Search results for "Cholinergic"
showing 10 items of 251 documents
The effects of several muscarinic antagonists on pre- and postsynaptic receptors in the isolated rabbit heart
1981
In order to reveal possible differences between pre- and postsynaptic muscarine receptors, seven antagonists were tested for their affinities on these receptor sites in the rabbit isolated perfused heart. Methacholine was used as an agonist to inhibit the noradrenaline overflow evoked by electrical stimulation (3 Hz, 3 min) of the sympathetic nerves (presynaptic parameter) and to decrease the systolic tension development of the right atrium (postsynaptic parameter). The affinity of an antagonist was expressed as pA2. A decreasing order of potency was obtained with ipratropium, scopolamine, atropine, trihexyphenidyl, amitriptyline, and gallamine, both for pre- and postsynaptic responses. The…
Expression of nicotinic acetylcholine receptor subunits in the cerebral cortex in Alzheimer's disease: histotopographical correlation with amyloid pl…
1999
Impairment of cholinergic transmission and decreased numbers of nicotinic binding sites are well-known features accompanying the cognitive dysfunction seen in Alzheimer's disease (AD). In order to elucidate the underlying cause of this cholinoceptive dysfunction, the expression of two pharmacologically different nicotinic acetylcholine receptor (nAChR) subunits (alpha4, alpha7) was studied in the cerebral cortex of Alzheimer patients as compared to controls. Patch-clamp recordings of 14 dissociated neurons of control cortices showed responses suggesting the existence of alpha4- and alpha7-containing functional nAChRs in the human cortex. In cortices of Alzheimer patients and controls, the p…
Involvement of CB1 and CB2 receptors in the modulation of cholinergic neurotransmission in mouse gastric preparations.
2007
Abstract While most of the studies concerning the role of cannabinoids on gastric motility have focused the attention on the gastric emptying in in vivo animal models, there is little information about the cannabinoid peripheral influence in the stomach. In addition, the functional features of CB2 receptors in the gastrointestinal tract have been poorly characterized. The purpose of the present study was to investigate the effects of cannabinoid drugs on the excitatory cholinergic and inhibitory non-adrenergic non-cholinergic (NANC) neurotransmission in mouse isolated gastric preparations. Intraluminal pressure from isolated whole stomach was recorded and mechanical responses induced by ele…
Mildronate enhances learning/memory and changes hippocampal protein expression in trained rats.
2013
Previously we demonstrated that mildronate [3-(2,2,2-trimethylhydrazinium) propionate dihydrate], a representative of the aza-butyrobetaine class of compounds, protects mitochondrial metabolism under conditions such as ischemia. Mildronate also acted as a neuroprotective agent in an azidothymidine-induced mouse model of neurotoxicity, as well as in a rat model of Parkinson's disease. These observations suggest that mildronate may stimulate processes involved in cell survival and change expression of proteins involved in neurogenic processes. The present study investigated the influence of mildronate on learning and memory in the passive avoidance response (PAR) test and the active condition…
Muscarinic Properties of Compounds Related to Arecaidine Propargyl Ester
2011
A series of new analogues of the arecaidine propargyl ester (CAS 35516-99-5, APE, 1a) with alcohols consisting of 4 or 5 carbon atoms were investigated at muscarinic receptor subtypes. The muscarinic activity of the quaternary and tertiary salts of the APE-related compounds were assayed on the isolated guinea-pig ileum (M 3 receptor subtype) and guinea-pig left atria (M 2 receptor subtype) as well as on rabbit isolated vas deferens (M 1 receptor subtype). The structural variations made in the APE molecule, replacing the triple bond in the ester side chain with structures such as double bond, an allene moiety, a single bond, a cyclopropyl group or two triple bonds should alter the selectivit…
Isolation of Cholinergic Synaptic Vesicles from the Myenteric Plexus of Guinea-Pig Small Intestine
1980
The acetylcholine-rich myenteric plexus-longitudinal muscle preparation of the guinea-pig small intestine has been subjected to subcellular fractionation using modifications of both classical methods and that originally devised for bulk isolation of cholinergic synaptic vesicles from the electromotor nerve terminals of Torpedo marmorata by means of density gradient centrifugation in a zonal rotor. The latter method gave a vesicle fraction with the highest acetylcholine content so far recorded for a mammalian particulate fraction, 30.9 +/- S.E.M. 1.8 (5) nmol of acetylcholine . mg of protein-1. Electron-microscopical examination showed that it consisted of a homogeneous preparation of vesicl…
Increased levels of Th17 cells are associated with non-neuronal acetylcholine in COPD patients.
2014
T-lymphocytes, including Th17-cells and T-cells expressing acetylcholine (ACh), are key components of systemic inflammation in chronic obstructive pulmonary disease (COPD). We investigated whether ACh promotes Th17 cells in COPD. ACh, IL-17A, IL-22, RORγt, FOXP3 expression and AChIL-17A, AChIL-22, AChRORγt coexpression was evaluated in peripheral blood mononuclear cells (PBMC) from COPD patients (n=16), healthy smokers (HS) (n=12) and healthy control subjects (HC) (n=13) (cultured for 48 h with PMA) by flow cytometry. Furthermore, we studied the effect of Tiotropium (Spiriva®) (100 nM) and Olodaterol (1nM) alone or in combination, and of hemicholinium-3 (50 μM) on AChIL-17A, AChIL-22, AChRO…
In vitro anticholinergic drugs affect CD8+ peripheral blood T-cells apoptosis in COPD
2011
Novel pharmacological strategies are aimed at the resolution of systemic inflammation in COPD potentiating peripheral blood T-cell (PBT-cell) apoptosis. Although muscarinic acetylcholine receptors (mAChRs) M(3) and choline-acetyltransferase (ChAT) participate in the airway inflammation of COPD, their role in PBT-cell apoptosis remains unexplained. We evaluated in PBT-cells from COPD patients, smoker (S) and control (C) subjects: (1) apoptosis (by annexin V binding), (2) mAChR M(3) and ChAT expression, acetylcholine (ACh)-binding; (3) choline levels in serum and PBT-cells extracts. We tested the effects of Tiotropium (Spiriva(®)) and hemicholinium-3 (HCh-3) on apoptosis, NFκB pathway, caspas…
Functional role of cholinoceptors and purinoceptors in human isolated atrial and ventricular heart muscle
1989
1. The effects of cholinergic and purinergic stimulation on action potential, force of contraction and 86Rb efflux were investigated in human atrial and ventricular heart muscle. 2. In atrial heart muscle, carbachol and (-)-N6-(R-phenyl-isopropyl)-adenosine (R-PIA) and 5'-(N-ethyl)-carboxamido-adenosine (NECA) evoked transient decreases of action potential duration and force of contraction; the steady-state effects on force of contraction were virtually identical to control values. In the presence of propranolol, steady-state values after carbachol, R-PIA or NECA amounted to about 50% of control values. 3. In ventricular heart muscle, carbachol, NECA and R-PIA did not significantly affect t…
Acetylcholine release in the hippocampus of the urethane anaesthetised rat positively correlates with both peak theta frequency and relative power in…
2000
The need to achieve a clearer understanding of relations between hippocampal theta characteristics and cholinergic septohippocampal neuron activity, prompted us to re-examine, in the urethane-anaesthetised rat, the statistical relationships between the electrophysiological and neurochemical variables using a procedure which is believed to enhance significantly the degree of confidence with which parameters of theta recorded with classic macroelectrodes can be related to concomitant acetylcholine output measured by high-performance liquid chromatography with electrochemical detection. Firstly, the theta rhythm and the acetylcholine content were derived from the same hippocampus. Secondly, th…