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KCa1.1

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Not curated in GtoImmuPdb

Target id: 380

Nomenclature: KCa1.1

Family: Calcium- and sodium-activated potassium channels (KCa, KNa)

Annotation status:  image of a blue circle Annotated and reviewed, awaiting update  » Email us

Gene and Protein Information Click here for help
Species TM P Loops AA Chromosomal Location Gene Symbol Gene Name Reference
Human 7 1 1236 10q22.3 KCNMA1 potassium calcium-activated channel subfamily M alpha 1 44
Mouse 7 1 1209 14 A3 Kcnma1 potassium large conductance calcium-activated channel, subfamily M, alpha member 1
Rat 7 1 1209 15p16 Kcnma1 potassium calcium-activated channel subfamily M alpha 1
Previous and Unofficial Names Click here for help
BK channel | BK channel alpha subunit | calcium-activated potassium channel alpha subunit | maxi K+ channel | maxi K channel | potassium channel, calcium activated large conductance subfamily M alpha, member 1 | potassium large conductance calcium-activated channel | slo-alpha | slowpoke homolog
Database Links Click here for help
Alphafold
ChEMBL Target
DrugBank Target
Ensembl Gene
Entrez Gene
Human Protein Atlas
KEGG Gene
OMIM
Orphanet
Pharos
RefSeq Nucleotide
RefSeq Protein
UniProtKB
Wikipedia
Selected 3D Structures Click here for help
Image of receptor 3D structure from RCSB PDB
Description:  Ca2+ bound open-inactivated hSlo1 + beta2N-beta4 channel in detergent-conformation 2 of inactivating domain
PDB Id:  9D18
Ligand:  Ca2+
Resolution:  2.88Å
Species:  Human
References:  1
Image of receptor 3D structure from RCSB PDB
Description:  Ca2+ bound open-inactivated hSlo1 + beta2N-beta4 channel in detergent-conformation 3 of inactivating domain
PDB Id:  9D19
Ligand:  Ca2+
Resolution:  2.88Å
Species:  Human
References:  1
Image of receptor 3D structure from RCSB PDB
Description:  Ca2+ bound open-inactivated hSlo1 + beta2N-beta4 channel in nanodisc
PDB Id:  9CZM
Ligand:  Ca2+
Resolution:  2.57Å
Species:  Human
References:  1
Image of receptor 3D structure from RCSB PDB
Description:  Ca2+ bound intermediate state of hSlo1 + beta2N-beta4 channel in nanodisc
PDB Id:  9CZO
Ligand:  Ca2+
Resolution:  2.87Å
Species:  Human
References:  1
Image of receptor 3D structure from RCSB PDB
Description:  Ca2+ free hSlo1 + beta2N-beta4 channel in nanodisc
PDB Id:  9CZK
Resolution:  3.5Å
Species:  Human
References:  1
Image of receptor 3D structure from RCSB PDB
Description:  Ca2+ free hSlo1 + beta2N-beta4 channel in detergent
PDB Id:  9CZJ
Resolution:  3.54Å
Species:  Human
References:  1
Image of receptor 3D structure from RCSB PDB
Description:  Ca2+ bound intermediate state of hSlo1 + beta2N-beta4 channel in detergent
PDB Id:  9CZH
Ligand:  Ca2+
Resolution:  2.8Å
Species:  Human
References:  1
Image of receptor 3D structure from RCSB PDB
Description:  Structure of human Slo1 and human LRRC26 in EDTA - LRRD masked
PDB Id:  8VAZ
Resolution:  2.82Å
Species:  Human
References: 
Image of receptor 3D structure from RCSB PDB
Description:  Human Slo1 - human LRRC26 in presence of EDTA - GR masked
PDB Id:  8VAV
Resolution:  3.13Å
Species:  Human
References: 
Image of receptor 3D structure from RCSB PDB
Description:  Cryo-EM structure of RCK1 mutated human Slo1-LRRC26 complex
PDB Id:  7YO1
Resolution:  3.6Å
Species:  Human
References:  55
Image of receptor 3D structure from RCSB PDB
Description:  Cryo-EM structure of human Slo1-LRRC26 complex with Symmetry Expansion
PDB Id:  7YO0
Resolution:  3.6Å
Species:  Human
References:  55
Image of receptor 3D structure from RCSB PDB
Description:  Cryo-EM structure of human Slo1-LRRC26 complex with C1 symmetry
PDB Id:  7YNZ
Resolution:  3.5Å
Species:  Human
References:  55
Image of receptor 3D structure from RCSB PDB
Description:  Cryo-EM structure of human Slo1-LRRC26 complex with C4 symmetry
PDB Id:  7YO3
Resolution:  3.1Å
Species:  Human
References:  55
Image of receptor 3D structure from RCSB PDB
Description:  Cryo-EM structure of hSlo1 in total membrane vesicles
PDB Id:  8GH9
Resolution:  3.8Å
Species:  Human
References:  41
Image of receptor 3D structure from RCSB PDB
Description:  Cryo-EM structure of hSlo1 in digitonin, Ca2+-free and EDTA-free
PDB Id:  8GHG
Resolution:  3.3Å
Species:  Human
References:  41
Image of receptor 3D structure from RCSB PDB
Description:  Cryo-EM structure of hSlo1 in plasma membrane vesicles
PDB Id:  8GHF
Resolution:  2.7Å
Species:  Human
References:  41
Image of receptor 3D structure from RCSB PDB
Description:  Human BK channel reconstituted into liposomes
PDB Id:  6ND0
Resolution:  3.5Å
Species:  Human
References:  43
Image of receptor 3D structure from RCSB PDB
Description:  Cryo-EM structure of Ca2+-bound hsSlo1 channel
PDB Id:  6V38
Ligand:  Ca2+
Resolution:  3.8Å
Species:  Human
References:  40
Image of receptor 3D structure from RCSB PDB
Description:  Cryo-EM structure of Ca2+-bound hsSlo1-beta4 channel complex
PDB Id:  6V22
Ligand:  Ca2+
Resolution:  3.2Å
Species:  Human
References:  40
Image of receptor 3D structure from RCSB PDB
Description:  Cryo-EM structure of Ca2+-free hsSlo1-beta4 channel complex
PDB Id:  6V35
Resolution:  3.5Å
Species:  Human
References:  40
Associated Proteins Click here for help
Heteromeric Pore-forming Subunits
Name References
Slack 19
Auxiliary Subunits
Name References
β1 - β4 6,18,50
γ1 - γ4 56-57
Other Associated Proteins
Name References
β2-adrenoceptor 23
Functional Characteristics Click here for help
Maxi KCa
Ion Selectivity and Conductance Click here for help
Species:  Human
Rank order:  K+ [200.0 - 220.0 pS]
References:  26,44
Species:  Mouse
Rank order:  K+ [272.0 pS]
References:  7,49

Download all structure-activity data for this target as a CSV file go icon to follow link

Activators
Key to terms and symbols View all chemical structures Click column headers to sort
Ligand Sp. Action Value Parameter Concentration range (M) Holding voltage (mV) Reference
dehydrosoyasaponin I Small molecule or natural product Hs - ~7.0 pEC50 - - 15
pEC50 ~7.0 (EC50 ~1x10-7 M) [15]
16,17-EpDPE Small molecule or natural product Hs - 6.6 pEC50 - - 48
pEC50 6.6 (EC50 2.3x10-7 M) [48]
GoSlo-SR-5-69 Small molecule or natural product Hs - 6.6 pEC50 - - 36
pEC50 6.6 (EC50 2.5x10-7 M) [36]
flindokalner Small molecule or natural product Click here for species-specific activity table Hs - 6.4 – 6.5 pEC50 - -100.0 16-17
pEC50 6.5 [16]
Holding voltage: -100.0 mV
pEC50 6.4 – 6.5 (EC50 4x10-7 – 3x10-7 M) [17]
magnolol Small molecule or natural product Click here for species-specific activity table Ligand has a PDB structure Hs - ~6.0 pEC50 - - 52
pEC50 ~6.0 (EC50 ~1x10-6 M) [52]
17β-estradiol Small molecule or natural product Approved drug Click here for species-specific activity table Ligand has a PDB structure Hs - 5.6 pEC50 - - 45
pEC50 5.6 [45]
BMS-191011 Small molecule or natural product Hs - ~5.6 pEC50 - - 34
pEC50 ~5.6 (EC50 ~2.5x10-6 M) [34]
BC5 Small molecule or natural product Hs - 5.6 pEC50 - - 61
pEC50 5.6 (EC50 2.5x10-6 M) [61]
NS11021 Small molecule or natural product Hs - 4.7 – 6.4 pEC50 - - 4
pEC50 6.4 (EC50 4x10-7 M) [4]
pEC50 4.7 – 5.0 (EC50 2x10-5 – 1x10-5 M) [4]
NS1643 Small molecule or natural product Click here for species-specific activity table Hs Agonist 5.2 – 5.7 pEC50 - -150.0 38
pEC50 5.2 – 5.7 [38]
Holding voltage: -150.0 mV
NS1619 Small molecule or natural product Click here for species-specific activity table Hs - 5.4 pEC50 - - 21,31
pEC50 5.4 (EC50 3.6x10-6 M) [21,31]
NS19504 Small molecule or natural product Ligand has a PDB structure Hs - 5.0 pEC50 - - 28
pEC50 5.0 (EC50 1.1x10-5 M) [28]
NS004 Small molecule or natural product Click here for species-specific activity table Hs - 4.5 – 5.0 pEC50 - -
pEC50 4.5 – 5.0 (EC50 3x10-5 – 1x10-5 M)
NS1619 Small molecule or natural product Rn - 4.5 pEC50 - - 21
pEC50 4.5 (EC50 3.2x10-5 M) [21]
Description: Determined in rat cortical neurones
mefenamic acid Small molecule or natural product Approved drug Click here for species-specific activity table Ligand has a PDB structure Immunopharmacology Ligand Hs - 4.0 pEC50 - - 42
pEC50 4.0 (EC50 1x10-4 M) [42]
View species-specific activator tables
Activator Comments
Mg2+ has also been reported as an activator for the KCa1.1
Progesterone activates channels through binding β1/β4 auxiliary subunits (EC50 ~1-2 μM) [29].
17β-estradiol and tamoxifen activate channels with β1 auxiliary subunits (EC50 1-10 μM) [10].
Channel Blockers
Key to terms and symbols View all chemical structures Click column headers to sort
Ligand Sp. Action Value Parameter Concentration range (M) Holding voltage (mV) Reference
paxilline Small molecule or natural product Mm - 8.7 pKi - 0.0 37
pKi 8.7 (Ki 1.9x10-9 M) [37]
Holding voltage: 0.0 mV
toxin BmP09 Peptide Rn - 7.6 pEC50 - 0.0 58
pEC50 7.6 [58]
Holding voltage: 0.0 mV
BmTx2 Peptide Hs - 9.5 pIC50 - - 5,33
pIC50 9.5 (IC50 3x10-10 M) [5,33]
BmTx1 Peptide Hs - 9.2 pIC50 - - 33
pIC50 9.2 (IC50 6.5x10-10 M) [33]
slotoxin Peptide Hs - 8.8 pIC50 - - 14
pIC50 8.8 (IC50 1.5x10-9 M) blocks channels with β1 auxiliary subunit [14]
Penitrem A Small molecule or natural product Hs - 8.2 pIC50 - - 3
pIC50 8.2 (IC50 6.4x10-9 M) [3]
kaliotoxin Peptide Hs - 7.7 pIC50 - - 9
pIC50 7.7 (IC50 2x10-8 M) [9]
BmP09 Peptide Hs - 7.6 pIC50 - - 58
pIC50 7.6 (IC50 2.7x10-8 M) [58]
natrin Small molecule or natural product Hs - 7.5 pIC50 - - 47
pIC50 7.5 (IC50 3.4x10-8 M) [47]
ChTX-Lq2 Peptide Hs - 7.4 pIC50 - - 24
pIC50 7.4 (IC50 4.3x10-8 M) [24]
butantoxin Peptide Hs - 7.3 pIC50 - - 30
pIC50 7.3 (IC50 5x10-8 M) [30]
Lqh Tx 15-1 Peptide Hs - 7.3 pIC50 - - 25
pIC50 7.3 (IC50 5x10-8 M) [25]
martentoxin Peptide Hs - 7.1 pIC50 - - 39
pIC50 7.1 (IC50 7.8x10-8 M) [39]
verruculogen Small molecule or natural product Ligand has a PDB structure Hs - ~7.0 pIC50 - - 27
pIC50 ~7.0 (IC50 ~1x10-7 M) [27]
charybdotoxin Peptide Click here for species-specific activity table Hs - 6.6 pIC50 - - 13
pIC50 6.6 (IC50 2.5x10-7 M) [13]
iberiotoxin Peptide Immunopharmacology Ligand Hs - 6.6 pIC50 - - 12
pIC50 6.6 (IC50 2.5x10-7 M) [12]
clotrimazole Small molecule or natural product Approved drug Click here for species-specific activity table Ligand has a PDB structure Hs - 5.5 pIC50 - - 53
pIC50 5.5 (IC50 3x10-6 M) [53]
tetrandrine Small molecule or natural product Approved drug Click here for species-specific activity table Hs - 5.0 pIC50 - - 46
pIC50 5.0 (IC50 1x10-5 M) [46]
tetraethylammonium Small molecule or natural product Click here for species-specific activity table Ligand has a PDB structure Hs - - - - -
View species-specific channel blocker tables
Channel Blocker Comments
Venom-derived conopeptide Vt3.1 acts as a potassiun channel blocker that preferentially blocks channels with β4 auxiliary subunits (IC50 8.5 μM) [22].
Allosteric Modulators
Key to terms and symbols View all chemical structures Click column headers to sort
Ligand Sp. Action Value Parameter Reference
rimtuzalcap Small molecule or natural product Click here for species-specific activity table Ligand has a PDB structure Hs Activation - - 2
[2]
Tissue Distribution Click here for help
Brain:-
basal nuclei (claustrum)
Expression level:  High
Species:  Rat
Technique:  in situ hybridisation
References:  32,51
Brain:-
neocortex (layer V/VI), pyriform cortex, septum (bed nucleus of the stria terminalis, lateral septum), thalamus (rhomboid nucleus)
Expression level:  Medium
Species:  Rat
Technique:  in situ hybridisation
References:  32,51
Phenotypes, Alleles and Disease Models Click here for help Mouse data from MGI

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Allele Composition & genetic background Accession Phenotype Id Phenotype Reference
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
129-Kcnma1
MGI:99923  MP:0004746 abnormal cochlear IHC afferent innervation pattern PMID: 16763026 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0004433 abnormal cochlear inner hair cell physiology PMID: 17135251 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
129-Kcnma1
MGI:99923  MP:0004433 abnormal cochlear inner hair cell physiology PMID: 16763026 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
129-Kcnma1
MGI:99923  MP:0006324 abnormal cochlear nerve fiber response PMID: 16763026 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0001663 abnormal digestive system physiology PMID: 16571783 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
129-Kcnma1
MGI:99923  MP:0004736 abnormal distortion product otoacoustic emission PMID: 16763026 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0002807 abnormal eye blink conditioning behavior PMID: 15194823 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0003868 abnormal feces composition PMID: 16571783 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0001406 abnormal gait PMID: 15194823 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0001406 abnormal gait PMID: 15184377 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
129-Kcnma1
MGI:99923  MP:0006335 abnormal hearing electrophysiology PMID: 16763026 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0002066 abnormal motor capabilities/coordination/movement PMID: 15194823 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0005620 abnormal muscle contractility PMID: 19220851 
Kcnma1tm1Ruth|Kcnma1tm2.1Ruth|Tg(Myh11-cre/ERT2)1Soff Kcnma1tm1Ruth/Kcnma1tm2.1Ruth,Tg(Myh11-cre/ERT2)1Soff/0
involves: 129/Sv * C57BL/6 * FVB/N
MGI:3819268  MGI:99923  MP:0005620 abnormal muscle contractility PMID: 19220851 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0001731 abnormal postnatal growth PMID: 15194823 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0010386 abnormal urinary bladder physiology PMID: 19220851 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0010386 abnormal urinary bladder physiology PMID: 15184377 
Kcnma1tm1Ruth|Kcnma1tm2.1Ruth|Tg(Myh11-cre/ERT2)1Soff Kcnma1tm1Ruth/Kcnma1tm2.1Ruth,Tg(Myh11-cre/ERT2)1Soff/0
involves: 129/Sv * C57BL/6 * FVB/N
MGI:3819268  MGI:99923  MP:0010386 abnormal urinary bladder physiology PMID: 19220851 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0001761 abnormal urination pattern PMID: 19220851 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0001761 abnormal urination pattern PMID: 15184377 
Kcnma1tm1Ruth|Kcnma1tm2.1Ruth|Tg(Myh11-cre/ERT2)1Soff Kcnma1tm1Ruth/Kcnma1tm2.1Ruth,Tg(Myh11-cre/ERT2)1Soff/0
involves: 129/Sv * C57BL/6 * FVB/N
MGI:3819268  MGI:99923  MP:0001761 abnormal urination pattern PMID: 19220851 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129X1/SvJ
MGI:99923  MP:0004737 absent distortion product otoacoustic emissions PMID: 15328414 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0001393 ataxia PMID: 15194823 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0001393 ataxia PMID: 15184377 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129X1/SvJ
MGI:99923  MP:0004404 cochlear outer hair cell degeneration PMID: 15328414  17074442 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0001262 decreased body weight PMID: 15184377 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0001935 decreased litter size PMID: 15184377 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129X1/SvJ
MGI:99923  MP:0004628 Deiters cell degeneration PMID: 15328414 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0002578 impaired ability to fire action potentials PMID: 15194823 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0001405 impaired coordination PMID: 15194823 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0001405 impaired coordination PMID: 15184377 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0001522 impaired swimming PMID: 15194823 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129X1/SvJ
MGI:99923  MP:0006042 increased apoptosis PMID: 15328414 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0001994 increased blinking frequency PMID: 15194823 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0004037 increased muscle relaxation PMID: 19220851 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0004925 increased resistance to noise-induced hearing loss PMID: 17135251 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129X1/SvJ
MGI:99923  MP:0004597 increased susceptibility to noise-induced hearing loss PMID: 17074442 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0002916 increased synaptic depression PMID: 15194823 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0002842 increased systemic arterial blood pressure PMID: 15194823 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0002083 premature death PMID: 15184377 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129X1/SvJ
MGI:99923  MP:0004740 sensorineural hearing loss PMID: 15328414 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0001407 short stride length PMID: 15194823 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0001407 short stride length PMID: 15184377 
Kcnma1tm1Ruth Kcnma1tm1Ruth/Kcnma1tm1Ruth
involves: 129/Sv * C57BL/6
MGI:99923  MP:0000745 tremors PMID: 15194823 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0001396 unidirectional circling PMID: 15184377 
Kcnma1tm1Rwa Kcnma1tm1Rwa/Kcnma1tm1Rwa
FVB.129-Kcnma1
MGI:99923  MP:0003280 urinary incontinence PMID: 15184377 
Clinically-Relevant Mutations and Pathophysiology Click here for help
Disease:  Generalized epilepsy and paroxysmal dyskinesia
OMIM: 609446
Orphanet: ORPHA79137
General Comments
Channel openers may have applications in stroke, epilepsy, bladder over-reactivity, asthma, hypertension, gastric hypermotility and psychoses [8,16,20].

Crystal Structures have been solved for the Intracellular Gating Rings [54,59-60].

A gene therapy plasmid vector that expresses human KCa1.1 (URO-902) is in clinical development as a novel therapeutic approach for the treament of overactive bladder syndrome associated with detrusor overactivity [11,35]. URO-902 is delivered either by a single intravesical instillation or by direct injections into bladder detrusor muscle, thus limting effects to bladder tissue.

References

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1. Agarwal S, Kim ED, Lee S, Simon A, Accardi A, Nimigean CM. (2025) Ball-and-chain inactivation of a human large conductance calcium-activated potassium channel. Nat Commun, 16 (1): 1769. [PMID:39971906]

2. Amrutkar DVm Foster K, Jacobsen TA, Jefson MR, Keaney GF, Larsen JS, Nielsen KS. (2018) Potassium channel modulators. Patent number: US9975886B1. Assignee: Cadent Therapeutics Inc. Priority date: 23/01/2018. Publication date: 22/04/2018.

3. Asano S, Bratz IN, Berwick ZC, Fancher IS, Tune JD, Dick GM. (2012) Penitrem A as a tool for understanding the role of large conductance Ca(2+)/voltage-sensitive K(+) channels in vascular function. J Pharmacol Exp Ther, 342 (2): 453-60. [PMID:22580348]

4. Bentzen BH, Nardi A, Calloe K, Madsen LS, Olesen SP, Grunnet M. (2007) The small molecule NS11021 is a potent and specific activator of Ca2+-activated big-conductance K+ channels. Mol Pharmacol, 72 (4): 1033-44. [PMID:17636045]

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