Search results for "Histamine"
showing 10 items of 254 documents
Decreased release of histamine and sulfidoleukotrienes by human peripheral blood leukocytes after wasp venom immunotherapy is partially due to induct…
1999
Abstract Background: Recent studies provide evidence that venom immunotherapy (VIT) alters the pattern of cytokine production by inducing an allergen-specific T-cell shift in cytokine expression from T H2 (IL-4, IL-5) to T H1 (IFN-γ) cytokines and also inducing the production of IL-10. Objective: This study was carried out to analyze whether these changes in cytokine production of T cells already observed 1 week after the initiation of VIT in subjects with wasp venom allergy also influence the reactivity of effector cells, such as mast cells and basophils. Methods: All subjects included in this study had a history of severe systemic allergic reactions to wasp stings and positive skin test r…
Adjuvant effects of aluminium hydroxide-adsorbed allergens and allergoids – differences in vivo and in vitro
2014
Summary Allergen-specific immunotherapy (SIT) is a clinically effective therapy for immunoglobulin (Ig)E-mediated allergic diseases. To reduce the risk of IgE-mediated side effects, chemically modified allergoids have been introduced. Furthermore, adsorbance of allergens to aluminium hydroxide (alum) is widely used to enhance the immune response. The mechanisms behind the adjuvant effect of alum are still not completely understood. In the present study we analysed the effects of alum-adsorbed allergens and allergoids on their immunogenicity in vitro and in vivo and their ability to activate basophils of allergic donors. Human monocyte derived dendritic cells (DC) were incubated with native …
Antiasthmatic Effects of <i>Picrorhiza kurroa</i>: Androsin Prevents Allergen- and PAF-induced Bronchial Obstruction in Guinea Pigs
1991
In the Ayurvedic medicine, <i>Picrorhiza kurroa </i>Royle ex Benth. is used for the treatment of liver and lung diseases. Using different chemical and pharmacological methods, we could identify the phenol glycoside androsin as active compound preventing allergen and platelet-activating factor induced bronchial obstruction in guinea pigs in vivo (10 mg/kg p.o.; 1 h prior to the inhalation challenge). Histamine release from human polymorphonuclear leukocytes in vitro was inhibited by other compounds yet to be identified.
The relationship between asthma and allergic rhinitis: exploring the basis for a common pathophysiology
2003
Summary Most patients with asthma also have rhinitis, and the same inflammatory cells and mechanisms are present in bronchial and nasal mucosa, thus leading to the concept of ‘one airway, one disease’. This concept is further substantiated by evidence of nasal inflammation in asthma, and bronchial inflammation and hyperresponsiveness in rhinitis. Endobronchial allergen challenge induces nasal and bronchial symptoms as well as reductions in pulmonary function and nasal patency. Likewise, treating rhinitis can improve the symptoms of asthma. There are some notable pathophysiological differences between the nose and the bronchi, for example airway remodelling appears to be less extensive in th…
Mast cells and the development of allergic airway disease
2008
Murine models have highlighted the importance of T-cells and TH2 cytokines in development of allergen-induced airway disease. In contrast, the role of mast cells for the development of allergic airway disease has been controversial. Recent studies in murine models demonstrate a significant contribution of mast cells during the development of airway hyperresponsiveness and airway inflammation. Furthermore these models have allowed identifying certain mast cell-produced mediators (e.g. histamine and leukotriene B4) to be involved in the recruitment of effector T-cells into the lung. Additionally, mast cell-produced TNF can directly activate TH2 cells and contribute to the development of aller…
Histamine and its possible role in cytolysis of white blood cells in guinea pigs sensitized with tubercle bacilli.
1962
DELAYED or tuberculin-type sensitivity is–apart from some single publications–only transferable by white blood cells or peritoneal cells but not with humoral antibodies of sensitized organisms1. In vitro, after addition of antigen, a lysis of white blood cells2 is seen up to 35 per cent2. That effect is preceded by morphological changes3–5. Cytolysis in the presence of plasma will be discussed elsewhere. Labelled lymphoid cells of sensitized guinea pigs will be found after transfer to normal animals at the side of the dermal tuberculin reaction6. The importance of white cells is further revealed by the fact that the tuberculin reaction will be suppressed by a specific anti-lymphocytic serum…
Phencyclidine-induced disruption of oscillatory activity in prefrontal cortex: Effects of antipsychotic drugs and receptor ligands
2016
The non-competitive NMDA receptor (NMDA-R) antagonist phencyclidine (PCP) markedly disrupts thalamocortical activity, increasing excitatory neuron discharge and reducing low frequency oscillations (LFO, <4Hz) that temporarily group neuronal discharge. These actions are mainly driven by PCP interaction with NMDA-R in GABAergic neurons of the thalamic reticular nucleus and likely underlie PCP psychotomimetic activity. Here we report that classical (haloperidol, chlorpromazine, perphenazine) and atypical (clozapine, olanzapine, quetiapine, risperidone, ziprasidone, aripripazole) antipsychotic drugs - but not the antidepressant citalopram - countered PCP-evoked fall of LFO in the medial prefron…
Chaperone patterns in vernal keratoconjunctivitis are distinctive of cell and Hsp type and are modified by inflammatory stimuli
2016
Background Vernal keratoconjunctivitis (VKC) is a severe ocular allergy with pathogenic mechanism poorly understood and no efficacious treatment. The aims of the study were to determine quantities and distribution of Hsp chaperones in the conjunctiva of VKC patients and assess their levels in conjunctival epithelial and fibroblast cultures exposed to inflammatory stimuli. Methods Hsp10, Hsp27, Hsp40, Hsp60, Hsp70, Hsp90, Hsp105, and Hsp110 were determined in conjunctiva biopsies from nine patients and nine healthy age-matched normal subjects, using immunomorphology and qPCR. Conjunctival epithelial cells and fibroblasts were cultured and stimulated with IL-1β, histamine, IL-4, TNF-α, or UV-…
Histamine inhibits 5-hydroxytryptamine release from the porcine small intestine: Involvement of H3 receptors
1992
Abstract Strips of the porcine small intestine were incubated in vitro, and the release of 5-hydroxytryptamine (5-HT) was determined by high-pressure liquid chromatography with electrochemical detection. Removal of the mucosa resulted in a large reduction (95%) of tissue 5-HT, suggesting that enterochromaffin cells are the main source of 5-HT. The release of 5-HT was reduced by 70% after omission of calcium. Tetrodotoxin and hexamethonium reduced the release of 5-HT by 30%–40% in a nonadditive manner, indicating a spontaneous neuronal (nicotinic) excitatory input to the enterochromaffin cells. Histamine inhibited the release of 5-HT by about 50%. This effect was not affected by mepyramine o…
Measurement of inflammatory mediators of mast cells and eosinophils in native nasal lavage fluid in nasal polyposis.
2001
<i>Background:</i> Nasal polyposis (NP) often coexists with asthma, rhinitis and sinusitis. Polyp histology typically shows chronic, eosinophilic inflammation. The inflammatory cell infiltrate generally includes eosinophils, lymphocytes, plasma cells and mast cells. <i>Objective:</i> To gain insight into the natural history of NP, we analysed mediator levels and leukocyte values in nasal fluids and eosinophil cationic protein (ECP), total IgE levels and eosinophils in the blood in several groups of both allergic and non-allergic patients with nasal polyps and in patients with allergic rhinitis (AR). <i>Methods:</i> Thirty-two patients with nasal polyps en…