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:3.2.1.31 (beta-glucuronidase)
7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Inflammatory exudates were obtained from polyester sponges which had been implanted subcutaneously in rats four days previously. This material was found to be anti-inflammatory when injected into other rats in which carrageenan pleurisy had been induced. At a dose of 600 mg kg-1 exudate inhibited the formation of pleural effusion, emigration of both neutrophils and mononuclear cells and the accumulation of beta-glucuronidase and lactic dehydrogenase. The same dose of sponge exudate did not however inhibit the increased vascular permeability induced in the rat skin or rat foot following injection of 5-hydroxytryptamine, histamine, prostaglandin E1, or bradykinin. Furthermore sponge exudate did not reduce the haemolytic complement titre of rat serum either in vivo or in vitro. The possible mechanism of anti-inflammatory action of exudate is discussed.
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PMID:Some biological and pharmacological properties of inflammatory exudates. 1 58

Ca2+, Mg2+-ionophores X537A and A23,187 (10(-7)-10(-6) M) induced the release of adenine nucleotides adenosine diphosphate (ADP, adenosine triphosphate (ATP), serotonin, beta-glucuronidase, Ca2+, and Mg2+ from washed human platelets. Enzymes present in the cytoplasm or mitochondria, and Zn2+ were not released. The rate of ATP and Ca2+ release measured by firefly lantern extract and murexide dye, respectively, was equivalent to that produced by the physiological stimulant thrombin. Ionophore-induced release of ADP, and serotonin was substantially (approximately 60%) but not completely inhibited by EGTA, EDTA, and high extracellular Mg2+, without significant reduction of Ca2+ release. The ionophore-induced release reaction is therefore partly dependent upon uptake of extracellular Ca2+ (demonstrated using 45Ca), but also occurs to a significant extent due to release into the cytoplasm of intracellular Ca2+. The ionophore-induced release reaction and aggregation of platelets could be blocked by prostaglandin E1 (PGE1) or dibutyryl cyclic AMP. The effects of PGE1, and N6, O2-dibutyryl adenosine 3':5'-cyclic monophosphoric acid (dibutyryl cAMP) were synergistically potentiated by the phosphodiesterase inhibitor theophylline. It is proposed that Ca2+ is the physiological trigger for platelet secretion and aggregation and that its intracellular effects are strongly modulated by adenosine 3':5'-cyclic monophosphoric acid (cyclic AMP).
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PMID:Human platelet secretion and aggregation induced by calcium ionophores. Inhibition by PGE1 and dibutyryl cyclic AMP. 17 96

The release of the lysosomal enzyme beta-glucuronidase from granulocytes follows incubation in vitro with complement-activated zymosan particles. Release of beta-glucuronidase is inhibited by isoproterenol, histamine, and prostaglandin E1. This in vitro model was used to study the effect of incubating a live, bivalent (A + B) influenza vaccine on the granulocyte response to the agonists described. After incubation in vitro with the live, bivalent influenza vaccine, there was a significantly impaired granulocyte reponse to all 3 agonists. The change in the response of polymorphonuclear leukocytes to isoproterenol was similar to an impairment in beta-adrenergic response found during respiratory infections in vivo. The viral-induced changes in the granulocyte response to isoproterenol may reflect similar alteration in other tissues, such as variable control of the airways and provide one explanation for the occurrence of airway dysfunction during respiratory infections.
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PMID:Impairment of isoproterenol, H2 histamine, and prostaglandin E1 response of human granulocytes after incubation in vitro with live influenza vaccines. 22 Aug 97

The pluripotent human erythroleukaemia cell line, HEL, possesses erythrocytic, megakaryocytic and macrophage-like properties. With respect to signal transduction, HEL cells have been used as a model system for platelets, but little attention has been paid to their phagocytic properties. We studied the effects of various receptor agonists on the intracellular free Ca2+ concentration ([Ca2+]i) in HEL cells. Thrombin, platelet-activating factor (PAF), ATP, UTP, prostaglandins E1 and E2 (PGE1 and PGE2), the PGE2 analogue sulprostone and the stable PGI2 analogues iloprost and cicaprost increased [Ca2+]i. ADP was less effective than ATP, and UDP was unable to increase [Ca2+]i. The increases in [Ca2+]i induced by thrombin, PAF, ATP, UTP, iloprost and cicaprost were pertussis toxin-insensitive, whereas the increases induced by PGE2 and sulprostone were completely inhibited by the toxin. The increase in [Ca2+]i induced by PGE1 was partially inhibited by pertussis toxin. PGE2 did not desensitize the increase in [Ca2+]i induced by iloprost, and vice versa. PGE1 desensitized the response to PGE2 and iloprost but not vice versa. Adrenaline potentiated the iloprost- but not the PGE2-induced rise in [Ca2+]i. The phorbol ester phorbol 12-myristate 13-acetate completely blocked the rise in [Ca2+]i induced by ATP and PGE1, whereas the increases induced by thrombin and PAF were only partially inhibited. Agonists increased [Ca2+]i through release from internal stores and sustained Ca2+ influx. Thrombin stimulated Mn2+ influx, which was blocked by Ni2+. Diltiazem, isradipine, gramicidin and 1-(beta-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl)-1H-imidazole hydrochloride (SK&F 96365) did not affect agonist-induced rises in [Ca2+]i. HEL cells contained substantial amounts of beta-glucuronidase which, however, could not be released, and they did not aggregate or generate superoxide. Our data suggest that: (1) HEL cells possess nucleotide receptors with properties similar to those of phagocytes; (2) they possess receptors for PGE2 and PGI2, and PGE1 is an agonist at both receptors; (3) agonist-induced increases in [Ca2+]i are mediated through pertussis toxin-sensitive as well as -insensitive signal transduction pathways; and (4) agonists increase [Ca2+]i by mobilization from internal stores and influx from the extracellular space through cation channels with properties similar to those of phagocytes and platelets.
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PMID:Receptor-mediated increases in cytosolic Ca2+ in the human erythroleukaemia cell line involve pertussis toxin-sensitive and -insensitive pathways. 131 May 89

Intravenous liquid halothane causes severe pulmonary edema when administered for suicide attempts. This study was carried out to elucidate the cardiopulmonary effects of intravenous liquid halothane in 14 dogs. Subjects were divided into three groups: group 1 (n = 4) was the control; group 2 (n = 5) received 7.5 mmol intravenous liquid halothane; and group 3 (n = 5) received pretreatment of continuous infusion of prostaglandin E1 at a rate of 0.02 microgram.kg-1.min-1, followed by 7.5 mmol intravenous liquid halothane. Hemodynamic values, extravascular lung water, and arterial blood gas tensions were measured for 240 min. In group 2, thromboxane B2, beta-glucuronidase, and lipid peroxides were measured in four of five dogs. In group 2, intravenous liquid halothane caused pulmonary edema associated with hypoxemia, pulmonary hypertension, and left ventricular dysfunction. In group 3, prostaglandin E1, given to reduce pulmonary vasoconstriction and left ventricular preload, aggravated hypoxemia and pulmonary hypertension and impaired left ventricular contractility, although end-diastolic left ventricular pressure was low. Thromboxane B2 increased, whereas beta-glucuronidase and lipid peroxides did not change after administration of intravenous halothane. We conclude that pulmonary edema induced by intravenous liquid halothane was due to direct pulmonary vascular damage, and that pulmonary vasoconstriction and increased left ventricular preload were not contributory causes.
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PMID:Acute pulmonary edema after intravenous liquid halothane in dogs. 144 96

The action of PGD2 and its mimetic ZK 110.841 ((5Z,13E)-(9R,11R,15S)-9-chloro-15-cyclohexyl-11,15- dihydroxy-16,17,18,19, 20-pentanor-5,13-prostadienoic acid) was compared to PGE1 in vitro on superoxide anion generation, degranulation, leukotriene (LT) B4 release and Ca++ fluxes in human polymorphonuclear leukocytes (PMN). All compounds were potent inhibitors of formyl-methionyl-leucyl-phenylalanine (FMLP)- and platelet-activating factor (PAF)-induced superoxide anion generation, beta-glucuronidase release and Ca++ influx. The PAF-induced release of LTB4 in the presence of 10 mumoles/l arachidonic acid was significantly attenuated by these prostaglandins. This inhibition of PMN function was paralleled by an increase in cellular cAMP levels. The molar potency of the prostaglandins used was comparable, although the D-type compounds appeared slightly more potent in some PMN function tests. None of the substances affected PMN activation induced by the calcium inophore calcimycin (A23187). The data demonstrate an effective inhibition of receptor-mediated (FMLP, PAF) PMN activation by PGD2 and its mimetic ZK 110.841, suggesting either an inhibitory PGD2 receptor on human PMN or action of PGD2 at the PGE receptor. PGD2 is a labile compound in vivo and is rapidly metabolized into a number of products with different biological properties. Since ZK 110.841 lacks this instability, this compound may serve as an important tool to classify PGD2-mediated reactions.
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PMID:PGD2 and its mimetic ZK 110.841 are potent inhibitors of receptor-mediated activation of human neutrophils. 164 6

The action of PGE1, PGE2, PGI2 and iloprost on superoxide anion generation, lysosomal enzyme release, and changes of Ca2+ fluxes in human polymorphonuclear leukocytes (PMN) was studied in vitro. Both PGE-type compounds were equipotent inhibitors of FMLP-and PAF-stimulated superoxide anion generation, beta-glucuronidase release (IC50 3-5 mumol/l) and Ca2+ influx while PGI2 and iloprost were ineffective at concentrations up to 10 mumol/l. These inhibitory actions of PGE1 and PGE2 were paralleled by an increase in cAMP level of the PMN while no change occurred with PGI2 and iloprost. None of the prostaglandins affected the initial intracellular Ca2+ liberation after challenge with FMLP or PAF. Preincubation of PMN with PGE1 and PGE2 but not with iloprost resulted in subsequent desensitization against a second administration of these compounds. None of the compounds affected PMN activation produced by arachidonic acid or calcimycin (A 23187). These data demonstrate that PGE-type compounds are effective inhibitors of receptor-mediated (PAF, FMLP) activation of human PMN while prostacyclins are considerably less potent. This suggests that the inhibitory prostaglandin receptor on human PMN belongs to the E-type being functionally different from the inhibitory prostaglandin receptor on human platelets. These results suggest that compounds, such as PGE1 and PGE2 might be superior to prostacyclins to prevent PMN-associated generation of reactive oxygen species and lysosomal enzyme release in situations with endogenous PMN activation, i.e. inflammatory reactions.
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PMID:Cytotoxic enzyme release and oxygen centered radical formation in human neutrophils are selectively inhibited by E-type prostaglandins but not by PGI2. 215 12

The effects of prostaglandin E1 (PGE1) and histamine on activation of superoxide (O2-) formation, exocytosis of beta-glucuronidase and aggregation in human neutrophils and HL-60 leukemic cells were studied. PGE1, histamine and impromidine, a potent H2-agonist, inhibited O2- formation in neutrophils induced by the chemotactic peptide, N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMet-Leu-Phe) with IC50 values of 0.5 microM, 8 microM and 2 microM, respectively. The full H1-agonist and weak partial H2-agonist, betahistine, was much less potent and effective than histamine. Dibutyryl cyclic AMP and forskolin mimicked the effects of histamine and PGE1 on O2- formation. The H2-antagonist, famotidine, competitively reversed histamine-induced inhibition of O2- formation with a pA2 value of 7.5. Histamine inhibited O2- formation when added prior to or after fMet-Leu-Phe. fMet-Leu-Phe-induced aggregation and release of beta-glucuronidase in neutrophils were less sensitive to inhibition by PGE1, histamine, dibutyryl cyclic AMP and forskolin than O2- formation. The inhibitor of cyclic AMP-specific phosphodiesterase, rac-4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone (Ro 20-1724), additively enhanced the inhibitory effects of histamine and PGE1 on the above cell functions. In HL-60 cells differentiated by dimethyl sulfoxide or dibutyryl cyclic AMP, histamine, impromidine and PGE1 but not betahistine inhibited fMet-Leu-Phe-induced O2- formation as well. Our data suggest that histamine inhibits activation of neutrophils and HL-60 cells via H2-receptors through activation of adenylyl cyclase and increased formation of cyclic AMP.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Histamine inhibits activation of human neutrophils and HL-60 leukemic cells via H2-receptors. 255 36

The protective effects of PGE1 on ischemia-related liver damage were evaluated in dogs. Ninety minutes warm hepatic ischemia was induced by the total clamping of hepatic inflow vasculatures with portal bypassing. The survival rate improved up to 62.5% when PGE1 was administered intravenously prior to ischemia, while no dog survived for longer than 1 week in the nontreated group. Hepatic ATP content was restored up to 80% of preischemic level 2 h after reflow in the PGE1 pretreated group, compared to 55% recovery in the nontreated group. Complete normalization of hepatic energy charge and rapid decrease of lactate were also seen in the PGE1 group. The clearance rate of intravascular lipid emulsion remained fairly normal in the PGE1 group, thereby suggesting well-preserved hepatic reticuloendothelial functions. The serum activities of beta-glucuronidase, GOT and GPT were suppressed in the PGE1-pretreated group, thereby implying a well-protected hepatic integrity. The histology revealed well-preserved hepatic architecture. The remarkable cytoprotective effect of PGE1 on hepatic ischemia shown in this study indicates that PGE1 warrants further study for protection of ischemically compromised hepatic allografts.
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PMID:Protective effect of prostaglandin E1 (PGE1) on energy metabolism and reticuloendothelial function in the ischemically damaged canine liver. 292 40

The secretory response of cytochalasin B-treated human polymorphonuclear neutrophils to the peptide chemoattractant f-Met-Leu-Phe (FMLP), the calcium ionophore A23187 and other secretagogues was measured by assaying neutrophil supernatants for the granular enzymes beta-glucuronidase and lysozyme. The dose-dependent enzyme secretion in response to 10(-8)-10(-4) M FMLP and A23187 was unaffected by pretreatment with 10-75 microM forskolin (an activator of adenylate cyclase), but inhibited by high concentrations of prostaglandins E1 and E2. The phosphodiesterase inhibitors isobutyl-methyl-xanthine (IBMX), papaverine and Ro 20-1724 dose dependently inhibited enzyme secretion from FMLP- or A23187-treated cells, and this effect was augmented in the presence of 50-75 microM forskolin. Similar results for PGE1, forskolin and forskolin/IBMX combinations were also obtained using leukotriene B4, platelet activating factor and C5a des-Arg as secretagogues. We conclude that the adenylate cyclase system of human neutrophils is activatable by forskolin, but that the regulatory effects of adenylate cyclase stimulants in these cells are greatly attenuated unless cyclic AMP-phosphodiesterases are inhibited. Thus the phosphodiesterase activity of neutrophils may be of functional importance and is relevant to the modulation of neutrophil activity in inflammation.
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PMID:Inhibition of human neutrophil degranulation by forskolin in the presence of phosphodiesterase inhibitors. 301 41


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