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At least 721 records · Page 40Linked to original sources
PubMed2006

The Yersinia enterocolitica invasin protein promotes major histocompatibility complex class I- and class II-restricted T-cell responses.

Yersinia enterocolitica invasin (Inv) protein confers internalization into and expression of proinflammatory cytokines by host cells. Both events require binding of Inv to beta1 integrins, which initiates signaling cascades including activation of focal adhesion complexes, Rac1, mitogen-activated protein kinase, and NF-kappaB. Here we tested whether Inv might be suitable as a delivery molecule and adjuvant if used as a component of a vaccine. For this purpose, hybrid proteins composed of Inv and ovalbumin (OVA) were prepared, applied as a coating to microparticles, and used for vaccination. Fusion of OVA to Inv did not significantly disturb the ability of Inv to promote host cell binding, internalization, and interleukin-8 (IL-8) secretion when applied as a coating to microparticles. The microparticles were used for vaccination of mice adoptively transferred with OVA-specific T cells from OT-1 or DO11.10 mice. Administration of OVA-Inv-coated microparticles induced OVA-specific T-cell responses. OVA-specific CD4 T cells produced both gamma interferon (IFN-gamma) and IL-4 as determined by enzyme-linked immunosorbent assay. Likewise, pronounced OVA-specific CD8 T-cell responses associated with IFN-gamma production were observed. Together, these results suggest that Inv might be an attractive tool in vaccination as it confers both host cell uptake and adjuvant activity by engagement of beta1 integrins of host cells, which leads to CD4 as well as CD8 T-cell responses.

Adhesins, Bacterial↗
PubMed2004

Basic advances and new avenues in therapy of spinal cord injury.

The prospects for successful clinical trials of neuroprotective and neurorestorative interventions for patients with acute and chronic myelopathies depend on preclinical animal models of injury and repair that reflect the human condition. Remarkable progress continues in the attempt to promote connections between the brain and the sensory and motor neurons below a spinal cord lesion. Recent experiments demonstrate the potential for biological therapies to regenerate or remyelinate axons and to incorporate new neural cells into the milieu of a traumatic spinal cord injury. The computational flexibility and plasticity of the sensorimotor systems of the brain, spinal cord, and motor unit make functional use of new circuitry feasible in patients. To incorporate residual and new pathways, neural repair strategies must be coupled to rehabilitation therapies that drive activity-dependent plasticity for walking, for reaching and grasping, and for bowel and bladder control. Prevention of pain and dysautonomia are also clinical targets. Research aims to define the temporal windows of opportunity for interventions, test the safety and efficacy of delivery systems of agents and cells, and provide a better understanding of the cascades of gene expression and cell interactions both acutely and chronically after injury. These bench-to-bedside studies are defining the neurobiology of spinal cord injury rehabilitation.

Animals↗
PubMed2003

Metabolic acidosis stimulates RANKL RNA expression in bone through a cyclo-oxygenase-dependent mechanism.

UNLABELLED: Metabolic acidosis inhibits osteoblastic bone formation and stimulates osteoclastic resorption. To determine whether acidosis alters expression of RNA for the osteoclastic differentiation factor RANKL, mouse calvariae were incubated in neutral or physiologically acidic media. Acidosis resulted in a significant cyclo-oxygenase-dependent increase in RANKL RNA levels, which would be expected to induce the associated increase in bone resorption. INTRODUCTION: Metabolic acidosis increases net calcium efflux from bone, initially through physicochemical mechanisms and later through predominantly cell-mediated mechanisms. Acidosis decreases osteoblastic bone formation and increases osteoclastic resorption. The growth and maturation of osteoclasts, derived from hematopoietic precursors in the monocyte/macrophage lineage, are dependent on the interplay of a number of factors. Commitment of pre-osteoclasts to osteoclasts is induced by the interaction of the osteoclastic cell-surface receptor RANK with a ligand expressed by osteoblasts, RANKL. The RANK/RANKL interaction not only initiates a differentiation cascade that culminates in mature bone-resorbing osteoclasts but also increases osteoclastic resorptive capacity and survival. METHODS: To test the hypothesis that metabolic acidosis increases expression of RANKL, we cultured neonatal mouse calvariae in acidic (initial medium pH approximately 7.1 and [HCO3-] approximately 11 mM) or neutral (initial medium pH approximately 7.5 and [HCO3-] approximately 25 mM) medium for 24 and 48 h. We determined the relative expression of RANKL RNA by reverse transcriptase-polymerase chain reaction (RT-PCR) and quantitated the expression by Northern analysis. RESULTS: In this model of metabolic acidosis, there was significantly increased expression of RANKL RNA at both 24 (2-fold) and 48 h (5-fold) compared with respective controls. Net calcium efflux from bone was also increased in acidic medium compared with control medium. At 48 h, net calcium efflux correlated directly with RANKL expression (r = 0.77, n = 15, p < 0.001). Inhibition of prostaglandin synthesis with indomethacin blocked the acid-induced increase in RANKL RNA as well as the increased calcium efflux. CONCLUSIONS: Metabolic acidosis induces osteoblastic prostaglandin synthesis, followed by autocrine or paracrine induction of RANKL. This increase in RANKL would be expected to augment osteoclastic bone resorption and help explain the increase in cell-mediated net calcium efflux.

Acidosis↗
PubMed2005

Evaluation of quantum-cascade lasers as local oscillators for infrared heterodyne spectroscopy.

We report experiments evaluating the feasibility of quantum-cascade lasers (QCLs) at mid-infrared wavelengths for use as local oscillators (LOs) in a heterodyne receiver. Performance tests with continuous-wave (cw) lasers around 9.6 and 9.2 microm were carried out investigating optical output power, laser linewidth, and tunability. A direct comparison with a CO2 gas laser LO is presented as well. The achieved system sensitivity in a heterodyne spectrometer of only a factor of 2 above the quantum limit together with the measured linewidth of less than 1.5 MHz shows that QCLs are suitable laser sources for heterodyne spectroscopy with sufficient output power to replace gas lasers as LOs even in high-sensitivity astronomical heterodyne receivers. In addition, our experiments show that the tunability of the lasers can be greatly enhanced by use of an external cavity.

Journal Article↗
PubMed2004

Interaction and association analysis of a type 1 diabetes susceptibility locus on chromosome 5q11-q13 and the 7q32 chromosomal region in Scandinavian families.

We have previously reported suggestive linkage to chromosome 5p13-q13 in type 1 diabetic families. ISL1, a transcription factor involved in pancreas development, maps to this region. Sequencing of the ISL1 gene in patients and control subjects identified seven single nucleotide polymorphisms (SNPs) and one microsatellite in noncoding regions. Four haplotypes formed by six of these SNPs and one microsatellite were associated with type 1 diabetes in Swedish families (P < 0.04). To identify possible interactions with the 5q11-q13 region, we applied pathway-restricted linkage analysis by analyzing for effects from regions encoding other transcription factors that are active during pancreas development and maintenance of insulin production. Linkage analysis allowing for interaction between 5q11-q13 and 7q32 resulted in an increase of logarithm of odds from 2.2 to 5.3. This increase was estimated to correspond to a P value <0.0016 using permutation. The transcription factor PAX4 is located at 7q32 and participates downstream of ISL1 in the transcription factor cascade critical to beta-cell development. Association with type 1 diabetes was also observed using the transmission disequilibrium test for two haplotypes at the PAX4 locus (P < 0.05). We conclude that pathway-restricted linkage analysis assists in the identification of possible gene-gene interactions and that 5q11-q13 and 7q32 together constitute a significant susceptibility factor for type 1 diabetes.

Chromosome Mapping↗
PubMed2004

[Influence of 2-aryl-3-halogen/3-hydroxy-1,4-naphthoquinones with salicylic and cinnamic acid partial structures on the arachidonic acid cascade].

Searching for more potent 5-lipoxygenase (LO) inhibitors one tert-butyl group of the selective 5-LO-inhibitor 2-(3,5-di-tert-butyl-4-hydroxyphenyl)-3-hydroxy-1,4-naphthoquinone (1) was substituted by polar functions (-CHO, -COOH, -CH=CH-COOR, -CH2-CH2-COOR). At the same time the 5-LO selectivity of the new compounds within the arachidonic acid cascade was investigated. For this 12-LO- and COX-1-assays with activated human platelets were used. Screening the test compounds new selective 5-LO-inhibitors (4, 9 and 16) and a COX-1-inhibitor (10) as well as dual 5-LO/COX-1- (23) and 12-LO/COX-1- (12) inhibiting compounds were found. Obviously in this class of compounds 5-LO and 12-LO inhibition are mutually excluded for a structural reason. In addition to the well known 3-chloro- (19) and 3-bromo- (20) analogues of 1 the 3-fluoro- (22), 3-iodo- (23) and the 3-carbonitrile- (24) derivatives were synthesized. All 3-halogen compounds, except 23 and the nitrile, are potent non selective inhibitors of all three enzymes. Causative for this unselectivity is the inhibition of the arachidonic acid release by inhibition of the cytosolic phospholipase A2 (cPLA2) with the exception of 24.

Arachidonic Acid↗
PubMed1997

[Systemic inflammatory reactions to extracorporeal therapy measures (I): Hemodialysis and hemofiltration].

Hemodialysis and hemofiltration (intermittent or continuous) are the most frequently applied extracorporeal treatment strategies, enabling survival of patients with acute or chronic renal failure. To a various degree on the other hand they induce an undesirable inflammatory response summarized as bioincompatibility. Apart from the quality of the dialysate the composition of the dialytic membrane itself appears to be of very great importance in triggering this inflammatory process. The main humoral and cellular mechanisms underlying this inflammatory response are the activation of complement cascade, the activation of blood cells, the release of cytokines and the induction of nitric oxide synthesis. Various laboratory tests have confirmed a lower degree of inflammatory response on using synthetic membranes in comparison with cuprophane membranes. The importance of these differences in the treatment of dialysis patients with respecto to intradialytic complications and long-term morbidity and mortality, is, however, still a matter of debate. The results of clinical investigations to date are conflicting and have not yet clearly proven, whether implementation of synthetic membranes is of any benefit to dialysis patients or not. Apart from the cost factor there is no argument in favour of using cuprophane membranes.

Complement Activation↗
PubMed1981

Cascade immunoelectrophoresis: combined electrophoretic and solid-phase processing of immunoreactive protein by zonal immobilization.

A new approach to immunochemical analysis of complex mixtures of proteins has been devised through development of a system for (1) sequentially absorbing, desorbing, and cascading antibodies in a profile indicative of both the quantity and electrophoretic characteristics of the antigen, and (2) for carrying out multiple tests of antigenic determinants at sub-picomole levels regardless of the solubility or precipitin forming characteristics of the immunoreactive protein. The procedure employs zonal immobilization in which a novel, aldehyde-rich gel (glyoxyl agarose) is used interchangeably as an inert support for electrophoresis and as an immobilizing matrix to fix the protein for analysis by solid-phase techniques. Proteins may be separated on the gel as with ordinary agarose, and then driven to combine covalently with the gel upon exposure to NaCNBH3. After removing NaCNBH3, the distribution of specified antigens is then established by exposing the gel to antibody an profiling the pattern of antibody uptake by a cross-electrophoretic technique in which the absorbed antibody is (1) desorbed with dodecyl sulfate, then (2) transferred through a gel containing potassium ion to halt migration of the detergent, and (3) displayed by immunoprecipitation with anti-IgG antibodies. To cascade the process further, the IgG may be immobilized and used as a surrogate antigen to bind additional antibody protein. In addition to enhancing sensitivity, the cross-electrophoretic measurement of uptake of antibody by immobilized antigen eliminates dependence on direct immunoprecipitation of the antigen, and may accordingly be of particular advantage with non-precipitin forming antigens and monoclonal antibodies.

Aldehydes↗
PubMed2004

Silencing of hydroperoxide lyase and allene oxide synthase reveals substrate and defense signaling crosstalk in Nicotiana attenuata.

The fatty acid hydroperoxide (HP) substrates required for the biosynthesis of jasmonic acid (JA) and green leaf volatiles (GLVs) are supplied by separate lipoxygenases (LOX). We silenced the expression of two genes downstream of the LOX: allene oxide synthase (AOS) and HP lyase (HPL) by antisense expression of endogenous genes (NaAOS, NaHPL) in Nicotiana attenuata, in which the biosynthesis of JA is amplified by herbivore-specific elicitors. We report that these elicitors also amplify wound-induced GLV releases, but suppress the wound-induced increase of NaHPL transcripts, suggesting that substrate flux controls GLV biosynthesis. As expected, silencing of NaHPL and NaAOS reduced GLV release and JA accumulation, respectively. Surprisingly, HPL- and AOS-silenced plants had enhanced JA and GLV responses, suggesting substrate 'crosstalk' between these two oxylipin cascades. Plants with depleted GLVs (as-hpl) were less attractive than wild type (WT) or empty vector control plants in choice-tests with native lepidopteran herbivores. In feeding trials, Manduca sexta larvae developed slower on as-hpl plants. The reduced larval consumption and performance, which was not caused by increases in defense responses in as-hpl plants, could be restored to WT levels by the addition of synthetic GLVs, demonstrating that GLVs function as feeding stimulants. Gene expression profiling by cDNA microarray analysis and characterization of several induced defenses in herbivore-elicited as-hpl and as-aos plants revealed differential involvement of JA and GLVs in defense signaling. Elicitation of volatile terpenoids (an indirect defense) requires JA signaling, where as trypsin protease inhibitor elicitation (a direct defense) requires both functional JA and GLV cascades.

Aldehyde-Lyases↗
PubMed2006

A CsgD-independent pathway for cellulose production and biofilm formation in Escherichia coli.

Bacterial growth on a surface often involves the production of a polysaccharide-rich extracellular matrix that provides structural support for the formation of biofilm communities. In Salmonella, cellulose is one of the major constituents of the biofilm matrix. Its production is regulated by CsgD and the diguanylate cyclase AdrA that activates cellulose synthesis at a posttranscriptional level. Here, we studied a collection of Escherichia coli isolates, and we found that the ability to produce cellulose is a common trait shared by more than 50% of the tested strains. We investigated the genetic determinants of cellulose production and its role in biofilm formation in the commensal strain E. coli 1094. By contrast with the Salmonella cellulose regulatory cascade, neither CsgD nor AdrA is required in E. coli 1094 to regulate cellulose production. In this strain, an alternative cellulose regulatory pathway is used, which involves the GGDEF domain protein, YedQ. Although AdrA(1094) is functional, it is weakly expressed in E. coli 1094 compared to YedQ, which constitutively activates cellulose production under all tested environmental conditions. The study of cellulose regulation in several other E. coli isolates showed that, besides the CsgD/AdrA regulatory pathway, both CsgD-independent/YedQ-dependent and CsgD-independent/YedQ-independent pathways are found, indicating that alternative cellulose pathways are common in E. coli and possibly in other cellulose-producing Enterobacteriaceae.

Amino Acid Motifs↗
PubMed2004

Multimeric tyrosine sulfate acts as an endothelial cell protectant and prevents complement activation in xenotransplantation models.

BACKGROUND: Activation of endothelial cells (EC) in xenotransplantation is mostly induced through binding of antibodies (Ab) and activation of the complement system. Activated EC lose their heparan sulfate proteoglycan (HSPG) layer and exhibit a procoagulant and pro-inflammatory cell surface. We have recently shown that the semi-synthetic proteoglycan analog dextran sulfate (DXS, MW 5000) blocks activation of the complement cascade and acts as an EC-protectant both in vitro and in vivo. However, DXS is a strong anticoagulant and systemic use of this substance in a clinical setting might therefore be compromised. It was the aim of this study to investigate a novel, fully synthetic EC-protectant with reduced inhibition of the coagulation system. METHOD: By screening with standard complement (CH50) and coagulation assays (activated partial thromboplastin time, aPTT), a conjugate of tyrosine sulfate to a polymer-backbone (sTyr-PAA) was identified as a candidate EC-protectant. The pathway-specificity of complement inhibition by sTyr-PAA was tested in hemolytic assays. To further characterize the substance, the effects of sTyr-PAA and DXS on complement deposition on pig cells were compared by flow cytometry and cytotoxicity assays. Using fluorescein-labeled sTyr-PAA (sTyr-PAA-Fluo), the binding of sTyr-PAA to cell surfaces was also investigated. RESULTS: Of all tested compounds, sTyr-PAA was the most effective substance in inhibiting all three pathways of complement activation. Its capacity to inhibit the coagulation cascade was significantly reduced as compared with DXS. sTyr-PAA also dose-dependently inhibited deposition of human complement on pig cells and this inhibition correlated with the binding of sTyr-PAA to the cells. Moreover, we were able to demonstrate that sTyr-PAA binds preferentially and dose-dependently to damaged EC. CONCLUSIONS: We could show that sTyr-PAA acts as an EC-protectant by binding to the cells and protecting them from complement-mediated damage. It has less effect on the coagulation system than DXS and may therefore have potential for in vivo application.

Adult↗
PubMed1988

Effects of lipoxygenase inhibitors on the arachidonic acid cascade in the rabbit cornea after injury.

A cryogenic lesion in the rabbit cornea that promotes the formation of arachidonic acid metabolites was used as a model to test the action of two new lipoxygenase inhibitors, TEI-8005 and TEI-8006. The action of these two inhibitors was compared with that of CBS-113A, a new dual inhibitor of cyclooxygenase and lipoxygenase reactions, and with that of nordihydroguaiaretic acid (NDGA), a monooxygenase inhibitor and antioxidant. Injured corneas were incubated for 1 h at 36 degrees with 1-14C-arachidonic acid. Inhibitors at concentrations of 1, 10 and 100 uM were added 10 minutes prior to the addition of arachidonic acid. TEI-8006 inhibited 5-hydroxyeicosatetraenoic acid (HETE) at 10 uM, and both 5- and 12-HETE at 100 uM. At 100 uM, CBS-113A also had the same effect, while TEI-8005 at 100 uM induced a more selective inhibition of 5-lipoxygenase. NDGA was the most potent inhibitor of lipoxygenase reactions, but was not selective. Prostaglandins were also affected differentially by the inhibitors. TEI-8006 and NDGA partially inhibited cyclooxygenase products at all concentrations, and CBS-113A produced inhibition at 10 and 100 uM. TEI-8005 did not affect the total cyclooxygenase products, but selectively inhibited thromboxane B2 and increased prostacyclin production at 100 uM. The effects of these inhibitors may be of value in understanding the mechanisms involved in corneal inflammation.

Animals↗
PubMed2002

Lacrosse Helmet Designs and the Effects of Impact Forces.

OBJECTIVE: To examine the effects of repetitive impact forces on lacrosse helmets and increase awareness of helmet safety standards about reconditioning and recertification practices. DESIGN AND SETTING: The independent variables for this study consisted of 4 lacrosse helmets of various design: 2 contemporary helmets (Sport Helmets Cascade and Cascade Air) and 2 traditional helmets (Sport Helmets Ultralite and Bacharach Ultralite). The dependent variable was attenuation of impact forces as measured by the Gadd Severity Index (GSI). Helmets were tested at an independent testing facility certified by the National Athletic Equipment Reconditioners Association. MEASUREMENTS: Helmets were raised to 152 cm and released onto an anvil padded with a 1.27-cm rubber modular elastomer programmer. Ten treatments to a front (FD) and right rear boss drop site (RD) were performed. A triaxial accelerometer within the head form measured impact force. Peak acceleration data were integrated into the GSI. We performed a 1-way analysis of variance and calculated descriptive statistics and the Tukey post hoc test. RESULTS: A statistically significant difference was seen in FD GSI score (F(3,36) = 9.680, P <.05) and in the RD GSI score (F(3,36) = 28.140, P <.05) between helmet types. Mean GSI scores were 1166.1, 1117.6, 857, and 1222.8 for the FD and 974.5, 1022.1, 1376.3, and 1496.5 for the RD for Sport Helmets Cascade, Cascade Air, Ultralite, and Bacharach Ultralite, respectively. With repetitive drops, GSI scores increased, indicating a greater chance for cerebral injury. Percentage increases in GSI scores from drops 1 to 10 were 48.8, 54.3, 45.6, and 18.8 on the FD and 22.6, 35.9, 71.7, and 57.4 on the RD for the Sport Helmets Cascade, Cascade Air, Ultralite, and Bacharach Ultralite, respectively. CONCLUSIONS: Our findings indicate differences between helmets at the 2 drop sites and decreasing capacity of the helmets to dissipate forces with repetitive impacts.

Journal Article↗
PubMed1987

Particle-size distribution of bitolterol mesylate solution delivered by four compressed-air nebulizer devices.

The particle-size distribution of bitolterol mesylate solution delivered by four types of compressed-air nebulizers was determined. Before nebulization, bitolterol mesylate solution 0.2% w/v was diluted to 0.0833% w/v with 0.9% sodium chloride solution. The following commercially available nebulizers were tested: DeVilbiss Nebulizer Model 645, Hudson 1720 (Updraft) Hand Held Nebulizer, Bard Inspiron 002220 Mini-Neb Nebulizer, and Bunn Mini Mist Set model 0140-041. The particle-size distribution of nebulized solutions was determined with a cascade impactor contained in an in vitro apparatus designed to simulate use by a patient. Assays of bitolterol mesylate in the cascade impactor apparatus were done by high-performance liquid chromatography. Only slight differences were found in the particle-size distributions among the four types of nebulizers; the calculated average particle size ranged from 3.0 to 3.6 micron. All nebulizers tested showed satisfactory, comparable particle-size distributions and performance with bitolterol mesylate solution.

Aerosols↗
PubMed1997

Isolation and purification of superbins I and II from Austrelaps superbus (copperhead) snake venom and their anticoagulant and antiplatelet effects.

Two proteins with anticoagulant and antiplatelet activities were purified from Austrelaps superbus (copperhead) venom by gel filtration, ion-exchange and reverse-phase chromatographic methods. These purified proteins were designated superbins I and II. Superbin I was homogeneous, as indicated by electrospray ionization-mass spectrometry, with a mol. wt of 13,252.3 +/- 1.6, whereas superbin II contained two closely related proteins of mol. wts 13,235.5 +/- 1.1 and 13,212.9 +/- 1.2. Both superbins showed phospholipase A2 activity and exhibited weak anticoagulant effects when tested by one-step prothrombin time clotting assays. The 'dissection approach' was used to identify the coagulation complex(es) inhibited by these enzymes in the extrinsic coagulation cascade. The results indicate that both the enzymes inhibit the extrinsic tenase complex, but not the prothrombinase complex, similarly to other weakly anticoagulant phospholipases. Superbins I and II also inhibited aggregation of human platelets induced by collagen.

Anticoagulants↗
PubMed2000

Effect of flavonol derivatives on the carrageenin-induced paw edema in the rat and inhibition of cyclooxygenase-1 and 5-lipoxygenase in vitro.

Alkoxyflavonols were synthesized by the Algar-Flynn-Oyamada (AFO) cyclization of chalcones. Hydroxyflavonols were prepared by dealkylation of methoxyflavonols by refluxing in hydroiodic acid. The alkoxyflavonols 3-hydroxy-2-(2,3,4-trimethoxyphenyl)-4H-chromen-4-one (6), 2-(4-ethoxyphenyl)-3-hydroxy-4H-chromen-4-one (7), 2-(4-butoxyphenyl)-3-hydroxy-4H-chromen-4-one (10), and 2-(3-n-butoxyphenyl)-3-hydroxy-4H-chromen-4-one (11) as well as the trihydroxy derivative 3-hydroxy-2-(3,4,5-trihydroxyphenyl)-4H-chromen-4-one (18) displayed high anti-inflammatory activity in carrageenin-induced rat paw edema. Additionally, the inhibition of enzymes of the arachidonic acid cascade by the derivatives was investigated in vitro. In contrast to the natural compound quercetin, the compounds were more potent inhibiting cyclooxygenase-1 than 5-lipoxygenase except for 3-hydroxy-7-methoxy-2-(4-methoxyphenyl)-4H-chromen-4-one (5). No correlation between the anti-inflammatory activity in the rat paw edema test and the inhibition of 5-lipoxygenase or cyclooxygenase-1 could be observed. In conclusion, the present results suggest that other effects than inhibition of these enzymes of the arachidonic acid cascade are important for the anti-inflammatory activity of the investigated alkoxyflavonols.

Animals↗
PubMed1983

Does atropine block antigen-induced contraction in canine bronchial rings? A preliminary report.

Isometric contractions recorded with a strain gauge, were elicited with cumulative doses of ascaris suum antigen on fresh canine bronchial rings from 8 dogs. Fifteen rings from 2 spontaneously sensitized dogs reacted with contractions to the antigen, while 11 rings from other dogs did not react. Seven sensitized rings were re-challenged after atropine, which significantly prevented the antigen from contracting these rings at a time when antigen contracted 3 non-atropinized, simultaneously tested rings from the same bronchi. Acetylcholine may play a part in the smooth-muscle contraction induced by antigen, or atropine may inhibit early activation of the "arachidonic acid cascade". The findings may be of interest in the interpretation of anti-muscarinic drugs as inhibitors of reflex cholinergic activity versus local anti-allergic effect.

Animals↗