China
Africa
Explore chapters and articles related to this topic
Cholinergic Agonists
Published in Sahab Uddin, Rashid Mamunur, Advances in Neuropharmacology, 2020
Rupali Patil, Aman Upaganlawar
Most contraindications to the use of muscarinic agonists are predictable consequences of mAChR stimulation and include asthma, chronic obstructive pulmonary disease, urinary or GI obstruction, acid-peptic disease, and cardiovascular disease accompanied by bradycardia, hypo-tension, and hyperthyroidism. Atrial fibrillation may be precipitated by muscarinic agonists in hyperthyroid patients (Brunton, 2011).
Parasympathomimetic Amines
Published in Kenneth J. Broadley, Autonomic Pharmacology, 2017
The parent muscarinic agonist, after which the receptor is named, is muscarine. It is isolated from the poisonous mushroom, Amanita muscaria, but the levels are insufficient to account for the toxicity of this fungus. The toxicity is attributed to anticholinergic and hallucinogenic isoxazole derivatives. Other richer sources of muscarine include species of Inocybe and Clitocybe, poisoning by which causes symptoms that may be predicted from the muscarinic agonist activity. These include salivation and lacrymation, nausea, vomiting and abdominal pain, diarrhoea, bronchospasm, hypotension and bradycardia (slow weak pulse) and visual disturbances. Muscarine is a quaternary ammonium compound that occurs naturally as the L-(+)-isomer and is highly selective for muscarinic receptors (Table 8.2).
Neurotransmitters and pharmacology
Published in Mark J. Ashley, David A. Hovda, Traumatic Brain Injury, 2017
Ronald A. Browning, Richard W. Clough
Muscarinic agonists include acetylcholine, which is not used systemically because it is rapidly destroyed by acetylcholinesterase or butyrylcholinesterase but is available for intraocular use (Miochol-E®); methacholine (Provocholine®), which is only partially sensitive to the action of acetylcholinesterase and is available as a diagnostic tool; bethanechol (Urecholine®), which is used for bowel and bladder hypofunction; carbachol (Isopto-Carbochol®), which is used to treat glaucoma and has some nicotinic agonist activity as well; and pilocarpine, a naturally occurring alkaloid found in plants, which is a potent muscarinic agonist used to treat glaucoma. Pilocarpine is given in eye drops applied topically to the eye or systemically for the treatment of xerostomia (Salagen®).
Outpatient pulmonary rehabilitation for severe asthma with fixed airway obstruction: Comparison with COPD
Published in Journal of Asthma, 2019
Agnès Bellocq, Wanda Gaspard, Camille Couffignal, Marie Vigan, Antoine Guerder, Julien Ambard, Sylvie Caruana, Thomas Similowski, Gilles Garcia, Camille Taillé
As expected, matched COPD patients differed from asthma patients by smoking status, allergy, and treatments. COPD patients were mostly heavy smokers or ex-smokers. COPD patients were more frequently prescribed long-acting muscarinic agonists than asthma patients; the use of other inhaled treatments did not significantly differ (Table 1). At the time of inclusion, bronchial reversibility was less frequent in COPD than asthma patients (14 vs 38%) (Table 2), even though all asthma patients had a positive bronchial dilation test documented in their file. Transfer alveolar-gas anomalies were more frequent in COPD than asthma patients (77% predicted [59–93] vs 65% predicted [55–73]; OR 1.1 [95% CI 1.0–1.1], p = 0.04) (Table 2) and rest and exercise hypoxemia was more pronounced, although not significantly (Table 2 and 3). These discrepancies between the two groups provide some evidence for distinct obstructive lung disease in the two groups. No data concerning blood or sputum eosinophilia were available in the database. Conversely, asthma and COPD patients did not differ in comorbidities; cardiovascular diseases were frequent in both groups (21 and 28%, respectively) (Table 1).
Update on novel antipsychotics and pharmacological strategies for treatment-resistant schizophrenia
Published in Expert Opinion on Pharmacotherapy, 2022
Andrea de Bartolomeis, Mariateresa Ciccarelli, Licia Vellucci, Michele Fornaro, Felice Iasevoli, Annarita Barone
The muscarinic receptor agonist xanomeline has antipsychotic properties despite dropping the D2R targeting entirely. It acts as an agonist specifically at central muscarinic M4 and M1 receptors (Ki = 79.4 nM and 20.0 nM respectively) [124]. To limit peripheral cholinergic AEs is co-administered with trospium chloride, which is a peripheral muscarinic antagonist not able to cross the BBB. Of interest, a decreased number of muscarinic M1 and M4 receptors has been found in post-mortem brain tissues collected from individuals with schizophrenia [125]. Several muscarinic agonists have been shown to exert a functional anti-dopaminergic effect, particularly in the ventral tegmental area, despite the lack of affinity for the dopamine receptors [126].
Sepsis impairs the propagation of cortical spreading depression in rats and this effect is prevented by antioxidant extract
Published in Nutritional Neuroscience, 2021
Mariana Séfora Bezerra Sousa, Danielle Viana de Souza Alves, Heloísa Mirelle Costa Monteiro, Dayane Aparecida Gomes, Eduardo Carvalho Lira, Angela Amancio-dos-Santos
Similarly, other conditions, well known to enhance oxidative stress, also promote the same effect. For instance, aging, a condition related to increase in levels of free radicals, has been shown to lead to a significant failure of CSD propagation [26]. Another report, using pilocarpine, also reinforces the suggested mechanism in our study [27]. Pilocarpine is a cholinergic muscarinic agonist that facilitates seizures. This drug promotes imbalance in neurotransmitter systems, especially the GABAergic and cholinergic ones, and can induce status epilepticus, which significantly increases oxidative stress in the rat cerebral cortex [28] and reduces CSD propagation [27].