Search results for "Muscarinic receptor"
showing 8 items of 8 documents
“Smoke, Choline-Acetyl-Transferase, Muscarinic Receptors and fibroblast proliferation in COPD
2009
Acetylcholine (ACh), synthesized by choline acetyltransferase (ChAT), and muscarinic M1, M2, and M3 receptors (MRs) are involved in fibroblast proliferation. We evaluated ChAT, MRs, and extracellular signal-regulated kinase (ERK) 1/2 and nuclear factor (NF) κB activation in lung fibroblasts from patients with chronic obstructive pulmonary disease (COPD), control smokers, and controls. Human fetal lung fibroblasts (HFL-1) stimulated with interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and cigarette smoke extracts (CSEs) were evaluated for ChAT and MR expression. We tested the effects of ACh on fibroblast proliferation and its ability to bind fibroblasts from patients with COPD, control s…
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…
Salivary gland proteins alterations in the diabetic milieu
2021
AbstractSalivary glands are considered the chief exocrine glands of the mouth and physiologically contribute to the maintenance of the homeostasis of the oral cavity. They consist of the parotid, submandibular and sublingual glands, which come in pairs and are collectively called the major glands, and the minor glands, which are much smaller and are dispersed throughout the buccal cavity. Salivary glands are distinguished by their size, amount of saliva secretion and their location in the oral cavity. Salivary glands pathophysiology has been a subject of interest in various worldwide metabolic disorders, including diabetes mellitus. Diabetes mellitus (DM), a global health concern, with a pa…
Muscarinic type-1 receptors contribute to I-K,I-ACh in human atrial cardiomyocytes and are upregulated in patients with chronic atrial fibrillation
2018
Background: Basal and acetylcholine-gated inward-rectifier K+-currents (I-K1 and I-K,I-ACh, respectively) are altered in atrial fibrillation (AF). G(i)-protein-coupled muscarinic (M) receptors type-2 are considered the predominant receptors activating I-K,I-ACh. Although a role for G(q)-coupled non-M-2-receptor subtypes has been suggested, the precise regulation of I-K,I-ACh by multiple M-receptor subtypes in the human atrium is unknown. Here, we investigated M-1-receptor-mediated I-K,I-ACh regulation and its remodeling in chronic AF (cAF). Methods and results: M-1-receptor mRNA and protein abundance were increased in atrial cardiomyocyte fractions and atrial homogenates from cAF patients, …
Heat shock protein (Hsp) regulation by muscarinic acetylcholine receptor (mAChR) activation in the rat hippocampus.
2018
The cholinergic system plays a crucial role in modulating in the central nervous system physiological responses such as neurogenesis, neuronal differentiation, synaptic plasticity, and neuroprotection. In a recent study, we showed that Oxotremorine-M, a non-selective muscarinic acetylcholine receptor agonist, is able to transactivate the fibroblast growth factor receptor and to produce a significant increase in the hippocampal primary neurite outgrowth. In the present study we aimed to explore in the rat hippocampus the possible effect of acute or chronic treatment with Oxotremorine-M on some heat shock proteins (Hsp60, Hsp70, Hsp90) and on activation of related transcription factor heat sh…
Cigarette smoke extract activates human bronchial epithelial cells affecting non-neuronal cholinergic system signalling in vitro.
2010
Abstract Aims Acetylcholine (ACh) is synthesized by Choline Acetyl-Transferase (ChAT) that exerts its physiological effects in airway epithelial cells via muscarinic receptor (MR) activation. We evaluate the effect of ACh stimulation on human bronchial epithelial cells (16-HBE) and test whether cigarette smoke extract (CSE) can modify the basal cellular response to ACh affecting the non-neuronal cholinergic system signalling. Main methods ACh stimulated 16-HBE were tested for ACh-binding, Leukotriene B 4 (LTB 4 ) release and ERK1/2 and NFkB pathway activation. Additionally, we investigated all the aforementioned parameters as well as ChAT and MR proteins and mRNA expression and endogenous A…
Characterization of the muscarinic receptor subtype(s) mediating contraction of the guinea-pig lung strip and inhibition of acetylcholine release in …
1997
1 The muscarinic receptor subtypes mediating contraction of the guinea-pig lung strip and inhibition of the release of acetylcholine from cholinergic vagus nerve endings in the guinea-pig trachea in vitro have previously been characterized as M-2-like, i.e. having antagonist affinity profiles that are qualitatively similar but quantitatively dissimilar compared to cardiac M-2 receptors. The present study sought to establish definitely the identity of these receptor subtypes by using the selective muscarinic receptor antagonist, tripitramine. Guinea-pig atria and guinea-pig trachea (postjunctional contractile response) were included for reference.2 It was found that tripitramine antagonized …
Aged Mice Devoid of the M3 Muscarinic Acetylcholine Receptor Develop Mild Dry Eye Disease
2021
The parasympathetic nervous system is critically involved in the regulation of tear secretion by activating muscarinic acetylcholine receptors. Hence, various animal models targeting parasympathetic signaling have been developed to induce dry eye disease (DED). However, the muscarinic receptor subtype (M1–M5) mediating tear secretion remains to be determined. This study was conducted to test the hypothesis that the M3 receptor subtype regulates tear secretion and to evaluate the ocular surface phenotype of mice with targeted disruption of the M3 receptor (M3R−/−). The experimental techniques included quantification of tear production, fluorescein staining of the ocular surface, environmenta…