ArticlePsychopharmacology2007
The muscarinic receptor antagonist tropicamide suppresses tremulous jaw movements in a rodent model of parkinsonian tremor: possible role of M4 receptors.
Article in Psychopharmacology, 2007. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 18 papers.
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Who cites it
18 citing papers in PubMed, 66 citations in OpenAlex.
- Sublingual Tropicamide Eye Drops for the Management of Clozapine-Induced Hypersalivation: A Case Series of Seven Patients.Pharmacy (Basel, Switzerland) · 2026Article
- Pharmacological Treatment of Tremor in Parkinson's Disease Revisited.Journal of Parkinson's disease · 2023Review
- Abuse of tropicamide eye drops: review of clinical data.Revista brasileira de psiquiatria (Sao Paulo, Brazil : 1999) · 2022Review
- Antimuscarinic Anticholinergic Medications in Parkinson Disease: To Prescribe or Deprescribe?Movement disorders clinical practice · 2021Review
- Inhibition of basal and amphetamine-stimulated extracellular signal-regulated kinase (ERK) phosphorylation in the rat forebrain by muscarinic acetylcholine M4 receptors.Brain research · 2018Article
- In Silico Studies Targeting G-protein Coupled Receptors for Drug Research Against Parkinson's Disease.Current neuropharmacology · 2018Article
- Effects of muscarinic receptor antagonists on cocaine discrimination in wild-type mice and in muscarinic receptor MBehavioural brain research · 2017Article
- Ganglionic GFAPJCI insight · 2017Article
- Involvement of Striatal Cholinergic Interneurons and M1 and M4 Muscarinic Receptors in Motor Symptoms of Parkinson's Disease.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2016Article
- Current Pharmaceutical Treatments and Alternative Therapies of Parkinson's Disease.Current neuropharmacology · 2016Review
- Development of allosteric modulators of GPCRs for treatment of CNS disorders.Neurobiology of disease · 2014Review
- Muscarinic receptors: their roles in disorders of the central nervous system and potential as therapeutic targets.CNS neuroscience & therapeutics · 2012Review
- Genetic reduction of muscarinic M4 receptor modulates analgesic response and acoustic startle response in a mouse model of fragile X syndrome (FXS).Behavioural brain research · 2012Article
- Pharmacological and physiological characterization of the tremulous jaw movement model of parkinsonian tremor: potential insights into the pathophysiology of tremor.Frontiers in systems neuroscience · 2011Article
- Acetylcholine-dopamine interactions in the pathophysiology and treatment of CNS disorders.CNS neuroscience & therapeutics · 2010Review
- A 5-HT2A receptor inverse agonist, ACP-103, reduces tremor in a rat model and levodopa-induced dyskinesias in a monkey model.Pharmacology, biochemistry, and behavior · 2008Article
- Dopamine/adenosine interactions related to locomotion and tremor in animal models: possible relevance to parkinsonism.Parkinsonism & related disorders · 2008Review
- Clozapine in Parkinsonian Rest Tremor: A Review of Outcomes, Adverse Reactions, and Possible Mechanisms of Action.Movement disorders clinical practiceReview
Corrections and comments
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Authors and funding
5 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
rationaleNonselective muscarinic acetylcholine antagonists have been used for several years as antiparkinsonian drugs. However, there are at least five subtypes of muscarinic receptor (M1-5). Neostriatal M4 receptors have been implicated in aspects of motor function, and it has been suggested that M4 antagonists could be used as treatments for parkinsonism.
objectiveCurrently, there is a lack of highly selective M4 antagonists that readily penetrate the blood brain barrier. Thus, the present studies focused upon the effects of tropicamide, a muscarinic acetylcholine receptor antagonist with moderate binding selectivity for the M4 receptor subtype. MATERIALS AND
methodsTremulous jaw movements were used as a model of parkinsonian tremor in these studies, and the effects of tropicamide were compared with those of the nonselective muscarinic antagonist atropine.
resultsTropicamide suppressed the tremulous jaw movements induced by the muscarinic agonist pilocarpine and the dopamine antagonist pimozide. Analysis of the dose-response curves indicated that tropicamide showed approximately the same potency as atropine for suppression of pilocarpine-induced jaw movements but was more potent than atropine on the suppression of pimozide-induced jaw movements. In contrast, atropine was more potent than tropicamide in terms of impairing performance on visual stimulus detection and delayed nonmatch-to-position tasks.
conclusionsThese studies demonstrate that tropicamide, which currently is used clinically for ophthalmic purposes, can exert actions that are consistent with antiparkinsonian effects. Moreover, the different pattern of effects shown by tropicamide compared to those of atropine on motor vs cognitive tasks could be due to the modest M4 selectivity shown by tropicamide.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.