Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0850803 (anaphylaxis)
 8,092 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ro 22-3747 was orally active in two animal models of immediate hypersensitivity diseases mediated by immunoglobulin E: the rat passive cutaneous anaphylaxis test (ID50 of 0.65 mg/kg) and a model in which anaphylactic bronchospasm was studied in passively sensitized rats (ID50 of 0.022 mg/kg). In the latter model system Ro 22-3747 was also found efficacious by the aerosol route (Ro 22-3747 was 23-fold more potent than disodium cromoglycate by this route of administration). Like disodium cromoglycate (cromoglycate), Ro 22-3747 appears to act in these in vivo models by inhibition of allergic mediator release because it was a potent inhibitor of antigen-induced histamine release from passively sensitized rat peritoneal cells in vitro (IC50 values of 0.25 and 1.5 microM for Ro 22-3747 and cromoglycate, respectively) and did not exhibit end organ antagonism to histamine, serotonin or slow reacting substance of anaphylaxis. The mechanism by which Ro 22-3747 inhibits mediator release does not appear to involve inhibition of delta 5-lipoxygenase, phospholipase A2 or thromboxane synthase. Cromoglycate and Ro 22-3747 appear to have some similarities with regard to their mechanism of action, as they both exhibit a time-dependent loss of inhibitory activity when preincubated with peritoneal cells in vitro before antigen challenge. In addition, pretreatment with one prevented the subsequent inhibition of histamine release by the other. Unlike cromoglycate, however, Ro 22-3747 (10(-5) to 10(-3) M) also inhibited the release of histamine (3-59%), slow reacting substance of anaphylaxis (12-49%) and thromboxane (0-55%) from antigen-challenged (immunoglobulin G1-mediated) guinea-pig lung fragments.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Ro 22-3747: a new antiallergic agent for the treatment of immediate hypersensitivity diseases. 619 11

Rabbit peritoneal polymorphonuclear leukocytes, elicited with glycogen, metabolized added [1-14C]arachidonic acid to the 5-lipoxygenase products 5-hydroxy-6,8,11,14-eicosatetraenoic acid and 5,12-dihydroxy-6,8,10,14-eicosatetraenoic acid (leukotriene B) and the 15-lipoxygenase product 15-hydroxy-5,8,11,13-eicosatetraenoic acid. These metabolites were isolated by high pressure liquid chromatography and converted to the trimethylsilyl-ether methyl ester derivatives, and the structures were confirmed by gas chromatography-mass spectrometry. When polymorphonuclear leukocytes were preincubated with 15-HETE (16 microM), the formation of 5-hydroxy-6,8,11,14-eicosatetraenoic acid and 5,12-dihydroxy-6,8,10,14-eicostatetraenoic acid from [1-14C]arachidonic acid was strongly suppressed. The concentration required for 50% inhibition of the 5-lipoxygenase pathway in these cells was approximately 6 microM, which is comparable to the concentrations (0.20 to 1.8 microM) of 15-hydroxy-5,8,11,13-eicosatetraenoic acid produced in incubations of polymorphonuclear leukocytes with arachidonic acid alone. Recent reports indicate that slow-reacting substance of anaphylaxis (leukotriene C/D) and chemotactic substance leukotriene B are arachidonic acid metabolites formed via the 5-lipoxygenase pathway. Our observations thus suggest that 15-hydroxy-5,8,11,13-eicosatetraenoic acid can regulate the formation of these vasoactive and inflammatory mediators intracellularly.
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PMID:Inhibition of leukotriene biosynthesis by the leukocyte product 15-hydroxy-5,8,11,13-eicosatetraenoic acid. 625 63

Ten eicosanoid compounds (3, 6, 9, 11, 12, 15, 18, 21, 23, and 25), methyl (6E,8Z,11Z,14Z)-5-hydroxy-6,8,11,14-eicosatetraenoate (5-HETE, 10), leukotriene A4 (26), and (5S,6E,8E,10E,12RS,14E)-5,12-dihydroxy-6,8,10,14-eicosatetraenoic acid (5,12-diHETE, 27) were prepared and their inhibitory activities against the 5-lipoxygenase from guinea pig polymorphonuclear leukocytes (PMNL) were tested. 5,6-Methanoleukotriene A4 (18) was especially a potent and specific inhibitor of the 5-lipoxygenase without inhibiting the cyclooxygenase and the 12-lipoxygenase. Leukotriene A4, 5-HETE, and 5,12-diHETE also have inhibitory activities against the 5-lipoxygenase at micromolar concentrations, which can regulate the formation of slow-reacting substance of anaphylaxis intracellulary.
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PMID:Synthesis and 5-lipoxygenase inhibitory activities of eicosanoid compounds. 629 21

Since mouse mast tumor P-815 cells produce the slow reacting substance of anaphylaxis, their 5-lipoxygenase activity was examined by determining the conversion of arachidonic acid to 5-hydroxyeicosatetraenoic acid (HETE). Mast tumor cells from mouse ascites fluid synthesized 12-HETE as a major and 5-HETE as a minor metabolite. Once the cells were transferred to an in vitro culture system, the predominant synthesis of 12-HETE was abolished and synthesis of 5-HETE was greater than that of 12-HETE. 2-E-6 cells, obtained by cloning the tumor cells, synthesized a negligible amount of 12-HETE, but produced a large amount of 5-HETE. When the 2-E-6 cells were inoculated into mice and harvested again from the ascites fluid, their ratio of 5-HETE to 12-HETE synthesis was similar to that of normal mouse peritoneal cells; that is, 12-HETE synthesis was much greater than 5-HETE synthesis. It is concluded that the predominant synthesis of 12-HETE in mast tumor cells was derived from natural peritoneal cells, which have very high 12-lipoxygenase activity. The cloned mastocytoma, 2-E-6 cells, should be useful in investigating regulation of 5-lipoxygenase activity.
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PMID:Predominant synthesis of 5-hydroxyeicosatetraenoic acid by a cloned mastocytoma P-815 line, 2-E-6 cells. 681 Sep 46

2,3,5-Trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1,4-benzoquinone (AA861) inhibited 5-lipoxygenase of guinea pig peritoneal polymorphonuclear leukocytes (ID50, 0.8 microM). The inhibition was of competitive type. 12-Lipoxygenases and fatty acid cyclooxygenase were not affected below 10 microM. The formation of slow-reacting substance of anaphylaxis by the sensitized guinea pig lung was almost fully suppressed by the compound at 10 microM.
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PMID:2,3,5-Trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1,4-benzoquinone (AA861), a selective inhibitor of the 5-lipoxygenase reaction and the biosynthesis of slow-reacting substance of anaphylaxis. 681 8

Antiallergic effects of AL-3264 (N-[4-[4-(diphenylmethyl)-1-piperazinyl]butyl]-3-(6-methyl-3- pyridyl)acrylamide, CAS 118420-47-6) were compared with those of ketotifen, oxatomide, azelastine and tranilast in experimental animals. AL-3264 inhibited passive cutaneous anaphylaxis (PCA) in rats with an ED50 value of 6.1 mg/kg p.o. In inhibiting PCA, AL-3264 was the most potent among the antiallergic drugs examined. The anti-PCA effect of AL-3264 was long-lasting. Tolerance was not produced by repeated administration of AL-3264. AL-3264 inhibited antigen-induced bronchoconstriction in actively sensitized rats and in passively sensitized guinea pigs, with ED50 values of 14.5 and 0.44 mg/kg p.o., respectively. In the in vitro experiments, AL-3264 inhibited 5-lipoxygenase activity of guinea pig leukocytes with an IC50 value of 4.9 mumol/l, being the most potent among antiallergic drugs examined, and suppressed the antigen-induced histamine release from rat peritoneal mast cells with an IC50 value of 12.2 mumol/l. AL-3264 antagonized histamine-induced contractions in isolated guinea pig trachea with an IC50 value of 0.16 mumol/l. These results suggest that AL-3264 is an orally active, potent and long-lasting antiallergic compound which inhibits 5-lipoxygenase activity, histamine release and histamine H1 receptors at the similar concentrations.
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PMID:Antiallergic activity and mode of action of N-[4-[4-(diphenylmethyl)-1-piperazinyl]butyl]-3-(6-methyl-3- pyridyl)acrylamide in experimental animals. 768 Dec 86

Leukotrienes have been implicated in the regulation of immune responses, including inflammation and immediate hypersensitivity reactions. Here, we describe the phenotypic analysis of leukotriene-deficient mice generated by inactivation of the 5-lipoxygenase (5LO) gene. These 5LO(-/-) mice were unable to synthesize detectable levels of leukotrienes and were more resistant to lethal anaphylaxis induced by platelet-activating factor. The intensity of an acute inflammatory response induced by arachidonic acid was similar in 5LO(-/-) mice and controls. However, the response in 5LO(-/-) mice, but not in controls, could be virtually eliminated by a cyclooxygenase inhibitor. These data suggest that inflammatory responses are modulated by arachidonic acid metabolites through a variety of interconnected mechanisms. This has important implications for understanding the early events of an inflammatory response and for designing drugs for use in therapeutic intervention.
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PMID:Altered inflammatory responses in leukotriene-deficient mice. 780 34

1. Eosinophil accumulation and plasma extravasation are features of type I allergic responses. In an attempt to characterize the mediators of these responses, we have examined the local accumulation of 111In-eosinophils and leakage of 125I-human serum albumin (125I-HSA) during passive cutaneous anaphylaxis (PCA) reactions and in response to defined inflammatory mediators in the guinea-pig. Animals were passively sensitized by intradermal injection of anti-bovine gamma globulin antibody (50 microliters, 1/50 dilution). After 20-24 h, animals were injected intravenously with 111In-eosinophils and 125I-HSA for the measurement of cell accumulation and plasma leakage, respectively. 2. When injected into sensitized sites, antigen caused a dose-related increase in the accumulation of 111In-eosinophils and plasma leakage in guinea-pig skin. Time course experiments over 24 h revealed that the maximal rate of 111In-eosinophil accumulation occurred over the first 90 min, with little accumulation at later time points. Plasma leakage was completed within the first 30 min after challenge. Responses to the mast cell degranulator, compound 48/80, exhibited very similar responses to the PCA reaction. 3. Co-injection of antigen with the PAF antagonist, WEB 2086 (10(-7) mol/site) or the 5-lipoxygenase inhibitor, PF 5901 (10(-7) mol/site) did not significantly alter the accumulation of 111In-eosinophils or plasma leakage, whereas these drug doses abolished responses to exogenous PAF (10(-9) mol/site) and arachidonic acid (AA, 3 x 10(-8) mol/site), respectively. The H1 receptor antagonist chlorpheniramine (2.5 x 10(-8) mol/site) did not reduce antigen-induced 111In-eosinophil accumulation. Drug combinations were also injected with antigen into sensitized sites, but were unable to reduce "'In-eosinophil accumulation.4. These results indicate that anaphylactic eosinophil accumulation in this model involves mediators other than histamine, PAF or lipoxygenase products. This is in contrast to plasma leakage in this reaction, which can be abolished by a combination of antagonists blocking these mediators.
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PMID:Investigation of the endogenous chemoattractants involved in 111In-eosinophil accumulation in passive cutaneous anaphylactic reactions in the guinea-pig. 781 29

The aim of the study was to investigate if antigen-induced contraction of guinea pig lung parenchyma (GPLP) was an appropriate model for the study of antileukotriene drugs. Antileukotrienes have recently shown antiasthmatic effects in humans. Challenge of GPLP with a cumulatively increasing concentration of antigen evoked a graded contractile response. The antigen response could be divided into an immediate peak phase and a plateau phase of long duration. Histamine antagonism alone (mepyramine, H1, and metiamide, H2) had no effect on the response, whereas 5-lipoxygenase (5-lox) inhibitors (BAY x1005, MK-886 or BWA4C) depressed the plateau phase. When 5-lipoxygenase inhibition (BAY x1005 or MK-886) or cysteinyl-leukotriene receptor antagonism (ICI 198,615) was combined with histamine antagonism, there was a major attenuation of both components of the antigen response, leaving only a small residual response. In contrast, cyclooxygenase inhibition (diclofenac or indomethacin), antagonism of platelet-activating factor (WEB 2086) and thromboxane receptor antagonism combined with inhibition of thromboxane synthesis (BAY u3405 and CS-518) failed to inhibit the antigen response. In conclusion, cysteinyl-leukotrienes and histamine synergistically mediated the major part of the Schultz-Dale response in GPLP. The characteristics of GPLP anaphylaxis closely resembled those of antigen-challenged human bronci, supporting that antigen challenge of GPLP is a suitable model in experimental asthma research.
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PMID:Interactions between leukotrienes and histamine in the anaphylactic contraction of guinea pig lung parenchyma. 796 76

Leukotrienes constitute a class of potent biological mediators of inflammation and anaphylaxis (for reviews see refs 1 and 2). Their biosynthesis derives from 5-lipoxygenase-catalysed oxygenation of arachidonic acid in granulocytes, macrophages and mast cells. To examine the physiological importance of leukotrienes, we have disrupted the 5-lipoxygenase gene by homologous recombination in embryonic stem cells. 5-Lipoxygenase-deficient (5LX-/-) mice develop normally and are healthy. They show a selective opposition to certain inflammatory insults. Although there is no difference in their reaction to endotoxin shock, the 5LX-/- animals resist the lethal effects of shock induced by platelet-activating factor. Reaction to ear inflammation induced by phorbol ester is normal, whereas inflammation induced by arachidonic acid is markedly reduced. Contrasts were also found in two models of leukocyte chemotaxis in vivo. The phenotype of 5LX-/- mice under injurious insult identifies the role for leukotrienes in the pathophysiology of select inflammatory states.
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PMID:Role of leukotrienes revealed by targeted disruption of the 5-lipoxygenase gene. 796 51


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