Search results for "Histamine"
showing 10 items of 254 documents
Quantitation of antihistamines in pharmaceutical preparations by liquid chromatography with a micellar mobile phase of sodium dodecyl sulfate and pen…
2002
Abstract A reversed-phase liquid chromatographic procedure with a micellar mobile phase of sodium dodecyl sulfate (SDS), containing a small amount of pentanol, was developed for the control of 7 antihistamines of diverse action in pharmaceutical preparations (tablets, capsules, powders, solutions, and syrups): azatadine, carbinoxamine, cyclizine, cyproheptadine, diphenhydramine, doxylamine, and tripelennamine. The retention times of the drugs were <9 min with a mobile phase of 0.15M SDS–6% (v/v) pentanol. The recoveries with respect to the declared compositions were in the range of 93–110%, and the intra- and interday repeatabilities and interday reproducibility were <1.2%. Th…
Advances in the molecular modeling and quantitative structure–activity relationship-based design for antihistamines
2013
Nowadays the use of antihistamines (AH) is increasing steadily. These drugs are able to act on a variety of pathological conditions of the organism. A number of computer-aided (in silico) approaches have been developed to discover and develop novel AH drugs. Among these methods stand the ones based on drug-receptor docking, thermodynamics, as well as the quantitative structure-activity relationships (QSAR).This review collates the most recent advances in the use of computer approaches for the search and characterization of novel AH drugs. Within the QSAR methods, particular attention will be paid to those based on molecular topology (MT) because of their demonstrated efficacy in discovering…
Leucine Aminopeptidase Activity in Mast Cells
1959
DURING investigations of the behaviour of leucine aminopeptidase activity of blood-serum in patients with dermatoses and tumours1–3, in a case of diffuse skin mastocytosis of a new-born, we detected heightened activity of leucine aminopeptidase. After mechanical friction of the affected skin, greater activity of leucine aminopeptidase occurred. From this we supposed a release of leucine aminopeptidase from the mast cell infiltrates of the skin. As is well known, in urticaria pigmentosa mechanical irritation of the skin lesions give rise to a degranulation of mast cells4,5 with liberation of histamine and serotonin. Indeed, there is no doubt that mast cells contain the enzyme leucine aminope…
Brain histamine and oleoylethanolamide restore behavioral deficits induced by chronic social defeat stress in mice.
2021
The physiological mechanisms underlying the complex interplay between life stressors and metabolic factors is receiving growing interest and is being analyzed as one of the many factors contributing to depressive illness. The brain histaminergic system modulates neuronal activity extensively and we demonstrated that its integrity is necessary for peripheral signals such as the bioactive lipid mediator oleoylethanolamide (OEA) to exert its central actions. Here, we investigated the role of brain histamine and its interaction with OEA in response to chronic social defeat stress (CSDS), a preclinical protocol widely used to study physio-pathological mechanisms underlying symptoms observed in d…
Label-free histamine detection with nanofluidic diodes through metal ion displacement mechanism
2017
[EN] We design and characterize a nanofluidic device for the label-free specific detection of histamine neurotransmitter based on a metal ion displacement mechanism. The sensor consists of an asymmetric polymer nanopore fabricated via ion track-etching technique. The nanopore sensor surface having metal-nitrilotriacetic (NTA-Ni2+) chelates is obtained by covalent coupling of native carboxylic acid groups with N-alpha,N-alpha-bis(carboxymethyl)-L-lysine (BCML), followed by exposure to Ni2+ ion solution. The BCML immobilization and subsequent Ni2+ ion complexation with NTA moieties change the surface charge concentration, which has a significant impact on the current-voltage (I-V) curve after…
Effects of ouabain on human bronchial muscle in vitro
2003
The effects of ouabain, an inhibitor of the plasmalemmal Na(+)/K(+)-ATPase activity, were examined in human isolated bronchus. Ouabain produced concentration-dependent contraction with -logEC(50)=7.16+/-0.11 and maximal effect of 67+/-4% of the response to acetylcholine (1 mM). Ouabain (10 microM)-induced contraction was epithelium-independent and was not depressed by inhibitors of cyclooxygenase and lipoxygenase, antagonists of muscarinic, histamine H(1)-receptors and alpha-adrenoceptors, or neuronal Na(+) channel blockade. The inhibition of ouabain contraction in tissues bathed in K(+)-free medium, and the inhibition by ouabain of the K(+)-induced relaxation confirm that the contractile a…
Halothane inhibits endothelium-dependent relaxation elicited by acetylcholine in human isolated pulmonary arteries.
1997
This study examined whether a clinically relevant concentration of the volatile anaesthetic halothane modifies the endothelium-dependent relaxation produced by acetylcholine (3 nM-10 microM), histamine (1 pM-0.1 microM) and anti-human immunoglobulin E (1:1000) in human isolated pulmonary arteries submaximally precontracted with noradrenaline. An inhibitor of nitric oxide formation, N(G)-nitro-L-arginine (100 microM), attenuated acetylcholine-induced relaxation but failed to inhibit histamine- and anti-human immunoglobulin E-induced relaxation. Indomethacin (2.8 microM, a cyclooxygenase inhibitor) preferentially reduced the relaxation to histamine and anti-human IgE. Halothane (2%) significa…
Pharmacological properties of the methanol extract from Mentha suaveolens Ehrh.
2002
The present study analyses the pharmacological activity in in vivo and in vitro models of the methanol extract obtained from the leaves and steams of Menta suaveolens Ehrh. This extract lacked toxicity, but exhibited a central nervous system depressant action; an analgesic effect in models of chemical and mechanical stimulation suggesting the induction of a peripheral analgesic response. The extract also exhibited an antiinflammatory action inhibiting the rat paw oedema induced by carrageenin. Moreover, the in vitro studies showed a significant diminution in the contractile effects induced by histamine, serotonin and acetylcholine.
Peripheral Neuropathy in the Hypereosinophilic Syndrome: A Case Report
1989
We observed a patient with the hypereosinophilic syndrome that showed as a prominent clinical feature peripheral nerve dysfunction. The neuropathy evolved over 4 months and affected sensory and motor functions. Nerve conduction studies and EMG were compatible with axonal neuropathy. Nerve and muscle biopsies revealed severe axonal degeneration with neurogenic atrophy of muscle. Morphometry of peroneal nerve showed marked axonal loss, more prominent in large myelinated fibers. There was no evidence of vasculitis process. Neuropathy is produced by eosinophil-released substances exerting a neurotoxic effect through direct altered vascular endothelial permeability and local mast cell histamine …
Migration of monocytes after intracerebral injection at entorhinal cortex lesion site.
2012
Abstract After axonal lesion in the CNS, intracerebrally injected green fluorescent monocytes migrate through the cribroid plate and subsequently accumulate in deep cervical lymph nodes. The lack of classical lymph vessels within brain tissue complicates immune surveillance of the CNS, and therefore, cellular emigration out of the CNS parenchyma requires alternate pathways. Whereas invasion of blood-derived mononuclear cells and their transformation into ramified, microglia-like cells in areas of axonal degeneration across an intact BBB have been demonstrated, it still remained unclear whether these cells reside permanently, undergo apoptosis, or leave the brain to present antigen in lympho…