Evidence map›Paper›PMID 22610522›Full record

ArticlePsychopharmacology2012

LY2033298, a positive allosteric modulator at muscarinic M₄ receptors, enhances inhibition by oxotremorine of light-induced phase shifts in hamster circadian activity rhythms.

Robert L Gannon, Mark J Millan

Abstract read
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In one paragraph

Article in Psychopharmacology, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed
0.4field-weighted citation impact, top 46% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

5 citing papers in PubMed, 13 citations in OpenAlex.

  1. Striatal MFrontiers in pharmacology · 2025
    Article
  2. Article
  3. Article
  4. Lack of MBrain structure & function · 2020
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  5. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

2 authors at 2 institutions in 2 countries.

Robert L GannonDepartment of Biology, Valdosta State University, Valdosta, GA, 31602, USA. rlgannon@valdosta.edu
Mark J Millan
AVL (France) · FRValdosta State University · US

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

rationaleEntrainment of circadian rhythms to the light-dark cycle is essential for restorative sleep, and abnormal sleep timing is implicated in central nervous system (CNS) disorders like depression, schizophrenia, and Alzheimer's disease. Many transmitters, including acetylcholine, that exerts its actions via muscarinic receptors modulate the suprachiasmatic nucleus, the master pacemaker.

objectivesSince positive allosteric modulators of muscarinic M(4) receptors are candidates for treatment of mood and cognitive deficits of CNS disorders, it is important to evaluate their circadian actions. MATERIALS AND

methodsThe effects of intraperitoneally applied muscarinic agents on circadian wheel-running rhythms were measured employing hamsters, a model organism for studying activity rhythms.

resultsSystemic administration of the muscarinic receptor agonist oxotremorine (0.01-0.04 mg/kg) inhibited light-induced phase delays and advances of hamster circadian wheel-running rhythms. The M₄ positive allosteric modulator, LY2033298 (10-40 mg/kg), had no effect on light-induced phase shifts when administered alone, yet significantly enhanced (at 20 mg/kg) the inhibitory influence of oxotremorine on light-induced phase delays. In addition, the muscarinic receptor antagonist, scopolamine, which was without effect on light-induced phase shifts when administered alone (0.001-0.1 mg/kg), antagonized (at 0.1 mg/kg) the inhibitory effect of oxotremorine and LY2033298 on light-induced phase delays.

conclusionsThese results are the first to demonstrate that systemically applied muscarinic receptor agonists modulate circadian activity rhythms, and they also reveal a specific role for M₄ receptors. It will be of importance to evaluate circadian actions of psychotropic drugs acting via M₄ receptors, since they may display beneficial properties under pathological conditions.

Indexed as

AnimalsCircadian RhythmCricetinaeDose-Response Relationship, DrugLightMaleMotor ActivityMuscarinic AgonistsMuscarinic AntagonistsNicotinic AcidsOxotremorineReceptor, Muscarinic M4ScopolamineThiophenes3-amino-5-chloro-6-methoxy-4-methyl-thieno(2,3-b)pyridine-2-carboxylic acid cyclopropylamideMuscarinic AgonistsMuscarinic AntagonistsNicotinic AcidsOxotremorineReceptor, Muscarinic M4ScopolamineThiophenes

Identifiers

PMID22610522
OpenAlexW2068286049

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

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.