Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: 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)

Viable dispersed cell preparations of rat submandibular gland were obtained by a tissue-dissociation procedure using collagenase and gentle mechanical force. The cells released kallikrein-like esterase in a time- and calcium-dependent manner in response to noradrenaline (10 microM) at 30 degrees C. The net loss of kallikrein-like esterase content from the dispersed cells corresponded with the increase in kallikrein-like esterase activity in the suspending medium at all concentrations of noradrenaline. These results indicate the viability and functional integrity of this dispersed cell preparation of rat submandibular gland. alpha-Adrenoceptor agonists such as noradrenaline stimulated kallikrein-like esterase and tonin release in a dose-dependent manner, whereas the beta-adrenoceptor agonist isoprenaline and cholinoceptor agonist methacoline were both inactive. Noradrenaline-induced release of kallikrein-like esterase and tonin were completely blocked by prior addition of the alpha-adrenoceptor antagonist, phenoxybenzamine. It is concluded that the secretion of kallikrein-like esterase and tonin in rat submandibular gland is mediated only via stimulation of alpha-adrenoceptors.
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PMID:Release of kallikrein-like esterase and tonin from dispersed cells of the rat submandibular gland. 614 66

Because the liver is the major organ responsible for removal of soluble immune complexes (IC), the surface binding characteristics of preformed model IC to unstimulated mouse liver nonparenchymal cells (NPC) in suspension were studied. NPC of non-autoimmune C3H/FeJ, C3H/HeJ, A/J, DBA/2 and the autoimmune NZB/W F1 and MRL/lpr female mice of various ages were isolated by perfusion of the portal vein with collagenase followed by separation of NPC from hepatocytes with a metrizamide gradient. Thirty-five percent of NPC of all mouse strains were nonspecific esterase-positive and phagocytosed latex beads. Radiolabeled mouse IgG anti-DNP covalently cross-linked stable IC were separated by gel filtration and bound to NPC under various conditions. Marked differences were noted in maximal number of IC bound per cell between the autoimmune and non-autoimmune mouse strains: 3.3 to 4.0 X 10(5) in the non-autoimmune strains vs 0.3 to 1.4 X 10(5) molecules of IC bound per cell in the autoimmune strains at 1 to 6 mo. Insignificant differences were noted in Ka by Scatchard plot analysis (3.5 to 5.0 X 10(8) M-1) and rate of reversibility of binding as determined by dissociation of surface-bound IC with an excess of heat-aggregated gamma-globulin (T 1/2:1.5 to 2 min). These data demonstrate a decreased number of available binding sites for IC in unstimulated NPC from NZB/W F1 and MRL/lpr female mice throughout their life spans. Although the findings are consistent with saturation of binding sites of the NPC with native IC, the abnormality found in the 1-mo-old autoimmune mice (who do not have detectable autoantibodies) suggests a primary defect in FC receptor expression or an altered state of activation of NPC that may contribute to the disease process.
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PMID:Abnormal binding of soluble IgG immune complexes to hepatic nonparenchymal cells of autoimmune mice. 622 68

Various investigators have cultured murine bone marrow or peritoneal cells in vitro on glass or plastic surfaces with the ultimate aim of retrieving adherent macrophages for morphologic and functional evaluation. The removal of these adherent macrophages by conventional techniques has been consistently accompanied by low yield and significant cell damage. We report here a simple technique for culturing murine bone marrow cells in gelatin sponges (Spongostan and Gelfoam) in growth medium containing 10% fetal bovine serum and 10% L-cell conditioned medium. Viable cells were retrieved from the sponges in 10 min by digestion with collagenase. The in situ growth kinetics were similar to those found for cells cultured on plastic dishes. The recovered cells were adherent, phagocytic, positive for Fc gamma receptors, and had esterase activity.
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PMID:Cultivation of murine bone marrow macrophages in sponges: a method that permits recovery of viable cultured cells. 623 92

1. Desensitization of acetylcholine (ACh) receptors was studied at the frog neuromuscular junction under voltage clamp.2. ACh was applied directly to junctional receptors by stimulating the motor nerve with trains of impulses. End-plate currents (e.p.c.s) were used to estimate the total number of channel openings by the junctional ACh receptors, and miniature end-plate currents (m.e.p.c.s) were used to measure changes in post-synaptic sensitivity. Under the conditions of these experiments the changes in m.e.p.c. amplitudes were shown to be post-synaptic in origin and thus provided a measure of desensitization.3. When the acetylcholinesterase was inhibited with diisopropylfluorophosphate, neostigmine, or collagenase treatment to prolong the duration of the nerve-released ACh in the synaptic cleft, desensitization developed during repetitive stimulation of 1000 impulses at 5-33 impulses/sec and then recovered after the conditioning trains, with a time constant of about 25 sec.4. When the acetylcholinesterase was active so that the duration of ACh in the synaptic cleft resulting from each nerve impulse was brief (< 300 musec), desensitization developed in response to 300-500 pairs of nerve stimuli if the interval between the impulses of each pair was 25 msec or less. When the interval was 30 msec or greater, however, measurable desensitization did not occur, even if the total number of channel openings was many times greater than in the experiments with shorter intervals or inhibited esterase where desensitization readily occurred.5. The desensitization observed to pairs of impulses was enhanced by chlorpromazine and decreased when the post-synaptic membrane was depolarized, properties similar to those described previously for desensitization to bath and ionophoretic application of ACh.6. These results indicate that desensitization to nerve-released transmitter is not a simple consequence of receptor activation, is not due to blockade of the open receptor channels by ACh, and does not result from ACh binding directly to desensitized receptors with a resulting shift in the receptor population towards the desensitized state.7. We suggest that the desensitization observed to nerve-released transmitter is a two-step process with both steps initiated by ACh. In the first step ACh converts some receptors into a desensitizable state which has an apparent lifetime of less than 30 msec; in the second step ACh desensitizes the desensitizable state.
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PMID:A study of desensitization of acetylcholine receptors using nerve-released transmitter in the frog. 627 65

Whole isolated rat glomeruli (WG) were incubated with bacterial collagenase to separate epithelial cells (EC) from the cores of glomerular tufts (GC), which consisted of mesangial and endothelial cells, as demonstrated by electron microscopy. Lysates of WG, EC, and GC and of renal tubules were prepared by hypo-osmotic shock and freeze-thawing. Activities of the following acidic lysosomal hydrolases were measured: acid phosphatase, beta-glucuronidase, cathepsin-D, non-specific esterase, and aryl sulfatases A and B. The glomerular cell preparations showed activities of all studied enzymes. GC had higher activities than EC, save for nonspecific esterase. Studies of the recovery of acid phosphatase and beta-glucuronidase revealed that approximately 2/3 of the hydrolase activities present in WG was still measureable after collagenase treatment and that the bulk of this was found in the GC lysates. These findings demonstrate that the rat glomerulus and its cell components have considerable biochemical activities of acidic hydrolytic enzymes. These appear to be most prominent in the combined mesangial and endothelial cells of the GC components.
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PMID:Lysosomal enzymes in glomerular cells of the rat. 628 26

Crude bacterial collagenase was chromatographed on DEAE-cellulose to yield three peaks with proteolytic activity: an arginine esterase (DEAE-1), gelatinase (DEAE-2) and a caseinolytic activity (DEAE-3). The arginine esterase and gelatinase activity fractions were slightly contaminated with each other but neither possessed caseinolytic activity; the caseinolytic fraction was devoid of arginine esterase and gelatinase activities. In addition, crude collagenase was fractionated by ZnII-affinity chromatography to produce a gelatinase peak (ZnII peak 1), which was free from arginine esterase and caseinolytic activities. The four fractions were compared to crude collagenase in their ability to liberate rat hepatocytes by using either liver slices or a standard perfusion technique. Compared to crude collagenase (0.05-0.1% w/v), which produced 70-80% liver digestion with approximately 80% cell viability, digestion with equivalent quantities of the isolated enzymic activities was relatively poor. Gelatinase activity (ZnII peak 1) was wholly ineffective and DEAE-1 and DEAE-2 each possessed only slight digestive properties. Hepatocyte liberation by the caseinolytic activity, DEAE-3, was partially successful (30-40% digestion, 25-30% viability) but only a portion of liver tissue was digested regardless of the quantity of DEAE-3 used. However, by mixing certain fractions before perfusion two gelatinase-dependent, cell-releasing mechanisms were identified: (a) DEAE-3 with ZnII peak 1 and (b) DEAE-1 mixed with either DEAE-2 or ZnII peak 1. Each system compared creditably with the digestive properties of an equivalent activity of crude collagenase. At present we are attempting to determine any differences between hepatocytes produced by the two enzymic mechanisms.
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PMID:The role of proteolytic enzymes derived from crude bacterial collagenase in the liberation of hepatocytes from rat liver. Identification of two cell-liberating mechanisms. 631 90

Two cell lines with properties of mature macrophages have been generated by transfection with SV40 DNA mutated in the origin of replication. One line, BAM, was derived from bone marrow cells from a BALB/c mouse. The other line, BAC1, was derived from splenic adherent cells from a (BALB/c X A.CA) F1 mouse. Both lines produce lysozyme, collagenase, and esterase, bear Fc receptors, and engage in Fc-mediated phagocytosis. Both lines require colony-stimulating factor-1 for continued proliferation. In addition, they express Ia antigens, and may be induced to secrete IL 1. This technique should make possible the generation of Ia-bearing diploid macrophage lines from any strain of mouse. In addition, it may be possible to use this technique to derive monocyte lines from species in which wild-type SV40 DNA causes a lytic infection.
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PMID:The generation of macrophage-like cell lines by transfection with SV40 origin defective DNA. 631 90

Esterase release was investigated in male and female submandibular glands of 5 strains of mice (ICR/BR, ND/4BR, SW/BR, DDS/Cox and C57BL/6BR) using dispersed cells prepared by treatment with collagenase and hyaluronidase. The muscarinic-cholinergic agonist methacholine stimulated esterase release in C57BL/6BR, DDS/Cox and SW/BR females and DDS/Cox males in a dose-dependent manner, but did not stimulate esterase release in ICR/BR and ND/4BR strains of both sexes. The percentage release of esterase over control in response to methacholine in females was of the descending order: C57BL/6BR, DDS/Cox, SW/BR, ND/4BR, ICR/BR. There was a close relationship between the percentage release of esterase by methacholine and the esterase activity in homogenate of submandibular gland. The lower the esterase content in the homogenate of mouse submandibular gland, the higher the percentage release of esterase by methacholine stimulation in the dispersed cells.
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PMID:Intraspecies variation in methacholine-stimulated esterase release from mouse submandibular gland. 634 93

Certain tissues, such as the spleen, are rich sources of mononuclear phagocytes (MP); however, separating the phagocytes from tissues and removing the contaminating cells have been difficult. We report here a method for the extraction and purification of human splenic MP that employs gentle homogenization of splenic fragments with a Tenbroeck tissue homogenizer, controlled digestion with purified collagenase to free MP from splenic stroma, incubation with DNase to dissociate cell clumps and purification by countercurrent centrifugal elutriation (CCE). With homogenization and enzymatic digestion most of the splenic nonspecific-esterase-positive cells are freed into suspension as determined by morphometric analysis of 2 micron sections from plastic embedded spleen stained for alpha-naphthyl butyrate esterase (ANB). Overall cell recovery after homogenization and enzyme treatment is 56 +/- 7%; no selective cell loss occurs as determined by differential cell counts at each purification step. CCE of up to 3 X 10(9) treated spleen cells results in recovery of 63 +/- 6% of the elutriated cells and separates nearly 50% of the recovered MP into enriched fractions. These MP are morphologically intact as determined by light and electron microscopy and are actively phagocytic. Highly purified (96%) autologous splenic lymphocytes are a useful by-product of this separation technique.
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PMID:Isolation of human splenic macrophages and lymphocytes by countercurrent centrifugal elutriation. 636 Nov 49

The present study concerns the isolation, characterization, origin, and kinetics of spleen macrophages. The spleen was first perfused in situ to remove monocytes from the vascular bed and then dissected and treated with collagenase. The macrophages in the cell suspension thus obtained were characterized morphologically and cytochemically and then quantitated. The spleen cell suspension was incubated for 24 h in Leighton tubes to obtain an enriched glass-adherent population of macrophages for characterization and [3H]thymidine-labeling studies. Almost all of the adhering macrophages were esterase positive, had Fc and C3b receptors, and ingested EIgG and opsonized bacteria. In vitro labeling with [3H]thymidine showed that approximately 5% of the mononuclear phagocytes in the spleen synthesize DNA and must be considered to be dividing cells. The course of the number of labeled monocytes and macrophages after a single injection of [3H]thymidine indicates migration of monocytes into the spleen, where they become macrophages. Calculation of the influx of monocytes into the spleen and of the local production of macrophages by DNA-synthesizing mononuclear phagocytes showed that under steady-state conditions, 55% of the population of spleen macrophages is supplied by monocyte influx and 45% by local production. This means that there is a dual origin of spleen macrophages. The mean turnover time calculated with the value for the efflux of spleen macrophages is 6.0 d.
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PMID:Dual origin of mouse spleen macrophages. 649


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