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)

Rat submandibular gland cells have been obtained through enzymatic dispersion using chromatographically purified collagenase (EC 3.4.24.3) and hyaluronidase (EC 3.2.1.35) and gentle mechanical force. The recovery of viable cells after the isolation procedure was 59% on the basis of total glandular DNA content. Approximately 60% of the total cell population consisted of acinar cells; less than 8% were immature granular duct cells; and the remainder were intercalated duct, striated duct, and myoepithelial cells. Most of the acinar cells were in acinar-intercalated duct complexes. The integrity of the isolated cells was substantiated by their exclusion of trypan blue, intracellular electrolyte composition, incorporation of [14C]glucosamine into trichloroacetic acid + phosphotungstic acid precipitable material at a linear rate for 1.5 hr, secretory responses to parasympathomimetic and sympathomimetic stimulation, and morphologic integrity as determined by light and electron microscopy. The cholinergic receptors were characterized through investigation of the net transmembrane flux of K+ in response to carbamoylcholine. The alpha-adrenergic receptors were characterized by investigating the net transmembrane flux of K+ in response to norepinephrine stimulation and the beta-adrenergic receptors were characterized by determining the rate of secretion of 14C-labeled mucin after isoproterenol stimulation. A high degree of sensitivity to both cholinergic and adrenergic secretagogues was observed.
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PMID:Functional characteristics of dispersed rat submandibular cells. 22 58

A series of intracellular events occurring after treatment of rabbit synovial fibroblasts with 0.01 micrograms/ml phorbol myristate acetate (PMA) were measured. Ten minutes after addition of PMA, there was a temporary increase in intracellular cyclic AMP levels, followed by a transient decrease in incorporation of 3H-thymidine into DNA. Approximately 500 ng/mg cell protein of PGE2 were found in culture medium from the 12- to 24-hour incubation period, but significant collagenase was not detectable until 24 to 36 hours. Treatment with aspirin or indomethacin abolished PGE2 production but did not affect collagenase levels. Production of enzyme was associated with a cessation of cell proliferation, measured by protein content/culture and cell number. No enzyme was detectable in untreated cultures. Synovial fibroblasts treated with phorbol myristate acetate may provide a good model for studies on the mechanism of induction of collagenase production.
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PMID:Collagenase production by synovial fibroblasts treated with phorbol myristate acetate. 22 97

Pancreatic islets from C57BL/KsJ-db/db, and +/+ mice were isolated by collagenase. After isolation the islets were transferred to a hypotonic ethidiumbromide solution with 0.3% of the detergent Nonidet P40. After vortexing, the samples were analyzed in a BioPhysics Cytofluorograf 4802A. The DNA histograms were divided into 2c, 2-4c, 4c and 8c fractions under the assumption of a constant rate of DNA synthesis during the 2-4c phase. In comparison with normal mice, we found that diabetic mice had a lower fraction of 2c nuclei and a higher fraction of 2-4c, 4c, and 8c nuclei. These results obtained by flow cytometry are in agreement with results obtained by 3HTdR incorporation and by cytophotometry on histological sections.
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PMID:Flowcytometric evaluation of the DNA distribution in isolated pancreatic islets from normal and diabetic mice. 37 3

Suspensions of endocrine pancreas cells were prepared by shaking collagenase-isolated rat islets of Langerhans in calcium-free buffer. When incubated with 1.0 mM substrate at pH 7.4, the cells split Pi from 5'-AMP at a rate of 87 nmol/h per microgram DNA, and from beta-glycerophosphate at a rate of 25 nmol/h per microgram DNA. Km for 5'-AMP was about 54 microM. Adenosine or theophylline inhibited the 5'-AMP hydrolysis. Homogenization of the cells increased the activity toward 5'-AMP by 23% and that toward beta-glycerophosphate by 115%. Injecting rats with cortisone had no effect on the 5'-AMP hydrolysis by whole cells but significantly increased the activity in cell homogenates; the intracellular activity toward 5'-AMP was more than doubled by the cortisone treatment. Staining whole islet cells for 5'-AMP-splitting activity resulted in a demarcation of the cell periphery in control rats. Cells from cortisone-treated rats showed heavier deposits of reaction product, and their cell periphery did not stand out as clearly. It is suggested that 5'-nucleotidase is largely an ectoenzyme in normal rat islet cells. The cells also contain an as yet unidentified intracellular phosphatase that seems to be solely responsible for the increased hydrolysis of 5'-AMP in cortisone-treated rats.
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PMID:5'-AMP hydrolysis by suspensions and homogenates of pancreatic islet cells from normal and cortisone-treated rats. 38 76

The direct effects of porcine insulin and glucagon on bone collagen and non-collagen protein synthesis have been examined in cultures of calvaria obtained from 21-day fetal rats. Bones were incubated for 24 to 96 h and [3H]proline was added for the last 2 h of culture. Incorporation of the label into collagenase-digestible protein (CDP) and noncollagen protein (NCP) was determined using purified bacterial collagenase. Insulin increased the labeling of CDP by 60 to 115% at concentrations of 10(-9) to 10(-6) M. A smaller stimulatory effect was observed on NCP. The effect on CDP appeared after 12 to 24 h of culture, was maintained for 96 h in the continuous presence of the hormone, but was lost within 3 h of removal of insulin from the culture medium. Insulin appeared to have a direct effect on collagen synthesis and not on collagen breakdown. Insulin did not affect the incorporation of [3H]uridine or [3H]thymidine into the RNA and DNA fractions of bone at 24 h. Insulin opposed the inhibitory effects of parathyroid hormone and dibutyryl cyclic-3',5'-adenosine monophosphate and to a lesser extent, the inhibitory effect of isobutylmethylxanthine on the labeling of CDP. Glucagon did not affect the response to insulin and by itself had small and variable inhibitory effects on proline incorporation.
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PMID:Hormonal control of bone collagen synthesis in vitro. Effects of insulin and glucagon. 40 59

Converting enzyme activity was studied in endothelial cells, isolated from pig pulmonary arteries and aorta by exposure to collagenase. The measure was based on the release of His-Leu from Z-Phe-His-Leu was related to the DNA content of the cellular suspension. The same activity was found in the two types of endothelium: 1 nmol His-Leu/mug DNA per 30 min. Subendothelial cells showed a very low activity, amounting to 10% of the value found for the endothelium. The enzyme activity was 2inhibited by the nonapeptide SQ 20881, EDTA, and the lack of Cl- in the same fashion for the two types of endothelium. The presence of another enzyme hydrolyzing His-Leu was detected in both endothelial populations. Isolated fragments of plasma membrane, however, exhibited only converting enzyme activity. It can be concluded that endothelial cells isolated from large vessels of the pulmonary and the systemic circulations have similar properties when dipeptidyl carboxypeptidase activity is measured.
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PMID:Converting enzyme activity in endothelial cells isolated from pig pulmonary artery and aorta. 40 22

Monolayer cultures of mammary gland epithelial cells were prepared from the abdominal glands of midpregnancy mice. After collagenase digestion of mammary tissue and separation by differential centrifugation, the isolated epithelial cells were cultured in Eagle's Minimal Essential Medium supplemented with 10% fetal bovine serum and insulin (6 micrograms/ml). Six days later, when the cultures were in log growth and nearly confluent, the effects of insulin and/or hydrocortisone on the rates of RNA, DNA, and protein synthesis were determined in a serum-free medium. At physiological concentrations, insulin enhanced the rates of uptake and incorporation of [3H]uridine into RNA, of [3H]thymidine into DNA, and of [3H]leucine into protein. Hydrocortisone was shown to be biphasic with regard to concentration in attenuating or augmenting insulin's effects on macromolecular synthesis.
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PMID:Actions of insulin and hydrocortisone on macromolecular synthesis in primary epithelial cell cultures from mouse mammary glands. 46 37

Effects of the calcium antagonist verapamil on the synthesis of fetal rat bone collagen and noncollagen protein were investigated in tissue culture. Protein synthesis was quantitated by measuring the incorporation of [3H]proline into collagenase-digestible (CDP) and noncollagen protein (NCP) using bacterial collagenase; [3H]proline was added for the last 2 h of culture. Verapamil (10(-5)--10(-4) M) decreased the incorporation of label into CDP and NCP after 24 h of culture; CDP formation was inhibited to a greater extent than NCP. The inhibitory response was observed in the presence and absence of unlabeled medium proline and was not associated with changes in trichloroacetic acid-extractable radioactivity. Increasing medium calcium from 1.0 to 5.0 mM did not affect the response to 10(-4) M verapamil, whereas 3.0 mM calcium abolished the response to 10(-5) M verapamil. The inhibitory effect was reversed by 48 h of control treatment subsequent to 24-h treatment with the antagonist. Verapamil did not decrease the incorporation of [3H]thymidine into DNA or [3H]uridine into RNA, nor was there any effect of the antagonist on the DNA content of cultured bones. The prostaglandin synthetase inhibitor indomethacin did not affect the response to verapamil. We conclude that a critical concentration of intracellular calcium is necessary for normal synthesis of skeletal protein in tissue culture, and that collagen may be more sensitive to changes in intracellular calcium than NCP. In addition, other ions (e.g. sodium and potassium) may also be involved in the control of skeletal protein synthesis.
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PMID:Effects of the calcium antagonist verapamil on in vitro synthesis of skeletal collagen and noncollagen protein. 48 4

The intraperitoneal administration of [3H]thymidine to adult rats resulted in the rapid appearance of label in the adipocyte fraction of collagenase digests of adipose tissue. Low-speed centrifugation followed by freezing and slicing showed the label to be uniformly distributed in the adipocyte fraction. The presence of label in DNA was confirmed by hydrolysis with deoxyribonuclease and by inhibition of incorporation with hydroxyurea. Organelle fractionation revealed that the label was predominantly in nuclei, and radioautography showed that only a few adipocyte nuclei were labeled. The label in the adipocyte fraction could not be reduced by increased collagenase digestion or by trypsin treatment. Mixing of labeled adipocytes with unlabeled stroma did not result in decrease of label and addition of labeled stroma to unlabeled adipocytes did not cause significant transfer of radioactivity. Addition of [3H]thymidine to the collagenase digestion medium of unlabeled adipose tissue resulted in more incorporation by adipocytes than by stroma, suggesting the presence of a very rapidly proliferating cell type associated more with adipocytes than with stroma. In vivo turnover studies of labeled DNA indicated that there are two components in both adipocytes and stroma, a rapidly labeled component with a half-life of only several days and another with a half-life of several months. These experiments suggest that there is a rapidly proliferating cell type in adipose tissue, closely associated with mature adipocytes, that may be an adipocyte progenitor or may have some other unknown function.
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PMID:Isotopic labeling of DNA in rat adipose tissue: evidence for proliferating cells associated with mature adipocytes. 49 48

Using a modification of the collagenase dispersion method of Dufau et al., we examined changes in DNA synthesis produced by estrogens in the interstitial cells of mice that develop malignant Leydig cell tumors after prolonged estrogen administration. Previous work in cryptorchid mice indicated that during continuous estrogen administration [3H]thymidine incorporation into DNA rises to a maximum in 3 to 4 days and then falls to approximately base levels within 2 to 3 weeks. This was confirmed both in Leydig cell concentrates of estrogen-treated mice after either injection with [3H]thymidine or incubation with [3H]thymidine in vitro. This DNA synthesis was blocked by hydroxyurea. DNA synthesis in cells of estrogen-treated BALB/c mice of the Huseby substrain, which have a high incidence of Leydig cell tumors, was 5 to 11 times that in untreated controls. Cells from estrogen-treated C3H/Bi mice, which have a low incidence of Leydig cell tumors, showed only a 2- to 3-fold increase. In the Huseby substrain the rise of DNA synthesis is a peak and subsequent recession were paralleled by a rise and fall in DNA polymerase alpha activity. DNA polymerase beta did not show this variation. In C3H/Bi mice, neither polymerase showed significant change. The evidence suggests that the early estrogen-stimulated DNA synthesis is probably replicative and is associated with increased DNA polymerase alpha activity.
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PMID:DNA synthesis and DNA polymerase activity in Leydig cells of diethylstilbestrol-stimulated mouse testes. 62 Apr 11


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