Search results for "Fenoterol"
showing 10 items of 11 documents
Oral Sustained-Release Aminophylline and Bronchodilator Response to Inhaled Fenoterol in Patients with Chronic Airflow Obstruction
1985
The bronchodilator response to inhaled fenoterol (400 micrograms) was examined in the morning and in the afternoon before and during oral sustained-release aminophylline treatment in eight patients with chronic reversible airway obstruction. Bronchodilatation was evaluated by measuring serial peak expiratory flow rates (PEFR) for eight hours after inhaled fenoterol and calculating the area under the time-response curves and the percentage increment from the baseline values. The patients showed an enhancement of the bronchodilatation achieved with fenoterol in the morning during aminophylline treatment. In the afternoon, instead, the effect of the fenoterol was not improved by oral aminophyl…
Control of the production of oxygen intermediates of human polymorphonuclear leukocytes and monocytes by beta-adrenergic receptors.
1983
The control by beta-adrenergic receptors of the production of oxygen radicals by zymosan-stimulated human polymorphonuclear leukocytes (PMN) and monocytes (M phi) was studied in vitro by means of chemiluminescence. In addition we asked whether PMN and M phi exhibit differential sensitivity to beta-adrenergic stimulation. For beta-adrenergic stimulation we applied fenoterol ranging from 10(-5) to 10(-9) M x 2.7. We found a dose-dependent suppression of the production of oxygen radicals, the ID50 being approximately 10(-6) M both for PMN and M phi. By assessment of lactic dehydrogenase release a cytotoxic effect of the drug could be ruled out. When incubated together with the beta-adrenergic …
Urinary Bladder Weight and Function in a Rat Model of Mild Hyperglycemia and Its Treatment With Dapagliflozin
2019
Hypertrophy and dysfunction of the urinary bladder are consistently observed in animal models of type 1 and less consistently in those of type 2 diabetes. We have tested the effects of mild hyperglycemia (n = 10 per group) in a randomized, blinded study and, in a blinded pilot study, of type 2 diabetes (n = 6 per group) and its treatment with dapagliflozin (1 mg/kg per day) on weight, contraction, and relaxation of the rat bladder. Based on a combination of high-fat diet and a low dose of streptozotocin, animals in the main study reached a mean peak blood glucose level of about 300 mg/dl, which declined to 205 mg/dl at study end. This was associated with a small, if any, increase in bladder…
Synthesis and preliminary evaluation of (R,R)(S,S) 5-(2-(2-[4-(2-[18F]fluoroethoxy)phenyl]-1-methylethylamino)-1-hydroxyethyl)-benzene-1,3-diol ([18F…
2003
The 18 F-labeled b2-adrenergic receptor ligand (R,R)(S,S) 5-(2-(2-(4-(2-( 18 F)fluoroethoxy)phenyl)-1-methylethylamino)-1- hydroxyethyl)-benzene-1,3-diol, a derivative of the original highly selective racemic fenoterol, was synthesized in an overall radio- chemical yield of 20% after 65 min with a radiochemical purity higher than 98%. The specific activity was in the range of 50-60 GBq/mmol. In vitro testing of the non-radioactive fluorinated fenoterol derivative with isolated guinea pig trachea was conducted to obtain an IC50 value of 60 nM. Preliminary ex vivo organ distribution and in vivo experiments with positron emission tomography (PET) on guinea pigs were performed to study the biod…
Effect throughout the day of inhaled fenoterol on the bronchial responsiveness to histamine in asthmatic patients.
1987
The effect throughout the day of inhaled fenoterol on the bronchial responsiveness to inhaled histamine was evaluated in 8 asthmatic patients. The airway response to increasing concentration of histamine aerosol was assessed by measurement of forced expiratory volume in one second (FEV1). The provocative dose of histamine needed to cause a 20% fall in starting FEV1 was calculated from the cumulative log dose response curves. Histamine challenges were performed in duplicate, on separate days, after premedication with placebo or fenoterol given by metered dose inhalers in the morning and in the afternoon. The mean starting FEV1 in the morning and in the afternoon did not change significantly …
Spontaneous labour at term is associated with fetal monocyte activation.
1999
SUMMARYThe aetiology of both term and preterm labour remains incompletely understood. Maternal infectious diseases as well as intra-uterine infections were shown to be a well established cause of uncontrollable preterm delivery, indicating that inflammatory reactions, regulated by maternal immunecompetent cells, are implicated in labour-promoting mechanisms. To investigate the possibility that the activation of the fetal immune system may be involved in labour induction, we examined cytokine production patterns of different cord blood cell populations obtained from neonates after spontaneous onset of normal term labour and vaginal delivery (n = 25), vaginal delivery but induced term labour …
Effects of Inhaled Fenoterol on the Circadian Rhythm of Expiratory Flow in Allergic Bronchial Asthma
1983
Metered-dose aerosol treatment with fenoterol for three consecutive days, in eight patients suffering from allergic asthma, caused the disappearance of FEV1 and MEF50 circadian rhythm. We attribute such behavior to the suppression of the bronchomotor tone induced by fenoterol. The administration on different days of a single dose of fenoterol aerosol in another group of eight patients pointed out the variability of the effects of the drug at different hours of the day. We believe the results obtained are important for a better dosage and time distribution of the therapy with beta2 agonists.
Validation of Fenoterol to Study β<sub>2</sub>-Adrenoceptor Function in the Rat Urinary Bladder
2021
Fenoterol is a β<sub>2</sub>-adrenoceptor (AR)-selective agonist that is commonly used to investigate relaxation responses mediated by β<sub>2</sub>-AR in smooth muscle preparations. Some data have questioned this because fenoterol had low potency in the rat urinary bladder when a muscarinic agonist was used as a pre-contraction agent and because some investigators proposed that fenoterol may act in part via β<sub>3</sub>-AR. We designed the present study to investigate whether fenoterol is a proper pharmacological tool to study β<sub>2</sub>-AR-mediated relaxation responses in the rat urinary bladder. Firstly, we have compared the effect of p…
Synthesis of [18F]-Fluoroethylfenoterol for imaging β2 receptor status in lung in vivo
2001
5-(-{2-[4-(2-[18F]Fluoroethoxy)-phenyl]-l-methyl-ethylamino}-l-hydroxy-ethyl)-benzene-1, 3-diol ([18F]fluoroethylfenoterol) was synthesised from 4-(2-{benzyl-[2-(3,5-bis-benzyloxy-phenyl)-2-hydroxy-ethyl]-amino}-propyl)-phenol using 2-[18F]fluoroethyltosylate (92% RCY) followed by reductive cleavage of the benzyl protecting groups. Preliminary in vitro tests showed [19F]fluoroethylfenoterol to be as potent in relaxation of lung tissue as fenoterol itself.
STIMULATION OF ?1-ADRENOCEPTORS ENHANCES ELECTRICALLY EVOKED [3H]-ACETYLCHOLINE RELEASE FROM RAT PHRENIC NERVE
1990
1. The effects of isoprenaline, noradrenaline and fenoterol on the electrically evoked release of [3H]-acetylcholine from the rat phrenic nerve were investigated. 2. Isoprenaline (0.1 mumol/L) and noradrenaline (1 mumol/L) enhanced evoked [3H]-acetylcholine release by about 90%, an effect which was abolished by CGP 20712A (0.1 mumol/L), a specific antagonist at beta 1-adrenoceptors. Noradrenaline still enhanced [3H]-acetylcholine release in the presence of phentolamine (1 mumol/L). 3. The enhancing effect of both isoprenaline and noradrenaline decreased at prolonged exposure times (24-32 min). A pre-exposure of the tissue to a low concentration (0.01 mumol/L) of isoprenaline prevented the e…