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)

Serum collagenase was significantly elevated in stage II, but not stage I sarcoidosis, in contrast to elevation of serum angiotensin-converting enzyme in stages I and II. Neither serum collagenase nor angiotensin-converting enzyme was elevated in active tuberculosis. Elevated serum collagenase and angiotensin-converting enzyme levels were decreased with steroid therapy. Serum collagenase and angiotensin-converting enzyme were significantly correlated but did not vary identically. Collagenase was not elevated in lymph nodes in sarcoidosis, in contrast to marked elevation of angiotensin-converting enzyme. The results suggest that serum angiotensin-converting enzyme is a more sensitive index of sarcoidosis activity than serum collagenase, which may have an ancillary role in assessment of the disease.
Am J Clin Pathol 1978 Sep
PMID:Serum and lymph-node collagenase in sarcoidosis. Comparison with angiotensin-converting enzyme. 21 44

An operational criterion for the identification and isolation of epithelial-like (E) cells, based on their ability to cover and protect a collagen gel from the action of collagenase, has been developed. The E cells isolated by this collagenase-separation technique (CST) exhibited the ultrastructural features, including desmosomes and abundant tonofilaments, that are considered characteristic of this cell type. Unlike confluent cultures of fibroblast-like (F) cells, E cells were not found to have large external transformation-sensitive (LETS) protein on their surface membranes. The CST provides a nondestructive and efficient means of identifying and isolating E cells from mixed populations.
In Vitro 1978 Sep
PMID:Isolation and identification of epithelial-like cells in culture by a collagenase-separation technique. 21 90

The role of cyclic AMP in the regulation of aldosterone production by adrenocorticotropic hormone (ACTH), angiotensin II (A II), potassium, and serotonin was examined in collagenase-dispersed adrenal glomerulosa cells. The ability of 8-bromo cyclic AMP and choleragen to stimulate maximum aldosterone production indicated that cyclic AMP could act as second messenger for certain of the aldosterone-stimulating factors. The actions of ACTH and choleragen on aldosterone and cyclic AMP production were correlated in dog and rat cells, and a similar relation was seen during stimulation of rat cells by serotonin. In contrast, A II and potassium did not cause changes in cyclic AMP formation while stimulating aldosterone production. Intracellular and receptor-bound cyclic AMP were increased 3-fold by 10(-7) M ACTH but not by A II. Addition of a phosphodiesterase inhibitor increased the magnitude of the cyclic AMP response to ACTH but did not change the lack of stimulation by A II or potassium. In dog cells, the effects of A II and potassium on aldosterone production were partially additive to those of ACTH, choleragen, and 8-bromo cyclic AMP. In contrast, no additivity was observed between A II and potassium, or between combinations of the cyclic AMP-dependent stimuli. These results indicate that the actions of ACTH on aldosterone secretion are mediated by cyclic AMP formation, whereas A II and potassium stimulate aldosterone production through an independent mechanism. The lack of additivity between steroid responses to A II and potassium suggests that these factors could share a common mode of action on steroidogenesis in zona glomerulosa cells.
J Biol Chem 1979 Sep 10
PMID:The role of cyclic AMP in aldosterone production by isolated zona glomerulosa cells. 22 59

1. The uptake of 125I-labelled high density lipoproteins (HDL) in various organs of the rat was determined after an intravenous injection. The uptake of 125I-labelled polyvinylpyrrolidone in the same organs was determined in order to assess uptake by fluid endocytosis. The uptake/organ was highest for the liver. The adrenals showed the highest uptake/unit weight of the organs studied. The liver, the kidneys and the spleen showed comparable values for uptake/g of tissue. The uptake of 125I-labelled HDL exceeded by far that of 125I-labelled polyvinylpyrrolidone in the liver, the kidneys, the spleen and the adrenals, indicating that the uptake of 125I-labelled HDL was mediated by adsorptive endocytosis. 2. The in vivo uptake of 125I-labelled HDL was determined in purified hepatocytes and non-parenchymal cells prepared by collagenase perfusion of livers from animals after intravenous injections of 125I-labelled HDL. When expressed per cell, the hepatocytes and the non-parenchymal liver cells took up about the same amount of 125I-labelled HDL. 3. The in vitro uptake and degradation of 125I-labelled HDL in isolated rat hepatocytes was studied. The uptake at increasing concentrations of 125I-labelled HDL was saturable indicating uptake mediated through binding sites. 125I-labelled HDL were easily degraded by contaminating proteases from the perfusate. 4. Subcellular fractionation by isopycnic centrifugation indicated that the accumulation of 125I-labelled HDL did not take place in the lysosomes, but rather on the plasma membrane and possibly in the endosomes (phagosomes). 5. 125I-labelled HDL were internalized into the cells and degraded in the lysosomes. Leupetin and chloroquine, inhibitors of the lysosomal function effectively inhibited the formation of 125I-labelled acid-soluble radioactivity by the cells. Chloroquine, but not the protease inhibitor leupeptin, reduced the hydrolysis of the cholesteryl ester moiety of HDL.
Biochim Biophys Acta 1979 Sep 28
PMID:Uptake and degradation of 125I-labelled high density lipoproteins in rat liver cells in vivo and in vitro. 22 59

A simple method to determine adenylate cyclase activity in isolated single nephron segments is described. Segments of the proximal convoluted tubule or the cortical collecting tubule were isolated from rabbit kidney slices pretreated with collagenase. After the tubule membranes were made permeable by adding hypotonic medium and freezing-thawing, each sample was incubated at 30 degrees C for 30 min in a medium containing ATP and theophylline. Generated cAMP was succinylated and served for radioimmunoassay. Addition of the incubation medium did not interfere the radioimmunoassay. Recovery of added cAMP was 96%. In the proximal convoluted tubule, either 8 mM NaF or 1 U/ml parathyroid hormone (PTH) markedly stimulated adenylate cyclase activity, but 1 mU/ml arginine vasopressin (AVP) did not. By contrast, in the cortical collecting tubule, either 8 mM NaF or 1 mU/ML AVP markedly stimulated adenylate cyclase activity, but 1 U/ml PTH did not. These data imply that this method is sensitive enough to detect either specific or nonspecific response of adenylate cyclase activity in single nephron segments.
Tohoku J Exp Med 1979 Sep
PMID:A simple method to determine adenylate cyclase activity in isolated single nephron segments by radioimmunoassay for succinyl adenosine 3',5'-cyclic monophosphate. 22 39

An enzymatic procedure for the isolation of metabolically active tumour cells from human renal cell carcinoma is described. The cells were suspended by a multistep incubation procedure of the tissue in the presence of collagenase (10 mg enzyme/g tumour wet weight) dissolved in a calcium-free buffer solution. About 90% of the isolated tumour cells were viable, as judged by routine trypan blue staining. Electron microscopic examination revealed tumour cells in various stages of dedifferentiation. The cells had retained their capability of protein synthesis. In short term experiments the effects of 17 beta-oestradiol and progesterone on the incorporation of [U - C] L-leucine into cellular proteins was studied; Progesterone was found to exhibit a slight tumour antianabolic or catabolic action. A 17 beta-oestradiol-dependent modulation of the rates of protein synthesis was not observed.
Urologe A 1979 Sep
PMID:[Viable cells from human renal cell carcinoma: isolation procedure and analysis of hormone sensitivity (author's transl)]. 22 52

Free polyribosomes and polyribosomes bound to endoplasmic membranes were isolated from 10-day-old chick embryos by differential centrifugation. The tightly and loosely bound polyribosomal fractions were isolated from the membrane-bound polyribosomes using 0,5 M KCl. The synthesis of collagen and non-collagen proteins on the polyribosomes were studied in a homologous cell-free system. It was shown that the polyribosomes tightly bound to the membranes possess a lower protein-synthesizing activity as compared to free and loosely bound polyribosomes. The amount of bacterial collagenase-cleaved polypeptides in the protein product synthesized on the polyribosomes tightly and loosely bound to the memranes and on free polyribosomes is 31, 23 and 9%, respectively. The data obtained suggest that the loosely bound polyribosomes are actively involved in collagen synthesis and that this fraction is not a contamination of free polyribosomes in the preparations of totally bound polyribosomes. The role of tightly and loosely bound polyribosomes in the formation of the membrane polyribosomal complex is discussed.
Biokhimiia 1979 Sep
PMID:[Biosynthesis of collagen and other proteins on tightly and loosely bound polyribosomes from chick embryos]. 22 74

1. The kinetics of tubocurarine inhibition were studied at the post-synaptic membrane of frog skeletal muscle fibres. Acetylcholine (ACh) and (+)-tubocurarine were ionophoresed from twin-barrel micropipettes, and the membrane potential of the muscle fibre was recorded intracellularly. Tubocurarine-receptor binding was measured by decreases in the response to identical pulses of ACh. 2. The responses to both ACh and tubocurarine had brief latencies and reached their maxima rapidly. It is suggested that under these conditions the kinetics of tubocurarine action are not slowed by diffusion in the space outside the synaptic cleft. 3. After a pulse of tubocurarine, recovery from inhibition proceeds along a roughly exponential time course with a rate constant, 1/tau off approximately equal to 0.5 sec-1. This rate constant does not depend on the maximal level of inhibition and varies only slightly with temperature (Q10 = 1.25). 4. After a sudden maintained increase in tubocurarine release, the ACh responses decrease and eventually reach a new steady-state level. Inhibition develops exponentially with time and the apparent rate constant, 1/tau on, is greater than 1/tau off. When the steady-state inhibition reduces the ACh response to 1/n of its original level, the data are summarized by the relation, 1/tau on = n(1/tau off). 5. When the ACh sensitivity is reduced with cobra toxin, both 1/tau on and 1/tau off increase. Thus, the kinetics of tubocurarine inhibition depend on the density of ACh receptors in the synaptic cleft. 6. After treatment with collagenase, part of the nerve terminal is displaced and the post-synaptic membrane is exposed directly to the external solution. Under these circumstances, 1/tau off increases more than tenfold. 7. Bath-applied tubocurarine competitively inhibits the responses to brief ionophoretic ACh pulses with an apparent equilibrium dissociation constant, K = 0.5 microM. 8. In denervated frog muscle fibres, extrasynaptic receptors have a lower apparent affinity for tubocurarine. After a pulse of tubocurarine, inhibition decays tenfold more rapidly at these extrasynaptic sites than at the synapse. 9. It is suggested that each tubocurarine molecule binds repeatedly to several ACh receptors before escaping from the synaptic from the synaptic cleft and that the probability of this repetitive binding is enhanced because the nerve terminal presents a physical barrier to diffusion out of the cleft. Consequently, the receptor transiently buffer the concentration of tubocurarine in the cleft, and the macroscopic kinetics of inhibition are much slower than the molecular binding rates for tubocurarine.
J Physiol 1979 Sep
PMID:The kinetics of tubocurarine action and restricted diffusion within the synaptic cleft. 22 14

The synovial fluid (SF) of RA patients contains large amounts of PMN which are well equipped with neutral enzymes to degrade articular cartilage: elastase and cathepsin G, which both destroy proteoglycans and native collagen, as well as 2 types of collagenoases. Indirect evidence suggests that PMN might be important in the destruction of RA articular cartilage. In 19 SF of RA patients no free elastase or collagenase was found. Using immune histochemical methods, we observed that PMN and macrophages of SF contain both elastase and alpha 1-anti-trypsin and alpha 2-macroglobulin. Peripheral PMN - but not monocytes - contain elastase, however both types of cells lack alpha 1-antitrypsin and alpha 2-macroglobulin. Elastase is demonstratable in the superficial layer of pannus free RA articular cartilage. These findings suggest that neutral proteinases from PMN in RA SF are generally neutralized by physiologic inhibitors and removed by phagocytes. The enzyme-inhibitor interaction might be bypassed during "frustrated phagocytosis" so that enzymes like PMN elastase can damage RA articular cartilage.
Bull Schweiz Akad Med Wiss 1979 Sep
PMID:[Chronic polyarthritis: role of polymorphonuclear leukocytes in the destruction of pannus-free articular cartilage]. 23 68

Connective tissue destruction is a major characteristic of chornic rheumatoid arthritis (RA). This process is accompanied by local cellular and humoral inflammatory reactions. Long-term cultures of adherent synovial cells (ASC) from patients with RA produce large amounts of collagenase and prostaglandin (PGE2), two substances that play a role in the degradation of joint structures. Lvels of collagenase and PGE2 can be stimulated (up to several hundred-fold) with a soluble factor (MCF) from cultured peripheral blood mononuclear cells (MW approximately 14,000). The monocyte-macrophages alone produce MCF but can be stimulated directly with Fc fragments of immunoglobulin or concanavalin A to increase MCF production. Addition of T lymphocytes in the presence of lectin or antigen significantly enhances the production of MCF. MCF affects other biological processes in synovial cells such as the rate of collagen synthesis, cell proliferation and sensitivity to PGE2 as well as collagen itself can further modulate collagenase release by the synovial cells and function in an amplificative loop. The understanding of these interactions between cells, mediator-effector substances and connective tissue substrates may provide a basis for devising more rational approaches to therapy of the destructive lesions which characterize RA.
Bull Schweiz Akad Med Wiss 1979 Sep
PMID:Collagenase and prostaglandin in connective tissue destruction: cell-cell and humoral interactions. 23 69


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