments yielded both endothelium and smooth muscle cells. However, at confluency (2-3 weeks) these cultures consisted of a homogeneous population of broad, polygonal cells that grew in a multilayered "hill and valley" pattern typical of SMC in vitro. For comparative morphological and functional studies, SMC cultures were also initiated from rat thoracic aortas utilizing ring segments as explants. The smooth muscle origin of cultures derived from both resistance vessel (RV) and aorta (RA) was further demonstrated by positive immunofluorescent staining by the specific smooth muscle alpha-actin and myosin antibodies. Ultrastructural examination of these SMC cultures revealed similar morphologic features consisting of typical cytoplasmic myofilament bundles with associated dense bodies and numerous pinocytotic vesicles. Cell growth studies on early (less than P 15)- and late (greater than P 15)-passage RV- and RA-SMC populations revealed markedly different cell growth responses. Representative growth curves of early- and late-passage RA-SMC showed a significantly higher growth rate (two- to fourfold) than RV-SMC cultures. Both cultures, however, exhibited a marked increase in growth potential at higher passage levels.
Heparin
, at a concentration of 100 micrograms/ml inhibited the growth of RV-SMC during the first 3 days after addition in both exponential and growth-arrested culture states, whereas RA-SMC cultures showed no inhibitory response. These studies indicate that long-term RV-SMC cultures can serve as a useful model system to study functional and metabolic properties of this cell type and provide the means to explore further the heterogeneity of SMC derived from different vasculatures in normal as well as various disease states.
...
PMID:Rat cerebral microvascular smooth muscle cells in culture. 353 58
Supernatants from the P388D1 murine macrophage cell line as well as commercially prepared human interleukin-1 (IL-1) stimulated primary rabbit articular chondrocytes to produce collagen- and proteoglycan-degrading proteases. The P388D1-derived factor had a molecular weight of 16,000-20,000 and a pI of 4.5-5.0, and was sensitive to phenylglyoxal treatment. Human IL-1 and the P388D1 supernatants enhanced glycosaminoglycan (GAG) release from bovine nasal cartilage explants. The proteoglycan- and collagen-degrading proteases required Ca2+ for activity. Latent proteoglycanase and
collagenase
had molecular weights of 44,000-56,500 and 34,000-44,000, respectively. The activated proteases had molecular weights of 30,000-40,000 and 22,000-36,000, respectively.
Heparin
-Sepharose affinity chromatography yielded two latent proteoglycanase-degrading protease activities and a collagen-degrading peak. The two proteoglycanase peaks also degraded fibronectin, laminin, gelatin, and azocoll but not type I collagen. The
collagenase
peak also degraded proteoglycan, gelatin, fibronectin, laminin, and azocoll. The activity of the proteoglycan- and collagen-degrading peaks was inhibited by phenanthroline and alpha 2-macroglobulin but not by phenylmethylsulfonylfluoride (PMSF), tosyllysylchloromethylketone (TLCK), pepstatin, or alpha 1-antitrypsin. The control of factors which augment protease production may offer a novel therapeutic approach to arthritis.
...
PMID:Interleukin-1 stimulates the secretion of proteoglycan- and collagen-degrading proteases by rabbit articular chondrocytes. 353 22
The uptake and internalization of a triglyceride emulsion by rat hepatocytes in culture less than 24 hr was either inhibited or uninfluenced by apoE. ApoE significantly increased the uptake of these emulsions in later cultures. Specific low density lipoprotein (LDL) binding was similar for hepatocyte monolayers prior to and after 24 hr. Rat hepatocytes in culture for 2 days, which were treated with
collagenase
, detached and then replated within 1 hr and were apoE-responsive in 2 hr.
Heparin
inhibited the apoE stimulation in both hepatocytes and hepatoma monolayers.
Heparin
wash of hepatocytes or hepatoma cells incubated with apoE-[14C]triolein emulsions at 4 degrees C resulted in a considerable loss in radiolabeled cell lipid. A similar wash after 37 degrees C incubations produced little loss suggesting internalization. Hepatocytes had lower affinity but similar apoE-emulsion binding capacity compared to hepatoma cells. Triolein emulsions with apoE were significantly more rapidly metabolized by the hepatocyte than unsupplemented emulsions. The apoE-mediated hepatocyte lipid uptake was inhibited by apoC proteins. High molar ratios of free fatty acid/albumin also suppressed hepatocyte apoE-mediated lipid uptake. Both rat high density lipoprotein (HDL) and LDL inhibited with a potency directly related to their content of apoE. Human LDL and HDL without apoE also inhibited the interaction with less potency than the rat lipoproteins. Human HDL inhibition was diminished after removal of apoC proteins.
...
PMID:Effect of apoE on triglyceride emulsion interaction with hepatocyte and hepatoma G2 cells. 362 37
Free fat cells and stromal-vascular cells were prepared from rat adipose tissue by incubation with
collagenase
. NH(4)OH-NH(4)Cl extracts of acetone-ether powders prepared from fat cells contained lipoprotein lipase activity but extracts of stromal-vascular cells did not. Intact fat cells released lipoprotein lipase activity into incubation medium, but intact stromal-vascular cells did not. The lipoprotein lipase activity of the medium was increased when fat cells were incubated with heparin, and this was accompanied by a corresponding decrease in the activity of subsequently prepared fat cell extracts.
Heparin
did not release lipoprotein lipase activity from stromal-vascular cells. The lipoprotein lipase activity of NH(4)OH-NH(4)Cl extracts of fat cell acetone powders is increased by the presence of heparin during the assay. This increase is not due to preservation of enzyme activity, but to increased binding of lipoprotein lipase to chylomicrons. Protamine sulfate and sodium chloride have little effect on the binding of lipoprotein lipase to chylomicrons, but they inhibit enzyme activity after binding to substrate has occurred. These inhibitors do, however, inhibit the stimulatory effect of heparin on enzyme-substrate binding.
...
PMID:The mechanism of heparin stimulation of rat adipocyte lipoprotein lipase. 430 30
The effect of zinc deficiency on bone
collagenase
activity and collagen turnover was studied in the chick. Zinc deficiency symptoms, evident after 8 days on the low zinc diet, included tibia deformities and decreased alkaline phosphatase. Bone collagen metabolism was markedly altered, with a significant reduction in collagen synthesis and turnover. Half-turnover time for tibia collagen was 13 days in the control and 35 days in the zinc-deficient chicks. Tibia
collagenase
activity was reduced by 40-80% in the zinc-deficient as compared to the control chicks.
Heparin
markedly increased
collagenase
activity in the zinc-deficient tibias elevating activity to control levels. But commercially available heparin was found high in zinc content which may explain this effect entirely. These data show that zinc deficiency decreases bone collagen turnover and probably accounts for the leg deformities seen in zinc-deficient chicks.
...
PMID:Effect of zinc deficiency on bone collagenase and collagen turnover. 625 4
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