| ApplicationNotes | Immunohistochemistry:1:100-1:250.Seeimmunohistochmistryprocedurebelow. 
 Optimalworkingdilutionsmustbedeterminedbytheenduser.
 
 IMMUNOHISTOCHEMISTRYPROCEDURE(PAPTECHNIQUE)FORMAB305,MONOCLONALANTIBODYTOCHOLINEACETYLTRANSFERASE
 
 I)Perfusion&SectioningProcedure
 
 1.Perfusethroughtheheartwithafixativesolutioncontaining4%paraformaldehydein0.12Mphosphatebuffer(pH7.3)forlightmicroscopy(LM),andadditionally,0.1%gluteraldehydeand.002%CaCl2forelectronmicroscopy(EM).
 
 2.Removebrainandpostfix2-18hoursat4°Cin4%paraformaldehydein0.12Mphosphatebuffer.
 
 3.Afterbrainisblockedforsectioning,washinseveralchangesofbufferfor2-3hours.
 
 4.SpecimensforEMaresectionedonaVibratome(50μm)andrinsedinbuffer,thoseforLMshouldbecryoprotectedin30%sucroseinbuffer.
 
 5.Afterfreezingwithdryice,30-40μmthicksectionsofLMspecimensarecutonacryostat.
 
 6.Sectionsarerinsed,andthenstoredinphosphatebuffercontaining0.1%sodiumazide.
 
 II)StainingProcedure
 
 Tissueisprocessedasfreely-floatingsectionsincontinuouslyagitatedsolutions.Allincubationsareperformedatroomtemperatureunlessotherwisestated.
 
 1.a.ForlocalizingChAT-positivesomataanddendrites:
 
 Sectionsarewashedin0.1MTris-bufferedsaline(TBS;containing1.4%NaCl,pH7.3)only.Nodetergentorenzymepretreatmentisused.
 
 b.ForlocalizingChAT-positiveterminal-likestructures:
 
 IncubatesectionsinTBS(pH8.1)for5minutesat37°C.TransfersectionstoTBS(pH8.1)containingpronase(1.2μg/mL)for11/2-2minutesat37°C,followedbyseveralicecoldbufferwashesforatotalof5minutes.Theconcentrationofpronaseandincubationtimeofthedigestionshouldbeevaluatedforeachregionexamined.
 
 c.ForlocalizingChATimmunoreactivityandsubsequentlycounterstainingthesections:
 
 IncubationinTBScontaining0.1%-0.8%TritonX-100for15minutesmayincreasethetissuepenetrationoftheImmunoReagents,butitalsoraisesthebackgroundstaining.
 
 2.Incubatesectionsinnormalgoatserum(3-5%)foronehour.Theworkingsolutionsofallantiserashouldalsocontainsimilarlydilutednormalgoatserum.
 
 3.Incubateinanti-ChATmonoclonalantibodysolution(Suggestedworkingdilution1:250,finalworkingdilutionmustbedeterminedbyenduser)for2hoursatroomtemperatureandthenforanadditional6-18hoursat4°C.
 
 4.Incubatewithsecondantibody(i.e.Goatanti-MouseIgG,Cat.No.:AP124,dilution1:50-100)for1-2hours.
 
 5.IncubatewithdilutedPAPcomplex(i.e.MousePAP,CatNo.:PAP14,conc.25-50μg/mL)foronehour.
 
 6.Afterrinsinginbuffer,thesecondantibodyandPAPstepsarerepeatedfor40minutesto1houreachinordertoamplifystainingintensity,particularlyofsmallChAT-containingstructures.
 
 7.Reactfor15minuteswith0.06%3,3"-diaminobenzidine×4HCl(DAB;dilutedinphosphatebufferedsaline,pH7.3)and0.006%H2O2.
 
 8.SpecimensforroutineLMarepostfixedfor1minutesin0.005%OsO4(osmiumtetraoxide),andthenmounted,dehydratedandcoverslipped.SelectedregionsblockedforEMarepostfixedin2%OsO4for1hour,enblocstainedwithuranylacetate,andflat-embeddedinEpon-Aralditeresin.
 |