Nomenclature: M2 receptor

Family: Acetylcholine receptors (muscarinic)

Annotation status:  image of a green circle Annotated and expert reviewed. Please contact us if you can help with updates. 

Contents

Gene and Protein Information
class A G protein-coupled receptor
Species TM AA Chromosomal Location Gene Symbol Gene Name Reference
Human 7 466 7q31-q35 CHRM2 cholinergic receptor, muscarinic 2 2,8-9,76,114
Mouse 7 466 6 B1 Chrm2 cholinergic receptor, muscarinic 2, cardiac 61
Rat 7 466 4q22 Chrm2 cholinergic receptor, muscarinic 2 96
Previous and Unofficial Names
m2
acetylcholine receptor, muscarinic 2
Acm2
7TM receptor
M2 muscarinic acetylcholine receptor
cholinergic receptor, muscarinic 2
cholinergic receptor, muscarinic 2, cardiac
muscarinic acetylcholine receptor M2
muscarinic receptor m2
AChR M2
muscarinic acetylcholine receptor 2
Chrm-2
Database Links
ChEMBL Target
DrugBank Target
Ensembl Gene
Entrez Gene
GPCRDB
GeneCards
GenitoUrinary Development Molecular Anatomy Project
HomoloGene
Human Protein Reference Database
InterPro
KEGG Gene
OMIM
PharmGKB Gene
PhosphoSitePlus
Protein Ontology (PRO)
RefSeq Nucleotide
RefSeq Protein
TreeFam
UniGene Hs.
UniProtKB
Wikipedia
Selected 3D Structures
Image of receptor 3D structure from RCSB PDB
Description:  Structure of the human M2 muscarinic acetylcholine receptor bound to an antagonist
PDB Id:  3UON
Ligand:  3-quinuclidinyl-benzilate
Resolution:  3.0Å
Species:  Human
References:  34
Image of receptor 3D structure from RCSB PDB
Description:  Structure of active human M2 muscarinic acetylcholine receptor bound to the agonist iperoxo
PDB Id:  4MQS
Ligand:  iperoxo
Resolution:  3.5Å
Species:  Human
References:  49
Image of receptor 3D structure from RCSB PDB
Description:  Structure of active human M2 muscarinic acetylcholine receptor bound to the agonist iperoxo and allosteric modulator LY2119620
PDB Id:  4MQT
Ligand:  LY2119620
Resolution:  3.7Å
Species:  Human
References:  49
Natural/Endogenous Ligand(s)
acetylcholine
Agonists
Key to terms and symbols View all chemical structures Click column headers to sort
Ligand Sp. Action Affinity Units Reference
NNC 11-1585 Hs Full agonist 10.1 pKi 19
pKi 10.1 [19]
NNC 11-1607 Hs Full agonist 8.2 pKi 19
pKi 8.2 [19]
pentylthio-TZTP Hs Full agonist 7.9 pKi 43
pKi 7.9 [43]
NNC 11-1314 Hs Full agonist 7.2 pKi 19
pKi 7.2 [19]
xanomeline Hs Full agonist 6.9 – 7.4 pKi 103,109
pKi 6.9 – 7.4 [103,109]
oxotremorine Rn Full agonist 6.5 pKi 48
pKi 6.5 [48]
acetylcholine Rn Full agonist 6.4 pKi 48
pKi 6.4 [48]
oxotremorine Hs Full agonist 5.0 – 6.6 pKi 43,48
pKi 5.0 – 6.6 [43,48]
arecaidine propargyl ester Hs Full agonist 5.7 pKi 43
pKi 5.7 [43]
carbachol Rn Full agonist 5.7 pKi 48
pKi 5.7 [48]
acetylcholine Hs Full agonist 4.3 – 6.5 pKi 18,43,48,53
pKi 4.3 – 6.5 [18,43,48,53]
McN-A-343 Rn Partial agonist 4.7 – 6.0 pKi 51
pKi 4.7 – 6.0 [51]
arecoline Hs Full agonist 5.2 pKi 43
pKi 5.2 [43]
carbachol Hs Full agonist 4.2 – 5.7 pKi 18,43,48
pKi 4.2 – 5.7 [18,43,48]
pilocarpine Hs Partial agonist 4.9 pKi 43
pKi 4.9 [43]
oxotremorine-M Hs Full agonist 4.9 pKi 43
pKi 4.9 [43]
methylfurmethide Hs Full agonist 4.9 pKi 43
pKi 4.9 [43]
furmethide Hs Full agonist 4.5 pKi 43
pKi 4.5 [43]
bethanechol Hs Full agonist 4.0 pKi 43
pKi 4.0 [43]
(+)aceclidine Hs Full agonist 6.2 – 6.4 pEC50 24,33
pEC50 6.2 – 6.4 [24,33]
(-)aceclidine Hs Partial agonist 5.6 – 5.7 pEC50 24,33
pEC50 5.6 – 5.7 [24,33]
View species-specific agonist tables
Agonist Comments
The binding data for McN-A-343 [51] is found on rat heart.
Please consult references [11,55,79,102,108] for further details of the activity of some of the ligands in this list.
Pilocarpine has been found to be a partial agonist [55,108] and a full agonist [102] at the M2 receptor.
Antagonists
Key to terms and symbols View all chemical structures Click column headers to sort
Ligand Sp. Action Affinity Units Reference
MT3 Hs Antagonist >6.3 pA2 73
pA2 >6.3 [73]
[3H]QNB Hs Antagonist 10.1 – 10.6 pKd 76
pKd 10.1 – 10.6 (Kd 2.51x10-11 – 7.94x10-11 M) [76]
[3H]clidinium Hs Antagonist 9.6 pKd 48
pKd 9.6 [48]
[3H]clidinium Rn Antagonist 9.5 pKd 48
pKd 9.5 [48]
[3H]N-methyl scopolamine Rn Antagonist 9.5 pKd 87
pKd 9.5 [87]
[3H]4NMPB Rn Antagonist 9.4 pKd 87
pKd 9.4 [87]
[3H]AF DX-384 Hs Antagonist 8.7 pKd 68
pKd 8.7 [68]
biperiden Hs Antagonist 8.2 pKd 7
pKd 8.2 (Kd 6.3x10-9 M) [7]
[3H]N-methyl scopolamine Hs Antagonist 6.3 – 9.9 pKd 16,18,37,43-45,47,53,102
pKd 6.3 – 9.9 (Kd 1.25x10-10 – 5.01x10-7 M) [16,18,37,43-45,47,53,102]
tripitramine Hs Antagonist 9.6 pKi 60
pKi 9.6 [60]
propantheline Hs Antagonist 9.5 pKi 39
pKi 9.5 [39]
atropine Rn Antagonist 9.0 – 9.1 pKi 46,48
pKi 9.0 – 9.1 [46,48]
dexetimide Hs Antagonist 8.9 pKi 48
pKi 8.9 [48]
ipratropium Hs Antagonist 8.8 pKi 37
pKi 8.8 [37]
dexetimide Rn Antagonist 8.8 pKi 48
pKi 8.8 [48]
scopolamine Hs Antagonist 8.7 pKi 39
pKi 8.7 [39]
SCH 57790 Hs Antagonist 8.6 pKi 50
pKi 8.6 [50]
tolterodine Hs Inverse agonist 8.6 pKi 71
pKi 8.6 [71]
atropine Hs Antagonist 7.8 – 9.2 pKi 12,18,37,39,48,71,76
pKi 7.8 – 9.2 [12,18,37,39,48,71,76]
4-DAMP Hs Antagonist 8.3 pKi 48
pKi 8.3 [48]
AFDX384 Hs Antagonist 8.2 pKi 22
pKi 8.2 [22]
4-DAMP Rn Antagonist 8.2 pKi 46,48
pKi 8.2 [46,48]
himbacine Hs Antagonist 7.9 – 8.4 pKi 45,48,67
pKi 7.9 – 8.4 [45,48,67]
himbacine Rn Antagonist 7.9 pKi 48
pKi 7.9 [48]
methoctramine Hs Antagonist 7.3 – 8.4 pKi 12,26,48,71
pKi 7.3 – 8.4 [12,26,48,71]
oxybutynin Hs Inverse agonist 7.7 pKi 71
pKi 7.7 [71]
hexocyclium Hs Antagonist 7.6 pKi 12
pKi 7.6 [12]
silahexocyclium Hs Antagonist 7.5 pKi 12
pKi 7.5 [12]
darifenacin Hs Inverse agonist 7.3 – 7.6 pKi 37,71
pKi 7.3 – 7.6 [37,71]
methoctramine Rn Antagonist 7.3 pKi 48
pKi 7.3 [48]
otenzepad Hs Antagonist 6.7 – 7.3 pKi 12,26,48
pKi 6.7 – 7.3 [12,26,48]
imipramine Hs Antagonist 6.9 pKi 48
pKi 6.9 [48]
HHSiD Rn Antagonist 6.7 – 6.8 pKi 46,48
pKi 6.7 – 6.8 [46,48]
hexahydrodifenidol Hs Antagonist 6.7 pKi 12
pKi 6.7 [12]
HHSiD Hs Antagonist 6.6 – 6.8 pKi 12,26,48
pKi 6.6 – 6.8 [12,26,48]
dicyclomine Hs Antagonist 6.6 pKi 12
pKi 6.6 [12]
pirenzepine Rn Antagonist 5.3 – 7.4 pKi 46,48,87
pKi 5.3 – 7.4 [46,48,87]
p-F-HHSiD Hs Antagonist 6.1 – 6.6 pKi 26,39
pKi 6.1 – 6.6 [26,39]
VU0255035 Hs Antagonist 6.2 pKi 85
pKi 6.2 [85]
MT3 Hs Antagonist <6.0 pKi 45
pKi <6.0 [45]
otenzepad Rn Antagonist 4.6 – 7.3 pKi 46,48,87
pKi 4.6 – 7.3 [46,48,87]
gallamine Hs Antagonist 5.8 pKi 48
pKi 5.8 [48]
pirenzepine Hs Antagonist 4.9 – 6.4 pKi 12,26,39,45,48,71,76
pKi 4.9 – 6.4 [12,26,39,45,48,71,76]
gallamine Rn Antagonist 5.6 pKi 48
pKi 5.6 [48]
lithocholylcholine Hs Antagonist 5.4 pKi 18
pKi 5.4 [18]
guanylpirenzepine Rn Antagonist 5.3 pKi 101
pKi 5.3 [101]
levetimide Hs Antagonist 5.0 pKi 48
pKi 5.0 [48]
levetimide Rn Antagonist 4.8 pKi 48
pKi 4.8 [48]
View species-specific antagonist tables
Antagonist Comments
Dexetimide is the optical isomer of levetimide [48].

Biperiden is an approved drug antagonist of muscarinic acetylcholine receptors. We have tagged the M1 subtype as the drug's primary target as affinity is 10-fold higher at this receptor subtype [7].
Allosteric Regulators
Key to terms and symbols View all chemical structures Click column headers to sort
Ligand Sp. Action Affinity Units Reference
alcuronium Hs Neutral 6.1 – 6.9 pKd 43,95
pKd 6.1 – 6.9 [43,95]
WIN 51,708 Hs Negative 5.9 pKd 58
pKd 5.9 [58]
KT 5823 Hs Positive 5.7 pKd 57
pKd 5.7 [57]
WIN 62,577 Hs Negative 5.3 pKd 58
pKd 5.3 [58]
staurosporine Hs Positive 5.1 pKd 57
pKd 5.1 [57]
vincamine Hs Neutral 5.1 pKd 43
pKd 5.1 [43]
Gö 7874 Hs Negative 5.0 pKd 57
pKd 5.0 [57]
strychnine Hs Positive 4.9 – 5.0 pKd 43,53,95
pKd 4.9 – 5.0 [43,53,95]
N-benzyl brucine Hs Negative 4.8 pKd 56
pKd 4.8 [56]
N-benzyl brucine Hs Positive 4.8 pKd 56
pKd 4.8 [56]
N-chloromethyl-brucine Hs Negative 4.6 pKd 56
pKd 4.6 [56]
N-chloromethyl-brucine Hs Positive 4.6 pKd 56
pKd 4.6 [56]
brucine Hs Positive 4.3 – 4.6 pKd 43,56
pKd 4.3 – 4.6 [43,56]
brucine Hs Negative 4.3 pKd 56
pKd 4.3 [56]
eburnamonine Hs Neutral 4.2 pKd 43
pKd 4.2 [43]
thiochrome Hs Neutral 3.9 pKd 54
pKd 3.9 [54]
brucine N-oxide Hs Negative 3.5 pKd 56
pKd 3.5 [56]
brucine N-oxide Hs Positive 3.5 pKd 56
pKd 3.5 [56]
[3H]dimethyl-W84 Hs Positive 8.5 pKi 95
pKi 8.5 [95]
dimethyl-W84 Hs Positive 8.5 pKi 95
pKi 8.5 [95]
W-84 Hs Positive 7.6 pKi 95
pKi 7.6 [95]
WDuo3 Hs Positive 6.9 pKi 95
pKi 6.9 [95]
gallamine Hs Negative 5.8 – 7.6 pKi 48,95
pKi 5.8 – 7.6 [48,95]
gallamine Rn Negative 5.6 pKi 48
pKi 5.6 [48]
View species-specific allosteric regulator tables
Primary Transduction Mechanisms
Transducer Effector/Response
Gi/Go family Adenylate cyclase inhibition
References:  66,75
Secondary Transduction Mechanisms
Transducer Effector/Response
Gs family
Gq/G11 family
Adenylate cyclase stimulation
Phospholipase C stimulation
References:  33,65
Tissue Distribution
Esophageal smooth muscle.
Species:  Human
Technique:  Radioligand binding.
References:  77
Bladder.
Species:  Human
Technique:  RT-PCR.
References:  97
Ciliary muscle.
Species:  Human
Technique:  In situ hybridisation and Northern blotting.
References:  113
Vestibular system.
Species:  Human
Technique:  RT-PCR.
References:  100
CNS: cerebral cortex, thalamus, brainstem, medulla, hypothalamus.
Species:  Human
Technique:  Radioligand binding.
References:  20
CNS: cerebral cortex, corpus striatum, hippocampus, thalamus, hypothalamus, midbrain, pons-medulla, cerebellum, spinal cord.
Species:  Mouse
Technique:  Radioligand binding.
References:  72
CNS: forebrain.
Species:  Mouse
Technique:  immunocytochemistry.
References:  38
Salivary gland: submandibular ganglion.
Species:  Rat
Technique:  Immunohistochemistry.
References:  86
Intestinal smooth muscle.
Species:  Rat
Technique:  Radioligand binding.
References:  15
Vestibular system.
Species:  Rat
Technique:  RT-PCR.
References:  100
CNS: hippocampus.
Species:  Rat
Technique:  immunocytochemistry.
References:  59
CNS: basal forebrain, parabigeminal nucleus, pedunculopontine and laterodorsal tegmental nuclei, cranial nerve nuclei.
Species:  Rat
Technique:  in situ hybridisation.
References:  99
CNS: cerebral cortex, hipocampus, corpus striatum, olfactory tubercle, midbrain, pons-medulla, cerebellum.
Species:  Rat
Technique:  Immunoprecipitation.
References:  110
CNS: caudate putamen.
Species:  Rat
Technique:  in situ hybridisation.
References:  104
CNS: pons.
Species:  Rat
Technique:  Radioligand binding.
References:  3
Heart: intrinsic neurons.
Species:  Rat
Technique:  in situ hybridisation.
References:  36
Expression Datasets

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Log average relative transcript abundance in mouse tissues measured by qPCR from Regard, J.B., Sato, I.T., and Coughlin, S.R. (2008). Anatomical profiling of G protein-coupled receptor expression. Cell, 135(3): 561-71. [PMID:18984166] [Raw data: website]

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Functional Assays
Measurement of cAMP levels in CHO cells transfected with the human M2 receptor.
Species:  Human
Tissue:  CHO cells.
Response measured:  Inhibition of cAMP accumulation.
References:  16,18-19,79
Measurement of cAMP levels in mouse Y1 adrenal cells transfected with the mouse M2 receptor.
Species:  Mouse
Tissue:  Y1 adrenal cells.
Response measured:  Inhibition of cAMP accumulation.
References:  84
Measurement of cAMP levels in JEG-3 cells transfected with the human M2 receptor, using a cAMP response element (CRE)-coupled luciferase construct as the reporter.
Species:  Human
Tissue:  JEG-3 cells.
Response measured:  Inhibition of cAMP accumulation.
References:  66
Measurement of cAMP levels in dissociated rat cortical tissue endogenously expressing the M2 receptor.
Species:  Rat
Tissue:  Cortical tissue.
Response measured:  Inhibition of cAMP accumulation.
References:  1
Measurement of ERK1/2 activity in COS-7 cells transfected with the human M2 receptor.
Species:  Human
Tissue:  COS-7 cells.
Response measured:  Increase in ERK1/2 activity.
References:  80
Measurement of GIRK channel activity in Xenopus oocytes transfected with the human M2 receptor.
Species:  Human
Tissue:  Xenopus oocytes.
Response measured:  Activation of GIRK channels.
References:  111
Measurement of GIRK channel activity in rat superior cervical ganglion neurons endogenously expressing the M2 receptor.
Species:  Rat
Tissue:  Superior cervical ganglion neurons.
Response measured:  Activation of GIRK channels.
References:  28-29
Measurement of AC activity in rat myocardial homogenates endogenously expressing the M2 receptor.
Species:  Rat
Tissue:  Myocardial homogenates.
Response measured:  Inhibition of AC activity.
References:  25
Measurement of the effects of a ligand on the level, or rate, of binding of GTPγ35S to membranes.
Species:  Human
Tissue:  CHO cells.
Response measured:  The binding of GTPγ35S to G proteins coupled to the receptor.
References:  5,52-55,57-58
Measurement of the effects of a ligand on the rate of hydrolysis of GTP by G proteins in membranes.
Species:  Human
Tissue:  CHO cell membranes.
Response measured:  Generation of 32Pi from [γ-32P]GTP.
References:  55
Physiological Functions
Vasodilation.
Species:  Rat
Tissue:  Pulmonary artery.
References:  64
Mediation of colonic motor responses to eating.
Species:  Human
Tissue:  In vivo.
References:  70
Hypertension.
Species:  Rat
Tissue:  In vivo.
References:  74
Stimulation of pancreatic secretion.
Species:  Rat
Tissue:  In vivo.
References:  17
Stimulation of water consumption.
Species:  Rat
Tissue:  In vivo.
References:  35
Control of small intestinal motility.
Species:  Rat
Tissue:  In vivo.
References:  27
Hypotension.
Species:  Rat
Tissue:  In vivo.
References:  91
Bradycardia.
Species:  Rat
Tissue:  In vivo.
References:  91
Thermal automodulator.
Species:  Rat
Tissue:  In vivo.
References:  83
Autoreceptor: modulation of ACh release.
Species:  Human
Tissue:  Bronchi.
References:  69,93
Stimulation of histamine release.
Species:  Rat
Tissue:  Stomach.
References:  81
Spinal analgesia.
Species:  Rat
Tissue:  In vivo.
References:  31
Autoreceptor: modulation of ACh release.
Species:  Rat
Tissue:  Heart.
References:  6
Locomotor activity.
Species:  Rat
Tissue:  In vivo.
References:  10
Modulation of the sleep-wake cycle.
Species:  Rat
Tissue:  In vivo.
References:  40-42
Physiological Consequences of Altering Gene Expression
Atrial preparations from M2 receptor knockout mice do not exhibit agonist-induced bradycardia as seen in wild-type atrial preparations.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  13,32,89
M2 receptor knockout mice do not exhibit agonist-induced tremor as seen in wild-type mice.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  32
M2 receptor knockout mice exhibit reduced agonist-induced hypothermia as compared to wild-type mice.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  32
M2 receptor knockout mice exhibit reduced agonist-induced antinociception compared to wild-type mice.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  21,32
Smooth muscle preparations (stomach fundus, urinary bladder, trachea, gallbladder) from M2 receptor knockout mice exhibit reduced agonist-induced contractions compared to wild-type mice.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  13,88-89
Hippocampal, cortical and striatal brain slices from M2/M4 double knockout mice lack muscarinic agonist-induced inhibition of acetylcholine release that is seen with wild-type brain slices.
From M2 receptor single knockout mice, the hippocampal and cortical slices exhibit this loss of inhibition of acetylcholine release, but the inhibition remains in the striatal slices.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  112
Skin preparations from M2 receptor knockout mice no longer show muscarinic-induced desensitisation of peripheral nociception.
In addition, the heat-induced release of CGRP which is inhibited by muscarine in wild-type mice is unaltered in M2 knockout mice.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  4
Tissue from atria, bladder and vas deferens of M2 receptor knockout mice exhibit reduced agonist-induced inhibition of noradrenaline release compared to wild-type mice.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  94
Smooth muscle preparations (ileum, trachea, urinary bladder) from M2 receptor knockout mice exhibit increased relaxant effects of forskolin and isoproterenol against agonist-induced contractions.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  23,62
M2 receptor knockout mice exhibit a reduced muscarinic antagonist-induced increase in hippocampal acetylcholine release compared to wild-type mice.
M2/M4 double knockout mice completely lack this response.
In addition, M2 and M2/M4 knockout mice exhibit an increase in hippocampal acetylcholine release in response to a novel environment.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  98
Lung slices from M2 receptor knockout mice exhibit reduced agonist-induced bronchoconstriction compared to wild-type mice.
This bronchoconstriction is completely abolished in M2/M3 double knockout mice.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  90
M2 receptor knockout mice do not exhibit agonist-induced or vagally-stimulated bradycardia in vivo as seen in wild-type mice.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  30
M2 receptor knockout mice exhibit increased agonist-induced or vagally-stimulated bronchoconstriction in vivo compared to wild-type mice.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  30
M2 receptor knockout mice exhibit impaired behavioural flexibility, working memory and hippocampal plasticity.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  82
M2 receptor knockout mice exhibit increased agonist/stress-induced pituitary-adrenal responses.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  78
Smooth muscle from the small intestine of M2 receptor knockout mice do not exhibit any alteration in EFS-induced acetylcholine release.
However, M2/M4 double knockout mice exhibit an increase in acetylcholine release.
Overall, it is thought that both M2 and M4 receptors mediate the autoinhibitory control of acetylcholine release in the mouse ileum, and that each can compensate for loss of the other.
Species:  Mouse
Tissue: 
Technique:  Gene targeting in embryonic stem cells.
References:  92
Phenotypes, Alleles and Disease Models Mouse data from MGI

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Allele Composition & genetic background Accession Phenotype Id Phenotype Reference
Chrm2tm1Jwe|Chrm4tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe,Chrm4tm1Jwe/Chrm4tm1Jwe
involves: 129S4/SvJae * 129S6/SvEvTac * CF-1
MGI:88397  MGI:88399  MP:0004994 abnormal brain wave pattern PMID: 16110248 
Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe
involves: 129S4/SvJae * CF-1
MGI:88397  MP:0002206 abnormal CNS synaptic transmission PMID: 15919709 
Chrm2tm1Jwe|Chrm4tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe,Chrm4tm1Jwe/Chrm4tm1Jwe
involves: 129S4/SvJae * 129S6/SvEvTac * CF-1
MGI:88397  MGI:88399  MP:0002206 abnormal CNS synaptic transmission PMID: 15919709 
Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe
involves: 129S4/SvJae * CF-1
MGI:88397  MP:0005085 abnormal gallbladder physiology PMID: 11961069 
Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe
involves: 129S4/SvJae * CF-1
MGI:88397  MP:0001629 abnormal heart rate PMID: 10688600 
Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe
B6.129S4-Chrm2
MGI:88397  MP:0002566 abnormal sexual interaction PMID: 18382674 
Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe
B6.129S4-Chrm2
MGI:88397  MP:0001529 abnormal vocalization PMID: 18382674 
Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe
involves: 129S4/SvJae * CF-1
MGI:88397  MP:0001945 bronchoconstriction PMID: 14645675 
Chrm2tm1Jwe|Chrm3tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe,Chrm3tm1Jwe/Chrm3tm1Jwe
involves: 129S4/SvJae * 129S6/SvEvTac * CF-1
MGI:88397  MGI:88398  MP:0001945 bronchoconstriction PMID: 14645675 
Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe
involves: 129S4/SvJae * CF-1
MGI:88397  MP:0001262 decreased body weight PMID: 9990086 
Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe
involves: 129S4/SvJae * CF-1
MGI:88397  MP:0001982 decreased chemically-elicited antinociception PMID: 9990086 
Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe
involves: 129S4/SvJae * CF-1
MGI:88397  MP:0008874 decreased physiological sensitivity to xenobiotic PMID: 9990086 
Chrm2+|Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2+
involves: 129S4/SvJae * CF-1
MGI:88397  MP:0008874 decreased physiological sensitivity to xenobiotic PMID: 9990086 
Chrm2tm1Minm|Chrm3tm1Mmt Chrm2tm1Minm/Chrm2tm1Minm,Chrm3tm1Mmt/Chrm3tm1Mmt
involves: 129X1/SvJ * C57BL/6
MGI:88397  MGI:88398  MP:0000539 distended urinary bladder PMID: 12486155 
Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe
involves: 129S4/SvJae * CF-1
MGI:88397  MP:0009747 impaired behavioral response to xenobiotic PMID: 10688600 
Chrm2+|Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2+
involves: 129S4/SvJae * CF-1
MGI:88397  MP:0009747 impaired behavioral response to xenobiotic PMID: 9990086 
Chrm2tm1Minm|Chrm3tm1Mmt Chrm2tm1Minm/Chrm2tm1Minm,Chrm3tm1Mmt/Chrm3tm1Mmt
involves: 129X1/SvJ * C57BL/6
MGI:88397  MGI:88398  MP:0000742 impaired contractility of ileal smooth muscle PMID: 12486155 
Chrm2tm1Jwe Chrm2tm1Jwe/Chrm2tm1Jwe
involves: 129S4/SvJae * CF-1
MGI:88397  MP:0000740 impaired smooth muscle contractility PMID: 10688600  11961069 
Chrm2tm1Minm|Chrm3tm1Mmt Chrm2tm1Minm/Chrm2tm1Minm,Chrm3tm1Mmt/Chrm3tm1Mmt
involves: 129X1/SvJ * C57BL/6
MGI:88397  MGI:88398  MP:0000740 impaired smooth muscle contractility PMID: 12486155 
Chrm2tm1Minm|Chrm3tm1Mmt Chrm2tm1Minm/Chrm2tm1Minm,Chrm3tm1Mmt/Chrm3tm1Mmt
involves: 129X1/SvJ * C57BL/6
MGI:88397  MGI:88398  MP:0002546 mydriasis PMID: 12486155 
Chrm2tm1Minm|Chrm3tm1Mmt Chrm2tm1Minm/Chrm2tm1Minm,Chrm3tm1Mmt/Chrm3tm1Mmt
involves: 129X1/SvJ * C57BL/6
MGI:88397  MGI:88398  MP:0001732 postnatal growth retardation PMID: 12486155 
Clinically-Relevant Mutations and Pathophysiology
Disease:  Alcohol dependence
OMIM:  103780
References: 
Mutations not determined
General Comments
For reviews on muscarinic receptor knockout mice see [14,63,105-107].
Available Assays
DiscoveRx PathHunter® CHO-K1 CHRM2 β-Arrestin Cell Line (Cat no. 93-0198C2)
PathHunter® eXpress CHRM2 CHO-K1 β-Arrestin GPCR Assay (Cat no. 93-0198E2CP0M)
more info

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