SenicapocisapotentandselectiveGardoschannelblockerwithIC₅₀valueof11nM,andblocksCa²⁺-inducedrubidiumfluxfromhumanRBCswithanIC₅₀valueof11nMandinhibitsRBCdehydrationwithIC₅₀of30nM.

IC50:11nM(Gardoschannel)

ICA-17043isshowntoblocktheGardoschannelofmouse(C57Black)RBCswithanIC₅₀of50±6nM.ICA-17043blocksthisincreaseincellularhemoglobinconcentrationinhumanRBCsinaconcentration-dependentfashion^[1].

ICA-17043 (10mg/kg,p.o.)admiNISTrationproducesasignificantdecreaseinGardoschannelactivitymeasuredatday11and21andisassociatedwithacorrespondingincreaseinredcellK⁺contentwithoutchangesinNa⁺content.ICA-17043(10mg/kg,twiceaday)inducesasignificantincreaseinHctafter11daysofdosingintheSADmouse^[1].Senicapoc(30mg/kg,p.o.)reducesairwayhyperresponsiveness,eosinophilnumbersinbronchoalveolarlavagetaken48hourspost-allergenchallenge,andvascularremodellinginthesheep^[2].

• [1].StockerJW,etal.ICA-17043,anovelGardoschannelblocker,preventssickledredbloodcelldehydrationinvitroandinvivoinSADmice.Blood.2003Mar15;101(6):2412-8.

  [2].VanDerVeldenJ,etal.K(Ca)3.1channel-blockadeattenuatesairwaypathophysiologyinasheepmodelofchronicasthma.PLoSOne.2013Jun24;8(6):e66886.

  [3].StaalRG,etal.InhibitionofthepotassiumchannelKCa3.1bysenicapocreversestactileallodyniainratswithperipheralnerveinjury.EurJPharmacol.2017Jan15;795:1-7.

SenicapocisdissolvedinDMSOor100%ethanol.

Thewholebloodisinitiallydiluted1:1withModifiedFluxBuffer(MFB),consistingof140mMNaCl,5mMKCl,10mMTris(tris(hydroxymethyl)aminomethane),0.1mMEGTA(ethyleneglycoltetraaceticacid)(pH=7.4).Thebloodiscentrifugedat1000rpm,andthepelletcomprisedprimarilyofRBCsiswashed3timeswithMFB.Thecellsarethenloadedwith ⁸⁶Rb⁺ byincubatingthewashedcellswith⁸⁶Rb⁺ atafinalconcentrationof0.185MBq/mL(5μCi/mL)inMFBforatleast3hoursat37°C.AfterloADIngwith⁸⁶Rb⁺,theRBCsarewashed3timeswithchilledMFB.Thecellsarethenincubatedfor10minuteswithtestcompound(senicapoc)atconcentrationsthatrangedfrom1nMto10000nM.Effluxof ⁸⁶Rb⁺ isinitiatedbyraisingintracellularcalciumlevelsintheRBCswiththeadditionofCaCl₂ andA23187(acalciumionophore)tofinalconcentrationsof2mMand5μM,respectively.After10minutesofincubationatroomtemperature,theRBCsarepelletedinamicrocentrifuge,andthesupernatantisremovedandcountedinaWallacMicroBetaliquidscintillationcounter. MCEhasnotindependentlyconfirmedtheaccuracyofthesemethods.Theyareforreferenceonly.

Senicapocisdissolvedinacremophore/PEG-400/water(10:10:80)mixture.

TransgenicHbbsingle/single SAD1(SAD)femaleandmalemice between3and6monthsofage,weighing25to30g,areusedforthisstudy.TheSADmicearedividedinto2groups,andeithervehicle(n=6)orsenicapoc(10mg/kg)(n=6)isadministeredorallybygavagetwicedaily.C57B6/2Jmiceareusedascontrols(wild-typemice).Hematologicparametersareevaluatedatbaselineandafter11and21daysoftherapy.Bloodsamplingandvehicleadministrationhavepreviouslybeenshownnottoaffectthebloodparametersmeasuredinthisstudy.MCEhasnotindependentlyconfirmedtheaccuracyofthesemethods.Theyareforreferenceonly.

• [1].StockerJW,etal.ICA-17043,anovelGardoschannelblocker,preventssickledredbloodcelldehydrationinvitroandinvivoinSADmice.Blood.2003Mar15;101(6):2412-8.

  [2].VanDerVeldenJ,etal.K(Ca)3.1channel-blockadeattenuatesairwaypathophysiologyinasheepmodelofchronicasthma.PLoSOne.2013Jun24;8(6):e66886.

  [3].StaalRG,etal.InhibitionofthepotassiumchannelKCa3.1bysenicapocreversestactileallodyniainratswithperipheralnerveinjury.EurJPharmacol.2017Jan15;795:1-7.

323.34

C₂₀H₁₅F₂NO

289656-45-7

RoomtemperatureincontinentalUS;mayvaryelsewhere

10mMinDMSO

Senicapocisformulatedwith20%2-Hydroxypropyl-β-cyclodextrinasasUSPension^[3].

*"<1 mg/ml"="" means="" slightly="" soluble="" or="" insoluble.="" "≥"="" means="" soluble,="" but="" saturation="">

• [1].StockerJW,etal.ICA-17043,anovelGardoschannelblocker,preventssickledredbloodcelldehydrationinvitroandinvivoinSADmice.Blood.2003Mar15;101(6):2412-8.

  [2].VanDerVeldenJ,etal.K(Ca)3.1channel-blockadeattenuatesairwaypathophysiologyinasheepmodelofchronicasthma.PLoSOne.2013Jun24;8(6):e66886.

  [3].StaalRG,etal.InhibitionofthepotassiumchannelKCa3.1bysenicapocreversestactileallodyniainratswithperipheralnerveinjury.EurJPharmacol.2017Jan15;795:1-7.