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)

Benzyl chloride (BCl) is used in the manufacture of basic and acidic dyes, pharmaceutical products, resins, and synthetic tannins. BCl is known to have caused liver malfunctions in some workers exposed to 2 ppm BCl vapors. This study was conducted to investigate the effect of BCl on isolated male rat hepatocytes using several toxicity parameters. The hepatocytes were isolated by a collagenase perfusion technique and were incubated in airtight tubes with 1.8 and 3.6 mM BCl in a shaking water bath at 37 degrees C for 10, 30, 60, and 120 min. Throughout the incubation period the cell viability was determined by trypan blue exclusion and leakage of cytosolic enzymes such as lactate dehydrogenase (LDH), aspartate transaminase (AST), and alanine transaminase (ALT). Exposure to BCl resulted in a significant decrease in cell viability as assessed by trypan blue and significant increase in leakage of these enzymes compared to the controls.
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PMID:Effect of benzyl chloride on rat hepatocytes. 319 58

A method has been developed to prepare free islet cells in suspension from adult ob/ob-mice. About 200 collagenase-isolated pancreatic islets were pooled in 4 ml of calcium-free Krebs-Ringer-HEPES buffer supplemented with 1 mM EGTA and 10 micrograms/ml DNAase. The islets were gently shaken in a water-bath for 10 min at 30 degrees C. Then, the cell suspension was filtered through a nylon screen and centrifuged through ice-cold, dense albumin. The isolated cells, of which more than 99% were B-cells, appeared well preserved both in light- and electron-microscopy. Out of the isolated cells, 7.1 +/- 0.5% took up Evans Blue and were thus considered non-viable.
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PMID:A technique for the isolation of highly viable pancreatic B-cells from ob/ob mice. 352 Nov 79

Hereditary and acquired renal cysts develop from tubule segments that enlarge progressively. We measured the deformability of basement membranes surrounding individual normal tubules and cysts to determine if cysts might develop by simple extension of abnormally-deformable basement membrane in response to normal or increased transtubule hydrostatic pressures. Deformability (cm/dyne) was measured in individual tubules and cysts in vitro by a micropipet aspiration technique that related negative pressures within the pipet to the distance the tubule or cyst wall was aspirated into the pipet. Viscoelastic creep was determined from the time-dependent effect of pipet aspiration on membrane deformation. Proximal and collecting tubules, glomerular capsules and cysts were microdissected from controls and animals with acquired (Diphenylthiazole [rats]. Nordihydroguaiaretic acid [rats]), hereditary (C57 BL/6J [cpk/cpk] mice) and spontaneous (CFWw mice) renal cystic diseases. The major resistance to deformation was localized to the basement membrane since collagenase destroyed the elasticity of tubule and cyst walls. Tubule basement membranes adjacent to cysts appeared abnormal by electron microscopy in the animals fed DPT, but measurements of deformability and viscoelastic creep showed no differences between normal and cystic tubules in any animal model. Deformability values of cysts (7.7 +/- 1.1, 10.9 +/- 1.1, 11.2 +/- 0.6, 9.4 +/- 0.8 X 10(-3) cm/dyne in DPT, NDGA, C57 BL/6J and CFWw, respectively) are consistent with the interpretation that high transtubule pressures ranging from 39 to 134 cm H2O would be required if cysts form by simple stretching of the basement membrane secondary to a transepithelial hydrostatic pressure-gradient. Since in vivo measurements of hydrostatic pressures across cyst walls are not high enough we conclude that cysts do not enlarge due to increased deformability of tubule basement membranes.
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PMID:Viscoelastic properties of tubule basement membranes in experimental renal cystic disease. 365 32

Measurement of chemically induced DNA repair as unscheduled DNA synthesis (UDS) in rat hepatocytes following in vivo exposure has been shown to be a useful indicator of the genotoxicity of chemicals in rat liver. We have examined some of the parameters of this assay in an attempt to increase its sensitivity and reduce cytoplasmic backgrounds. Fischer-344 rats were treated with a low dose of a known positive chemical, water, or corn oil. Livers were perfused with a collagenase solution and isolated hepatocytes were incubated with [3H]thymidine (3H-TdR) followed by overnight incubation in unlabeled TdR, then cell fixation and washing. UDS was measured by quantitative autoradiographic grain-counting as net grains/nucleus (NG). Incubation in 3H-TdR ranging in age from 1 week to more than 12 months gave highly variable background (BKG) and NG counts and a slight overall decrease in NG when the 3H-TdR used was more than 4 months old. Control BKG was 3 times higher after 19 h than after 4 h of incubation in 3H-TdR, with little change in NG. Incubation in unlabeled TdR also reduced BKG significantly. Reduction of autoradiogram exposure from two to one week cut BKG in half without significantly reducing NG. A half-hour wash in fixative (1:3 acetic acid:ethanol) followed by two water washes was as effective in reducing BKG as three 10-min washes in fixative followed by 6 water washes, and resulted in better overall cell attachment. An examination of the distribution of historical control data shows that vehicle control animals never exceed zero NG. This suggests that any NG response greater than zero should be viewed as a possible positive response.
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PMID:Factors that affect the sensitivity of the in vivo-in vitro hepatocyte DNA repair assay in the male rat. 367 Mar 37

Experimental factors implicated in the pathogenesis of halothane hepatotoxicity in the phenobarbital-hypoxia rat model were examined for direct effects on the energy status of isolated rat liver cells in vitro. Intact hepatocytes were isolated after collagenase perfusion of livers of adult male Fischer 344 rats previously treated with phenobarbital (0.1% in drinking water for 5-7 days) and/or deprived of food for 48 h. Cells were incubated in Krebs-Henseleit buffer + substrates for 10 min at steady states of energy metabolism, with extracellular PO2 constant at 32, 16, or 4 mmHg +/- 1% halothane. Fasting produced the largest energy deficits in incubated hepatocytes, regardless of phenobarbital treatment status, PO2 value, or presence/absence of halothane. The combination of hypoxic PO2 (4 mmHg) and 1% halothane shifted lactate metabolism toward lactate production, whereas hypoxia or halothane alone did not. Prior phenobarbital treatment plus hypoxia decreased adenosine triphosphate/adenosine diphosphate (ATP/ADP) and increased lactate production compared with drug treatment or hypoxia alone. We conclude that pathogenic factors that interact to produce halothane hepatotoxicity act directly and jointly on isolated liver cells to produce energy deficits within 10 min. Differences in the relative importance of pathogenic factors in vitro and in vivo suggest that short-term, direct effects on hepatocellular energy status are not solely responsible for halothane hepatotoxicity.
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PMID:Energy deficits in hepatocytes isolated from phenobarbital-treated or fasted rats and briefly exposed to halothane and hypoxia in vitro. 376 35

Aldehyde dehydrogenase (ALDH) was measured in primary cultures of hepatocytes obtained with collagenase perfusion from livers of Long-Evans rats. After seven days in culture, basal ALDH activity, protein content and DNA content are significantly decreased. Exposure of the cultures to phenobarbital (PB, 3 mM in the media) does not prevent the decrease of DNA content, although it keeps protein at relatively higher levels. The activity of ALDH is not only preserved, but also significantly enhanced, when propionaldehyde, phenylacetaldehyde, benzaldehyde and D-glucuronolactone are used as substrates and NAD as the coenzyme. A relative increase of activity is also noted when ALDH is measured with benzaldehyde and NADP. Treatment of Long-Evans animals with PB (1 mg/ml, in drinking water for 2 weeks) leads to similar relative increases of the ALDH activity. In absolute values, however, enzyme activities found after in vivo treatment with PB are higher, compared to those obtained after in vitro exposure. These results show that ALDH activity can be greatly enhanced by PB in primary hepatocyte cultures, free from any indirect endogenous influences.
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PMID:Phenobarbital enhances the aldehyde dehydrogenase activity of rat hepatocytes in vitro and in vivo. 381 68

The effect of various concentrations of fluoride (F-) on cell proliferation, matrix formation and mineralization was examined in hamster molar tooth germs in premineralizing and mineralizing stages. The exposure lasted 16 h (mineralizing stages) and 24 h (premineralizing stages) and the F- levels ranged from 2.63 microM to 2.63 mM; [3H]-thymidine, [3H]-proline, 45Ca and 32PO4 were used as markers for cell proliferation, matrix formation and mineralization, respectively. The proline-labelled amelogenins were isolated by sequential extraction with water and formic acid and their nature examined by SDS-urea-polyacrylamide electrophoresis. Digestion by collagenase was used to assess the amount of proline incorporated into collagens. F- in concentrations up to 1.31 mM inhibited neither biosynthesis of DNA and amelogenins, nor synthesis of collagens and their hydroxylation. Amelogenins extracted from F- induced, non-mineralizing enamel matrix had the same electrophoretic mobility and the same degree of phosphorylation as amelogenins from normal, mineralizing enamel. However, F- increased the uptake of 45Ca and TCA-soluble 32P dose-dependently, starting with 52 microM. Thus, interference with secretion of enamel matrix by F- takes place at much lower concentrations than required to inhibit biosynthesis of enamel matrix.
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PMID:Short-term effects of fluoride on biosynthesis of enamel-matrix proteins and dentine collagens and on mineralization during hamster tooth-germ development in organ culture. 385 37

Hot phenol-water-extracted lipopolysaccharide (LPS) from Bacteroides gingivalis 381 was purified by Sephadex G-100 chromatography with Tris buffer supplemented with sodium deoxycholate and EDTA (B-LPS). In the present study, B-LPS was examined for its ability to induce interleukin 1 (IL-1) production, a mitogenic response, and macrophage activation in LPS high-responder C3H/HeN and low-responder C3H/HeJ mice. A significant increase in IL-1 production was observed in C3H/HeN and C3H/HeJ peritoneal macrophages treated with various doses (1.0 to 50 micrograms/ml) of B-LPS. IL-1 production by C3H/HeN macrophages treated with B-LPS (10 micrograms/ml) was about seven times greater than that by C3H/HeJ macrophages. However, the IL-1 production induced by B-LPS (10 micrograms/ml) in C3H/HeN macrophages was four times lower compared with that induced by Escherichia coli O111 B4 LPS. Also, a significant increase in IL-1 production was found in human monocytes stimulated with B-LPS. That B-LPS-induced IL-1 exhibits some molecular weight heterogeneity was indicated from Sephadex G-75 gel filtration profiles. A significant, high mitogenic response by whole spleen cells with 1 X 10(5) to 5 X 10(4) cells of either mouse strain per well treated with B-LPS (10 to 50 micrograms/ml) was observed. However, the response of C3H/HeJ mice was less than that of the C3H/HeN strain. Also, glucose consumption assays indicated that enhanced macrophage activation occurred in C3H/HeN but not in C3H/HeJ mice treated with B-LPS. In light of recent studies showing that IL-1 stimulates bone resorption in a mouse calvaria system and collagenase production in fibroblasts, we suggest that B-LPS-induced IL-1 may play a significant role in the pathogenesis of adult periodontal disease.
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PMID:Functional role of interleukin 1 in periodontal disease: induction of interleukin 1 production by Bacteroides gingivalis lipopolysaccharide in peritoneal macrophages from C3H/HeN and C3H/HeJ mice. 387 85

Recent electrophysiological and pharmacological studies have confirmed previous clinical evidence that the gene defect in cystic fibrosis is strongly expressed in the sweat gland. This has provided a major impetus to efforts to culture the cells of this tissue in order to provide a source of experimental material for molecular studies. Toward this end, eccrine sweat glands were isolated from collagenase treated skin specimens and the secretory coil and the reabsorptive duct separated. Segments of each portion of the gland were transferred to a plastic or collagen substrate and covered with serum-containing or serum-free defined growth media. Epithelial cell outgrowth took place in both media but fibroblast overgrowth occurred in the presence of serum at concentrations as low as 1%. In serum-free medium both secretory and reabsorptive cells formed tightly joined epithelial sheets, first as monolayers and later as multilayers consisting of at least six cell layers. Growth continued for approximately fifteen generations each of about two and a half days. Remarkably large domes or hemicysts with diameters as great as two cm were formed, apparently attesting to the retention of the capacity of the cells to actively transport ions and water. Ultrastructurally, cells which grew out from the secretory coil resembled the fluid secreting clear cells; neither dark cells nor myoepithelial cells were propagated.
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PMID:Culture of sweat gland epithelial cells from normal individuals and patients with cystic fibrosis. 405 13

Water-soluble proteinpolysaccharides, called PPL, can be extracted from bovine nucleus pulposus in yields of 45%, and from bovine nasal cartilage in yields of 37% of the dry tissue weight. From human costal cartilage only 7% can be extracted. The method used to separate PPL from each of the first two tissues into four distinct fractions separates the PPL of human costal cartilage into four fractions called PPL 3, PPL 4, PPL 5, and PPL 6, which show an increase in protein content, a decrease in chondroitin sulfate content, a nearly constant keratan sulfate content, and an increase in ease of sedimentability and molecular weight. From each of the three tissues mentioned. PPL 3 has a similar amino acid profile and so does PPL 5, but PPL 5 differs from PPL 3 in having a lower content of serine and higher contents of aspartic acid, tyrosine, and arginine. A more extensive effort to characterize these products has been made by analytical ultracentrifugation, and this has led to a further fractionation of PPL 5. Treatment of the cartilage residue or the water-insoluble protein polysaccharide called PPH, with neutral NH(2)OH solution releases water-soluble protein polysaccharides which in composition resemble PPL 4. The water-insoluble residue left after NH(2)OH treatment, when treated with collagenase, yields two soluble products, one resembling PPL 5 in composition, the other with a much lower chondroitin sulfate and much higher keratan sulfate content. The possibility is suggested that in human costal cartilage, binding of some forms of PPL to collagen may occur.
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PMID:The proteinpolysaccharides of human costal cartilage. 423 20


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