Search results for "Muscarinic"

Stable expression in HEK-293 cells of the rat alpha3/beta4 subtype of neuronal nicotinic acetylcholine receptor.

1996

The alpha3/beta4 subtype of neuronal nicotinic acetylcholine receptor (nAChR) was stably expressed in human embryonic kidney (HEK) 293 cells that co-expressed a voltage-gated Ca2+ channel. alpha3/beta4-nAChR-expressing clones were identified using the fura-2 Ca2+ imaging technique, and were further characterised by single-cell and whole-cell patch-clamp studies. Acetylcholine (ACh) induced fast activating currents which showed desensitisation and inward rectification. The conductance of the ACh-activated channel was 29 pS. The order of potency of the nicotinic agonists tested was cytisine approximately = nicotine > acetylcholine. The EC50 value for ACh was 145 microM; the Hill coefficient w…

Effects of two-carbon bridge region methoxylation of benztropine: discovery of novel chiral ligands for the dopamine transporter

2001

6-Methoxylated and 8-oxygenated benztropines were prepared and evaluated for their DAT and SERT activity (binding and uptake inhibition). Methoxylation at the two-carbon bridge of benztropine produced a novel class of potent and selective DAT ligands. An interesting enantioselectivity was also observed for this new class of chiral benztropines. The inactivity of the 8-oxygenated analogues seems to point out that, unlike cocaine and its analogues, interactions of benztropine ligands with DAT may be strongly governed by the nitrogen atom.

A second pathway of activation of the Torpedo acetylcholine receptor channel

1991

We have studied the interaction of the reversible acetylcholine esterase inhibitor (-)physostigmine (D-eserine) with the nicotinic acetylcholine receptor (nAChR) from Torpedo marmorata electric tissue by means of ligand-induced ion flux into nAChR-rich membrane vesicles and of equilibrium binding. We find that (-) physostigmine induces cation flux (and also binds to the receptor) even in the presence of saturating concentrations of antagonists of acetylcholine, such as D-tubocurarine, alpha-bungarotoxin or antibody WF6. The direct action on the acetylcholine receptor is not affected by removal of the methylcarbamate function from the drug and thus is not due to carbamylation of the receptor…

A muscarinic mechanism inhibiting the release of noradrenaline from peripheral adrenergic nerve fibres by nicotinic agents.

1968

Structure-activity relationships of dimethindene derivatives as new M2-selective muscarinic receptor antagonists.

2003

A series of 2,3-disubstituted indenes, which are analogues of the widely used histamine H(1) receptor antagonist dimethindene, have been synthesized and studied as muscarinic and histamine receptor antagonists. The affinities of these compounds for the five human muscarinic receptor subtypes (M(1)-M(5)) and for human histamine H(1) receptors were determined in radioligand binding studies using membranes from transfected Chinese hamster ovary (CHO) cells and [(3)H]N-methylscopolamine ([(3)H]NMS). The results demonstrate that the diisopropyl analogue 19 has a similar high affinity as (S)-dimethindene at M(2) receptors ((S)-dimethindene: pK(i) = 7.52; (-)-19: pK(i) = 7.37) with an improved sel…

Profile of glycopyrronium for once-daily treatment of moderate-to-severe COPD

2012

Bronchodilators are central in the symptomatic management of chronic obstructive pulmonary disease (COPD). Long-acting muscarinic antagonists (LAMAs) and long-acting β(2)-agonists (LABAs) are the main classes of long-acting bronchodilators. To date, tiotropium is the only once-daily LAMA available for the treatment of COPD. Glycopyrronium is a novel LAMA, currently in development for COPD. Phase II studies have shown that glycopyrronium 50 μg once daily provides clinically significant 24-hour bronchodilation with a rapid onset of action, which is faster than that of tiotropium, and a favorable safety and tolerability profile. The Phase III GLycopyrronium bromide in COPD airWays (GLOW) progr…

Effects of aclidinium on determinants of COPD severity: symptoms and quality of life

2016

Marco Contoli,1 Paolo Solidoro,2 Fabiano Di Marco,3,4 Nicola Scichilone,5 Angelo Corsico,6 Fulvio Braido,7 Pierachille Santus4,8 1Research Centre on Asthma and COPD, Department of Medical Sciences, University of Ferrara, Ferrara, Italy; 2Cardiovascular and Thoracic Department, Città della Salute, Turin, Italy; 3Department of Health Sciences, University of Milan, Milan, Italy; 4Respiratory Unit, San Paolo Hospital, Milan, Italy; 5Department of Internal Medicine, Section of Pulmonology (DIBIMIS), University of Palermo, Palermo, Italy; 6Department of Molecular Medicine, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; 7Allergy and Respiratory Diseases Clinic, DIMI, University of G…

Detection of Fibroblast Growth Factor Receptor 1 (FGFR1) Transactivation by Muscarinic Acetylcholine Receptors (mAChRs) in Primary Neuronal Hippocamp…

2018

In addition to their canonical intracellular signals involved in the regulation of neuronal plasticity, G-protein coupled receptors can also rapidly transactivate tyrosine kinase receptors and their downstream intracellular signaling in absence of specific ligands. Here we describe our protocol for dissociating and maintaining hippocampal primary neurons in high- and low-density culture, followed by a description of methods employed to evaluate neurite outgrowth and protein phosphorylation associated with fibroblast growth factor receptor 1 transactivation by muscarinic acetylcholine receptors. Our goal was to provide the reader with detailed protocols of the abovementioned techniques and t…

Interactions between cholinergic and fibroblast growth factor receptors in brain trophism and plasticity

2014

Acetylcholine, acting on both nicotinic receptors (nAChRs) and muscarinic receptors (mAChRs), plays a role in the regulation of synaptic plasticity, being involved in the regulation of cellular processes and cognitive functions, such as learning, memory and attention. Recently, G protein coupled receptors (GPCRs), including mAChRs, have been reported to transactivate tyrosine-kinase receptors (RTK), such as epidermal growth factor receptor (EGFR), and initiate their intracellular signaling. In this minireview we have first analysed the RTK transactivation mechanisms, involving cholinergic receptors, and thereafter the interplay between AChR and neurotrophic factor systems built up by FGF2 a…

Effects of a structured educational intervention in moderate-to-severe elderly asthmatic subjects.

2019

Background: Adherence to inhaled drugs is linked to patients’ satisfaction with their device, and an incorrect use can negatively affect the outcomes of asthma treatment. We speculated that this is particularly true in elderly asthmatic subjects. Aim: We performed a national pre-post interventional multicentre study, enrolling moderate-to-severe asthmatic subjects aged ≥65 ​years treated with fixed inhaled combination drugs by dry powder inhaler (DPI) or pressurized metered dose inhaler (pMDI). Adherence and critical errors were evaluated by means of validated questionnaires at first visit (V1) and after 3–6 months (V2). At V1, subjects underwent intensive training on the correct use of the…