Search results for "histamine"
showing 10 items of 254 documents
Therapeutic Drug Monitoring of the Antidepressant Mirtazapine and Its N-Demethylated Metabolite in Human Serum
2004
Mirtazapine is a novel antidepressant that acts by enhancing serotonergic and noradrenergic neurotransmission. Because very little is known about serum concentrations in relation to clinical effects, the use of therapeutic drug monitoring is so far unclear. A rapid automated HPLC method with fluorescence detection was developed for routine quantification of mirtazapine and its demethylated metabolite N-desmethylmirtazapine in human serum. The precision of the method was suitable because the day-to-day (n = 7) coefficient of variation (CV) of mirtazapine was 9.8, 4.2, and 5.1% for concentrations of 10, 40, and 80 ng/mL, respectively, and the CV for N-desmethylmirtazapine were 11.6, 10.3, and…
Absence of tolerance in duodenal ulcer patients treated for 28 days with a bedtime dose of roxatidine or ranitidine
1996
There is much experimental work on the occurrence of tolerance to the antisecretory effect of H2-receptor antagonists in healthy subjects, while data on its development in patients with duodenal ulcer are poor and conflicting. Moreover, this phenomenon has not been studied previously with 24 h gastric pH-metry in patients with active duodenal ulcer. For these reasons, we carried out a prospective pharmacodynamic investigation in 48 patients with endoscopically proven duodenal ulcer using the well-established once daily dosing schedule of H2 blockers. They were studied by means of 24 h continuous endoluminal pH-metry which was performed before, on d1 and d28 after receiving an oral bedtime d…
Efficacy and pharmacological appropriateness of cinnarizine and dimenhydrinate in the treatment of vertigo and related symptoms
2021
Vertigo is not itself a disease, but rather a symptom of various syndromes and disorders that jeopardize balance function, which is essential for daily activities. It is an abnormal sensation of motion that usually occurs in the absence of motion, or when a motion is sensed inaccurately. Due to the complexity of the etiopathogenesis of vertigo, many pharmacological treatments have been tested for efficacy on vertigo. Among these drugs, cinnarizine, usually given together with dimenhydrinate, appears to be the first-line pharmacotherapy for the management of vertigo and inner ear disorders. Based on these considerations, the present non-interventional study aimed to investigate the clinical …
A European survey of management approaches in chronic urticaria in children: EAACI Paediatric Urticaria Taskforce
2021
Background: Although well described in adults, there are scarce and heterogeneous data on the diagnosis and management of chronic urticaria (CU) in children (0-18 years) throughout Europe. Our aim was to explore country differences and identify the extent to which the EAACI/GA²LEN/EDF/WAO guideline recommendations for paediatric urticaria are implemented. Methods: The EAACI Taskforce for paediatric CU disseminated an online clinical survey among EAACI paediatric section members. Members were asked to answer 35 multiple choice questions on current practices in their respective centres. Results: The survey was sent to 2,773 physicians of whom 358 (13.8%) responded, mainly paediatric allergist…
Histaprodifens: synthesis, pharmacological in vitro evaluation, and molecular modeling of a new class of highly active and selective histamine H(1)-r…
2000
A new class of histamine analogues characterized by a 3, 3-diphenylpropyl substituent at the 2-position of the imidazole nucleus has been prepared outgoing from 4,4-diphenylbutyronitrile (4b) via cyclization of the corresponding methyl imidate 5b with 2-oxo-4-phthalimido-1-butyl acetate or 2-oxo-1,4-butandiol in liquid ammonia, followed by standard reactions. The title compounds displayed partial agonism on contractile H(1) receptors of the guinea-pig ileum and endothelium-denuded aorta, respectively, except 10 (histaprodifen; 2-[2-(3, 3-diphenylpropyl)-1H-imidazol-4-yl]ethanamine) which was a full agonist in the ileum assay. While 10 was equipotent with histamine (1), methylhistaprodifen (…
DIFFERENT ABILITY OF TRIFLUOPERAZINE TO INHIBIT AGONIST-INDUCED CONTRACTION OF LUNG PARENCHYMA STRIPS FROM CONTROL AND SENSITIZED GUINEA-PIGS
1988
Abstract There is increasing interest in the therapeutic potential of calcium antagonists in asthma. Among them the use of calmodulin antagonists deserves consideration. In the present work the effect of trifluoperazine on contractions generated by different mechanisms (CaCl2, KCl, acetylcholine, histamine and 5-hydroxytryptamine) in lung parenchyma strip isolated from control and actively sensitized guinea-pigs has been studied. Trifluoperazine produced both in unsensitized and sensitized lung strips, a concentration-dependent, right, downward displacement of the concentration-response curves to the agonists used, although the sensitization procedure resulted in a potentiation in the abili…
Racemische Histamin-H1-Agonisten
1984
Es wurden racemische α- und β-methylverzweigte 2-(2-Aminoethyl)-thiazole und 2-(2-Aminoethyl)-imidazole (Isohistamine) dargestellt und auf Histamin-H1- und -H2-agonistische Aktivitat gepruft. Histamine Analogues, XXVI: Racemic Histamine H1-Agonists Racemic α or β-methylated 2-(2-aminoethyl)thiazoles and 2-(2-aminoethyl)imidazoles (isohistamines) were prepared and tested for histamine H1- and H2-agonistic activity.
Histaminanaloge, 27. Mitt. Bis (2,2′-histamine)
1985
Es wurden p-Phenylen-bis(2,2′-histamin) (6a), Ethylen-bis(2,2′-histamin) (6b), Tetramethylen-bis(2,2′-histamin) (6c) und Hexamethylen-bis(2,2′-histamin) (6d) dargestellt und auf Histamin-H1-und H2-agonistische Aktivitat untersucht. Histamine Analogues, XXVII: Bis(2,2′-histamines) p-Phenylenebis(2,2′-histamine) (6a), ethylenebis(2,2′-histamine) (6b), tetramethylenebis(2,2′-histamine) (6c), and hexamethylenebis(2,2′-histamine) (6d) were prepared and tested for histamine H1,-and H2-agonistic activity.
Acetylcholine and nicotine stimulate the release of granulocyte-macrophage colony stimulating factor from cultured human bronchial epithelial cells.
1998
Primary cultures of human bronchial epithelial cells (HBE-cells) were established to measure granulocyte-macrophage colony stimulating factor (GM-CSF) release. HBE-cells showed a basal GM-CSF release (82+/-20 ng/well/24 h; 30 donors), which was increased by interleukin-1 beta(IL-1beta, 1 ng/ml) by 270%. This effect was blocked by 1 microM dactinomycin or 10 microM cycloheximide, i.e. the stimulatory effect of IL-1beta depended on de-novo synthesis. Histamine (100 microM) and acetylcholine ( 100 nM) stimulated GM-CSF release more than two-fold above the baseline. Nicotine (1 microM) increased GM-CSF release to a similar extent, and this effect was prevented by 30 microM (+)-tubocurarine. The…
Influence of hormonal treatment on the response of the rat isolated uterus to histamine and histamine receptor agonists.
1992
The response of the isolated uterus to histamine and histamine agonists was investigated in progesterone- and oestrogen-treated rats. The uterine inhibitory responses to histamine and 4-methylhistamine (a histamine H2 receptor agonist) were similar in KCl-contracted uteri from progesterone- and oestrogen-treated rats. The histamine H1 receptor agonist, 2-pyridyl-ethylamine, produced a relaxant response only in progesterone dominant uterus. This was inhibited by the histamine H1 receptor antagonist. In the rat isolated uterus which was not preconstricted by KCl, neither histamine, 4-methylhistamine, nor 2-pyridyl-ethylamine produced any effect in the presence or absence of ranitidine. Raniti…