impact of prophylactic intranasal oxytocin …
TRANSCRIPT
![Page 1: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/1.jpg)
Eastern Washington UniversityEWU Digital Commons
EWU Masters Thesis Collection Student Research and Creative Works
Spring 2017
IMPACT OF PROPHYLACTIC INTRANASALOXYTOCIN ADMINISTRATION ONSYMPTOMS OF POST-TRAUMATIC STRESSMorgan A. ThomasEastern Washington University
Follow this and additional works at: http://dc.ewu.edu/theses
Part of the Biology Commons
This Thesis is brought to you for free and open access by the Student Research and Creative Works at EWU Digital Commons. It has been accepted forinclusion in EWU Masters Thesis Collection by an authorized administrator of EWU Digital Commons. For more information, please [email protected].
Recommended CitationThomas, Morgan A., "IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN ADMINISTRATION ON SYMPTOMS OFPOST-TRAUMATIC STRESS" (2017). EWU Masters Thesis Collection. 437.http://dc.ewu.edu/theses/437
![Page 2: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/2.jpg)
IMPACTOFPROPHYLACTICINTRANASALOXYTOCINADMINISTRATIONON
SYMPTOMSOFPOST-TRAUMATICSTRESS
__________________________________________________________________________________________________
AThesis
PresentedTo
EasternWashingtonUniversity
Cheney,Washington
__________________________________________________________________________________________________
InPartialFulfillmentoftheRequirements
fortheDegree
MasterofScienceinBiology
__________________________________________________________________________________________________
By
MorganA.Thomas
Spring2017
![Page 3: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/3.jpg)
ii
THESISOFMORGANTHOMASAPPROVEDBY
________________________________________________________________DATE_____________DAVIDDABERKOW,GRADUATECOMMITTEECHAIR_________________________________________________________________DATE_____________JAVIEROCHOA-REPARAZ,GRADUATECOMMITTEEMEMBER_________________________________________________________________DATE_____________ANDREWOSTER,GRADUATECOMMITTEEMEMBER
![Page 4: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/4.jpg)
iii
Abstract
Post-traumaticstressdisorder(PTSD)isamentalhealthconditionthataffects
peopleafterinstancesofsevereemotionaltrauma.Researchsuggeststhatoxytocin
treatmentdecreasesPTSDsymptoms.Thisstudyservedtoevaluatetheefficacyof
intranasaloxytocinpre-treatmentonsymptomsrelatedtoPTSD.Thehypotheses
arethatoxytocinwilldecreasefearandanxiety,andincreasereward-seeking
behaviors.SpragueDawleyratswereassignedtothreegroups(Control,Stress,
Oxytocin,andOxytocin+Stress;n=6pergroup)toconductthisexperiment.Priorto
footshocktreatment,ratsweretrainedtoexpectafoodreward(Kellogg’sFroot
Loops)inanopenfieldenclosure.Subsequently,theOxytocinandthe
Oxytocin+Stressgroupswerepre-treatedwithintranasaloxytocinandthenthe
StressandOxytocin+Stressgroupswereexposedtoaninescapablefootshock(a
modelPTSDinducingstressor).Afteroxytocinandshocktreatments,rats
underwentvariousbehavioraltests:re-exposuretotheshockchambertoassess
fear,elevatedO-mazetoassessanxiety,andfoodrewardtrialsintheopenfield
enclosuretoassessreward-seekingbehavior.Theoxytocintreatmentdecreased
fearrelatedsymptomsuponre-exposuretothefearconditioningchamber;both
colonicmotilityandfreezingtimewerelowerintheOxytocin+Stressgroup
comparedtotheStressgroup.Thefootshockmodelfailedtoproducesignificant
behavioralchangesrelatedtoanxietyandreward-seekingbehaviorbetweenthe
ControlandStressgroups.
![Page 5: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/5.jpg)
BackgroundandSignificance
PTSD
Post-traumaticstressdisorder(PTSD)isamentalhealthconditionthataffects
peopleafterinstancesofsevereemotionalorphysicaltrauma.Diagnosticcriteria
arecomplexandsymptomsvarybetweenindividuals,butincludeemotional
distress,physicalreactivity,avoidanceoftraumarelatedreminders,decreased
interestinactivities,anddifficultyexperiencingpositiveaffect(American
PsychiatricAssociation,2013).Itisestimatedthatbetween8.3%and9.4%percent
oftheUnitedStatespopulationdevelopsdiagnosablePTSDintheirlifetime
(Kilpatricketal.,2013).
RodentModelofPTSD
Whilepreviousresearchershaveusedcorticosteroneadministrationtoinduce
symptomsofPTSDinrodents(Levyetal.,2001),morerecentlyafear-conditioning
paradigmusingchronicelectricfootshock(describedintheMethodssection)has
beendevelopedtoinducePTSD-likesymptomsinaratmodel(Sahraeietal.,2012;
Yuetal.,2012;Gaoetal.,2014).Thisparadigmproducesbehavioralchangesinrats
suchasfearandanxiety,whichareknowntobeassociatedwithPTSD.
Fearinratsiscommonlyassessedbyincreasedfreezingbehavior(Fanselow,
1994;Sahraeietal.,2012;Yuetal.,2012;Gaoetal.,2014).Freezingisdefinedas
motionlessperiodsuponre-exposuretothepreviouslytraumatizingsourceof
stimuli,thefootshockchamber(Yuetal.,2012;Gaoetal.,2014),andisahallmark
ofstress-inducedbehavioralchangesinrodents.Anotherassessmentoffearin
rodentsisincreaseddefecationwhenre-exposedtofearrelatedstimuli(Lesteretal.,
![Page 6: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/6.jpg)
2
1968;Gaoetal.,2011).Increaseddefecation,oftenreferredtoas“colonicmotility”,
isameasurehighlysensitivetopsychologicalstress(Stametal.,1995).Colonic
motilityisthoughttoberegulatedbythereleaseofcorticotropin-releasinghormone
causedbystressfulevents(Verleye&Gillardin,2004).
Anxietyiscommonlymanifestedandmeasuredinrodentsasdecreased
locomotion(Fernandesetal.,1999;Prut&Belzung,2002)andincreasedtimein
enclosedspaces(Pellowetal.,1985;Shepherdetal.,1994;Ennaceuretal.,2006).
Manydifferentmethodshavebeenusedtoassessanxietyinrodentsandincludethe
open-fieldtest,elevatedplus-maze,andelevatedO-maze(reviewedinSestakovaet
al.,2013).Theopen-fieldtestisthesimplestandlongestusedanxietytestforrats,
datingbackto1930’s(HallandBallachey,1932).Whilespecificrequirementsofthe
open-fieldarenotstandardized,ingeneralitconsistsofanopenareainwhich
ambulationcanbeobserved(WalshandCummings,1976).Thetestmeasures
locomotionandpropensitytoexplore;loweramountsoflocomotionand
explorationcorrelatetohigherlevelsofanxiety(Peralsetal.,2017;Prutand
Belzung2003).Theelevatedplus-mazeisafour-armedmazethatisraisedoffthe
groundbylegs.Eacharmisconnectedatacenterplatform.Twoarmsoftheplus-
mazehavehighwallsandtheothertwoarmsdonothavewalls.Thetimespentin
thewalledareasisassociatedwithanxiousbehavior(Pellowetal.,1984;Rodgers
andDalvi,1997)astheratisthoughttobeavoidingthenoveltyoftheopenarea
(Dawson&Tricklebank,1995).TheelevatedO-maze(orelevatedzero-maze)was
developedasanimprovementtotheelevatedplus-maze.Theconceptsoftheplus-
maze,suchasheightoffthegroundandtheopenversusclosedareas,remainthe
![Page 7: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/7.jpg)
3
samebuttheO-mazeformsacontinuouscircle(orzero)withalternatingquadrants
ofopen(nowalls)andclosed(walledoff)areas.Thisconfigurationallowsforeasier
explorationbetweenmazesectionssincetherearenocornersandtheratsdonot
havetoturnaroundwhilecontinuingtomoveaboutthemaze(Shepherdetal.,
1994).IthasbeensuggestedthattheelevatedO-mazeproducesmoreconsistent
resultsovertime(Tucker&McCabe,2017);however,theresultsoftheelevatedO-
mazearediminishedbydailyre-exposure(Cooketal.,2001).
Anhedonia(thedecreaseinthecapacitytofeelpleasure)hasrelatively
recentlybeenincorporatedintothediagnosticcriteriaofPTSD(Steinetal.,2014).It
isthoughtthatPTSDmaybeassociatedwithreward-seekingimpairments.While
theresponseisvaried,thereseemstobeanoveralldecreaseinrewardanticipation,
approach(orwanting),andhedonicresponsestoreward(Nawijnetal.,2015).This
symptomofPTSD,observedinhumans,hasnotyetbeeninvestigatedintherodent
model.Rewardseekinginrodentsismostcommonlyassessedbytheuseofan
operantbox(Dingessetal.,2017;Piantadosietal.,2017).Sinceoperantboxesare
currentlynotavailableinourlab,oneofthegoalsofthisstudywastoinvestigate
theimpactofstressonthereward-seekingbehaviorinanopenfieldcircular
enclosure(describedintheMethodssection).Furthermore,arecentstudy
conductedbyNawijnetal.(2016)suggeststhatoxytocintreatmentinhumanswith
PTSDappearstoimpactthebrainregionsinvolvedinrewardprocessing.Therefore,
anothergoalofthisstudywastoinvestigatetheimpactofoxytocinonPTSD-related
behaviors(i.e.,fear,anxiety,andreward-seeking).
Oxytocin
![Page 8: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/8.jpg)
4
Oxytocinisaneurohormoneproducedbyneuronsoftheparaventricularand
supraopticnucleiinthehypothalamus.Itisassociatedwithmanyfunctionsofthe
bodyincludinghumanemotionandmotivation(Love,2014).Administeredafter
traumatization,oxytocinhasbeenshowntoreducesymptomsassociatedwithPTSD
(i.e.,fearandanxiety)inbothrodent(Missigetal.,2010;Ayersetal.,2011;Zoicaset
al.,2014;Janezicetal.,2016;Sacketal.,2017)andhumanclinicaltrials
(Bakermans-Kranenburg&VanIJzendoorn,2009;Achesonetal.,2013;Frijilinget
al.,2014).
Oxytocinisaneuropeptidethatdirectlyinteractswithoxytocinreceptorsin
specificpartsofthecentralnervoussystem,assuchitisconsidereda
neuromodulatorinbrainregionsassociatedwithfear,aggressionandsocial
behaviors(Febo&Ferris,2014;Heinrichs&Domes,2008).Oxytocinreceptorsare
expressedintheamygdala,whichisanareaofthebrainintimatelyinvolvedin
processingofemotionandcognition(reviewedinPhelps,2006).Furthermore,
oxytocinreceptorsarealsofoundinrewardprocessingareasofthebrain(Feboand
Ferris,2014)includingtheventraltegmentalareaandthenucleusaccumbens(Wise
andBozarth,1987;Nicola,2016).Hypothalamicoxytocinneuronshavedirect
axonalconnectionstotheamygdala,ventraltegmentalarea,andnucleusaccumbens
andarethoughttodirectlymodulatetheactivityofthesebrainregions(Bethlehem
etal.,2012).
Inadditiontoitsdirecteffectsonbrainregionsassociatedwiththe
processingofemotionsandmotivation,oxytocinalsointeractswiththe
hypothalamic-pituitary-adrenal(HPA)axis.Thisendocrinefeedbacksystemis
![Page 9: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/9.jpg)
5
implicatedinstressreactionsaswellasregulatingmanybodyprocesses(Bhatnagar
etal.,2006;Stranahanetal.,2008;Halletal.,2012;Daskalakisetal.,2013).TheHPA
axiscanbemodifiedpermanentlybyearlychildhoodtrauma,renderingithyper
reactive(vanBodegometal.,2017).Oxytocinhasbeenshowntoinhibitstress
responsesassociatedwiththeHPAaxissuchascorticosteronerelease(Windleetal.,
1997;Heinrichsetal.,2003;DeKloetetal.,2006).Asanaturalmechanism,oxytocin
offersprotectiontostressassociatedwiththeHPAaxisinpostpartum,
breastfeedingmothers(Coxetal.,2014).Oxytocinlevelsriseperipherallyfollowing
stressfulincidentsandhigheroxytocinlevelscorrespondtofasterrecoveryfrom
stressrelatedsymptoms(Engertetal.,2016).Therefore,oxytocintreatmentcould
potentiallyprovideneuroprotectionduringstressfulevents.
Prophylaxis
Variouspharmaceuticalandpsychosocialinterventionshavebeenstudiedas
potentialpreventativetreatmentsforPTSD(reviewedinBakeretal.,2009;
Daskalakisetal.,2013).Mostpreventativemeasuresthathavebeenexploredfall
intothecategoryof“earlyintervention”inwhichtreatmentisgivenafterthe
traumaticevent,butpriortodevelopmentofPTSDrelatedsymptoms(reviewedin
Biruretal.,2017).Multipledrugshavebeenstudiedaspotentialpreventative
treatmentsforPTSD(Vaivaetal.,2003;Bakeretal.,2009;Daskalakisetal.,2013,
Morenaetal.,2017).However,theefficacyofoxytocinasaprophylactic,or
preventative,treatmenthasbeenminimallyexploredinhumans(Frijlingetal.,
2014;vanZuidenetal.,2017)andthereisadearthofresearchwithrodents
![Page 10: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/10.jpg)
6
(Renickeretal.,2015).Oxytocinmayofferthesameneuroprotectivebenefitsof
othertreatments(Vaivaetal.,2003;Bakeretal.,2009;Daskalakisetal.,2013,
Morenaetal.,2017)withouttherisksassociatedwithlong-termtreatment,
includingantidiuresisandhyponatremia(Bakeretal.,2009).
IntranasalAdministration
Intranasaladministrationofoxytocinisaneffectivetherapeuticdelivery
methodinhumans(Fischer-Shoftyetal.,2010;Guastellaetal.,2010;Achesonetal.,
2013;Nawijnetal.,2016).Whilethemechanismsarenotclearlyunderstood,
intranasaloxytocinadministrationproduces“clearandspecificchangesinneural
activation”(Veening&Olivier2013)andhasbeenshowntoincreaselevelsof
oxytocinincerebralspinalfluid(Stevensetal.2013,Streipensetal.,2013).
Intranasaloxytocinadministrationhasalsobeenshowntoimpactspecificbrain
regionsconsidered‘social’regions(Bethlehemetal.,2012).Oxytocinisaverysmall
peptideofnineaminoacids(anonapeptide)andisbelievedtoatleastpartiallypass
throughthebloodbrainbarrier(Ermischetal.,1985).Oxytocinadministrated
intranasallyisthoughtbypassthebloodbrainbarrier(Talegaonkar&Mishra2004)
andhasbeenshowntoproducehigherlevelsofoxytocininthebrainthan
peripheraladministration(Neumannetal.,2013).Additionally,peripheraloxytocin
mayhavedifferenteffectsonstressthanoxytocindelivereddirectlyintothecentral
nervoussystemviaintranasaladministration.Onestudyfoundthatincreased
![Page 11: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/11.jpg)
7
plasmaoxytocinlevelscorrelatetoincreasedcortisollevels(Tayloretal.,2006),
althoughcausationwasnotimplied.Researchsuggestingthatintranasal
administrationofoxytocindirectlyandeffectivelyimpactsbrainfunctionwarrants
investigationintoitspotentialtherapeuticeffectsonconditionssuchasPTSD.
Thepurposeofthisstudywastotestthehypothesisthatprophylactic
oxytocintreatmentwithdecreasePTSDrelatedsymptomsinaratmodel,
specificallydecreasingfearandanxietyrelatedbehaviorsandincreasingreward-
seekingbehaviors.
Methods
Twenty-fourmaleSpragueDawleyratswererandomlyassignedtofour
groups(n=6,pergroup):1.Controlgroup(noshockandnooxytocintreatment),2.
Stressgroup(exposedtoshockandnooxytocintreatment),3.Oxytocingroup(no
shockandtreatedwithoxytocin),and4.Oxytocin+Stressgroup(treatedwith
oxytocinandexposedtoshock).Forpracticalpurposestheratsweresplitinto3
cohorts,testingn=2ratsfromeachtreatmentgroupatatime(2-3month
timeframe).
Generalhousing
Ratswerehousedindividuallytomosteffectivelymonitorfoodconsumption
duringbehavioraltasks.Ratswerehousedinapolysulfonefiltertopcage.Cages
containedcorncobbedding,PVCpipe,andwatersuppliedadlibitum.“Harlan2018”
foodwasprovidedadlibitum,exceptduringtheweeksoffooddeprivation
![Page 12: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/12.jpg)
8
(describedbelow).Allratswerehousedinthesameroomkeptatatemperatureof
22+1°C,andahumidityof23-33%witha12hourlight/darkcycle.
RewardTraining
Priortooxytocintreatmentandfearconditioning(footshock),allratswere
pre-trainedtoexpectandretrieveafoodreward(Kellogg’sFrootLoop)inacircular
openfieldenclosure(3-ftx3-ft,1-ftwalls)witharewarddeliverytubeatoneend
(Fig.1).Foroneweek,ratswerehabituatedtotheenclosurebyallowingthemto
roamfreelyforaminimumof5-10minutesaday(Monday-Friday),threeFroot
Loopsweredeliveredintothechamberduringthistimetofamiliarizethemtothe
rewarddeliveryprocedureandassesstheirinterestinthefoodreward.Forthenext
2-3weeksratswerefoodrestricted,placedinastartboxintheopenfieldenclosure
and3FrootLoopsweredeliveredindependentlyintothereward-seekingarea(Fig.
1).Foreachreward-seekingtrial,theratwasplacedinthestartbox,theFrootLoop
wasdeliveredandthestartboxdoorwasopenedmanuallybytheexperimenter.
Thetimefortherattoretrievethereward(withinaminuteofrewarddelivery)was
monitoredandrecordedasanassessmentoftheir“reward-seeking”behavior.
FoodDeprivation
Afterthefirstweekofhabituation,ratswerefoodrestrictedonMonday-
Fridayandfedadlibitumontheweekends.Ratswereweigheddailywhilefood
restrictedandgivenanamountoffoodthatcorrelatedtotheirweightchange.Rats
wholost0-5grams,orgainedweightwerefedonehalfofafoodpellet,thosewho
lost6-10gramswerefed1pellet,ratswholost11-15gramswerefed1.5pelletsand
![Page 13: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/13.jpg)
9
thosewholost15gramsormorewerefed2pellets.Ratswhodropbelow80%of
theirstartingweightduringfoodrestrictionwouldhavebeenfedadlibitum,though
therewerenoinstancesofthisinourstudy.
OxytocinAdministration
Ratswerelightlyanesthetizedwithisofluranetocalmthemsufficientlyto
allowforintranasaladministration.TheOxytocin+StressandtheOxytocingroups
weretreatedwithintranasaloxytocinat0.1µL/kg,30minutespriortofear
conditioning(describedbelow)basedonAyersetal.(2011)procedure.TheControl
andStressgroupswereadministeredanequivalentamountofsaline.Theratswere
thenassessedforfear,anxietyandreward-seekingbehaviors(describedbelow).
FearConditioning
TheStressandOxytocin+Stressgroupswereexposedtoanelectricfoot-shock
paradigm(usedasamodelforaPTSDinducingstressor;Gaoetal,2014).Overa
periodofthreedays,ratsinthesegroupswereexposedtofootshocktwicedaily.
Theywereplacedintothefear-conditioningchambertwicedailyandgiven20
inescapablefootshocks(8mAintensity,3secondduration,10secondintervals
betweenshocks;similartoGaoetal.,2014).
BehavioralAssessments
Afteroxytocinandshocktreatments,allratswerereintroducedtotheshock
chambertoassessbehaviorsrelatedtofear(i.e.,timemotionlessanddefecation),
runonanelevatedO-maze(Fig.2)toassessbehaviorsrelatedtoincreasedanxiety
![Page 14: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/14.jpg)
10
(i.e.,decreaseintimespentintheopensegmentsofthemaze),andgiventhree
rewarddeliverytrialsintheopenfieldenclosuretoassessreward-seekingbehavior
(i.e.,timetoretrievereward).
Ratswereplacedintheshockingchamberforfiveminutes,butnotshocked,
toobservefearrelatedbehaviors.Fearisoftenexpressedandmeasuredbyan
increaseinfreezingtime(definedastheabsenceofallmovementsexceptforthose
relatedtorespiration;Gaoetal.2014)andbyanincreaseinfecalproduction(Gaoet
al.,2011)whenreintroducedintothefearconditioning(shocking)chamber.
Therefore,theratswereputbackintotheshockingchamberfor5minutesandwere
observedforfreezingtimeandtheamountoffecalproduction.
Toassessanxiety,theratswereplacedinanelevatedO-mazeforfive
minutes,measuringtheamountoftimespentintheopensegmentswhichis
inverselycorrelatedtoanxietyleveloftheanimalasproposedbyShepherdetal.
(1994).TheelevatedO-maze(Fig.2)consistedofanannularplatformelevated65
cmabovethefloor(105cmindiameter,10cminwidth),theplatformofthe
elevatedO-mazewasdividedinto4segments:2opposingopensegmentswithno
walls,and2opposingclosedsegmentswithwallsextending27cmabovethe
platformsurface.TheO-mazewaslocatedinanotherwiseemptyroomandthe
researchersteppedoutofroomandclosedthedooronceratwasplacedintheopen
segmentoftheO-mazeastonotdistractfromtheratsnormalexploratorybehavior.
Behaviorwasrecordedonvideoforlateranalysis.
![Page 15: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/15.jpg)
11
Toassessreward-seekingbehavior,theratswerethenplacedintheopen
fieldenclosure(Fig.1)for3consecutive1-minutetrials,basedonthereward
trainingprocedure.Atthebeginningofeachtrial,theratwasenclosedinastartbox.
ThestartboxdoorwasopenedandaFrootLoop(foodreward)deliveredthrough
therewarddeliverytube.ThetimetoretrievetheFrootLoopwasmeasured.
Behaviorwasrecordedonvideoforlateranalysis.
Allbehavioraltestsweredonetwice:week1(anxietytested1dayafter
shocktreatment,fearandreward-seekingtested2daysaftershocktreatment)and
againinweek2(anxietytested8daysaftershocktreatment,fearandreward-
seekingtested9daysaftershocktreatment).
Statisticalanalysis
Todeterminesignificantdifferencesinbehavioral(dependent)measures,we
firstcompareddatafromallfourgroupsusingaone-wayANOVA(VassarStats).If
overallsignificance(p≤0.05)wasfound,asubsequentTukey’spost-hocanalysis
wasusedtodeterminesignificantdifferencesbetweenindividualgroups.Standard
two-tailedt-tests(VassarStats)wereusedtoanalyzechangeswithingroups
betweenweekoneandtwo.Wewereparticularlyinterestedinthedifferences
betweentheStressandStress+Oxytocingroupstomostdirectlyaddressthe
objectivesofthisstudy.
Theproceduresdescribedinthisproposalhavebeenreviewedandapprovedbythe
EasternWashingtonUniversityInstitutionalAnimalCareandUseCommittee(effective
June7,2016).
![Page 16: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/16.jpg)
12
Results
Forbehavioralmeasuresassessingfear,wefoundoverallsignificanceinboth
measures(freezinganddefecation),duringbothweek1andweek2(Fig.3,
p<0.0001;Fig.4,p<0.001;Fig.7,p<0.0005;Fig.8,p<0.05).Freezingtimeinseconds
wassignificantlylowerforControl,Oxytocin,andOxytocin+Stressgroupswhen
comparedtotheStressgroup(Fig.3,p<0.01)duringweek1.Inweek2,the
decreasedfreezingtimebetweentheStressgroupandtheOxytocinandControl
groupsremainedsignificant(Fig7,p<0.01)buttheOxytocin+Stressgroupwasno
longersignificantlylowerthantheStressgroup,orsignificantlyhigherthanthe
Controlgroup(Fig7).Whencomparingweek1toweek2,thefreezingtimesforthe
Stressgroupshowsasignificantdecreaseovertime(Fig.11,p<0.05)whilethis
decreasefortheOxytocin+Stressgroupwasnotsignificantacrossthetwoweeks(Fig.
11).
FecalProduction(measuredingramsoffeces)wassignificantlylowerfor
Control,Oxytocin,andOxytocin+StressgroupswhencomparedtotheStressgroup
(Fig.4,p<0.05)inweek1afterfearconditioning.Byweek2theStressgroupwas
stillsignificantlyhigherthantheOxytocinandControlgroups(Fig8,p<0.01)butthe
Oxytocin+StressgroupwasnolongersignificantlylowerthantheStressgroup,or
significantlyhigherthantheControlgroup(Fig8).
Testsforanxietyandrewardseekingbehaviorfailedtoproducesignificant
resultsineitherweek1orweek2(overallone-wayANOVA;Fig.5,p=0.15;Fig.6,
p=0.47;Fig.9,p=0.68;Fig.10,p=0.55).
![Page 17: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/17.jpg)
13
Discussion
ItisclearthatthePTSDparadigmworkedtoinducefearintheratsbasedon
thedifferencesbetweentheControlandStressgroups(Fig.3-4,Fig.7-8).These
resultsalsosupportedourhypothesisthatprophylacticoxytocintreatmentwould
decreasefearrelatedbehaviorsafteraPTSD-likestressor.WhiletheOxytocin+Stress
grouphadincreasedfearrelatedbehaviorscomparedtotheControlgroup,boththe
timespentfreezing(Fig.3)andtheamountoffecalproduction(Fig.4)were
decreasedsignificantlycomparedtotheStressgroup.However,thesignificant
differenceinfearrelatedbehaviorsbetweentheStressandOxytocin+Stressgroups
doesnotcontinueinthesecondweekpoststressor(Fig.7-8).Thislackof
significancecouldbeduetotheattenuationoffearresponsesovertimeintheStress
groupwhichdecreasedfromweekonetoweektwo,asopposedtodiminished
efficacyoftheprophylactictreatmentintheOxytocin+Stressgroup,whichalso
decreasedinfearrelatedmeasuresbutwerenotsignificant(Fig.11).
AstherewasnosignificanceinanxietyrelatedbehaviorsbetweentheControl
andtheStressgroups(Fig.5andFig.9),itappearsourparadigmdidnotworkfor
testingorinvokingthesesymptoms.ItisunclearwhytheelevatedO-mazedidnot
produceresultsasithasshowntobereliableinothersimilartestsofthePTSD-like
model(Gaoetal.,2014;Renickeretal.,2015).Gaoetal.(2014)whodevelopedthe
PTSD-likemodelinratsusedanelevatedplus-mazetotestanxietysotheirresults
cannotbecompareddirectlytoourO-mazeresults,althoughasimilareffectwould
beexpected.Onepossibleexplanationisthetemporalsequenceoftesting,Gaoetal.
![Page 18: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/18.jpg)
14
(2014)performedtheelevatedplus-mazetestafterre-exposuretothefear
conditioningchamberwhileourelevatedO-mazetestsweredonethedaybeforere-
exposure.Renickeretal.(2015)alsotestedtheelevatedO-mazeafterre-exposure
tothefearconditioningchamber,althoughtherewasagapoftime(5days)between
thetests.Previousresearchhassuggestedthatareminderofthestressexperience
caninfluencememoryandbehavior(Zoladzetal.,2010;Burkeetal.,2013).Assuch,
itispossiblethatthere-exposuretothefear-conditioningchamberenhancedthe
anxietyresponseseeninthepreviousstudiesofGaoetal.(2014)andRenickeretal.
(2015).
Therewasalsoalackofsignificanceinreward-seekingbehaviorsbetween
theControlandtheStressgroups(Fig.6andFig.10).Sincereward-seeking
behaviorshavenotbeenanalyzedintherodentmodelofPTSD,itispossiblethat
thesebehaviorsarenotaffectedinrodentsasisfoundinhumancasesofPTSD.
Alternatively,sincethereward-seekingparadigmusedinthisstudywasdeveloped
inourlabasacosteffectivesubstitutetotheclassicaloperantbox,itispossiblethat
thesereward-seekingbehaviorsareimpactedintheratmodelofPTSDbutour
dependentmeasuresdidnotexposetheseeffects.Ifthisexperimentweretobe
repeated,itmightbenefitfromtheuseofoperantboxesashasbeenusedin
previousstudiestoassessreward-seekingbehaviors(Dingessetal.,2017;
Piantadosietal.,2017).
Animportantaspecttoconsideristhetimingof“prophylaxis”.Whileour
studydefinedprophylaxisastreatmentpriortothetraumaticstressor,otherstudies
![Page 19: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/19.jpg)
15
definepreventativetreatmentasinterventionsperformedsoonafterthetraumatic
eventbeforesymptomsofPTSDmanifest,alsocalled“earlyintervention”(Vaivaet
al.,2003;Bakeretal.,2009;Daskalakisetal.,2013;Rothbaumetal.,2014;Frijlinget
al.,2014;Renickeretal.,2015).Earlyinterventionorprophylactictreatmentscould
alsobeaffectingdifferentmechanismsthantraditionaltreatments,suchasmemory
consolidation(Morenaetal.,2017).Futurestudiesshouldevaluatetheprosand
consofeachmethod.Treatmentafterthetraumaticeventwouldbemostpractical
asthevastmajorityoftraumaticeventscannotbepredicted;however,iftreatment
beforeatraumaticstressorofferssignificantprotectionitcouldbebeneficialin
settingssuchascombatwarfare,lawenforcementoperations,andsurgicalsettings.
Whetheroxytocintreatmentisdeliveredsoonafterthetraumaticevent
(Frijlingetal.,2014;Renickeretal.,2015;vanZuidenetal.,2017)orbefore,aswas
doneinthisstudy,researchsuggeststhatintranasaloxytocinadministration
providesneuroprotectionandattenuatesfearrelatedbehaviorsinhumans(Frijling
etal.,2014;vanZuidenetal.,2017)androdents(Renickeretal.,2015).Thedirect
effectsofoxytocinonbrainregionsthatcontainoxytocinreceptorsandprocess
emotion(e.g.,amygdala)arelikelyimplicatedinthebehavioralchangeswe
observedinthemeasuresoffear.Furthermore,PTSDhasbeenshowntoalter
endocrineoutputrelatedtotheHPAaxis(reviewedinDaskalakisetal.,2013).
IntranasaloxytocinadministrationislikelyimpactingtheHPAaxisbuthow
oxytocinalterstheHPAaxisispoorlyunderstood(reviewedinStockhorstand
Antov,2016).
![Page 20: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/20.jpg)
16
Certainfactorsshouldbeconsideredwhendesigningfuturestudies.Genetics
andepigeneticsbothplayaroleinthelikelihoodofdevelopingPTSD(Yehuda&
Bierer2009;Gerritsenetal.,2017)aswellasthepotentialfortreatmentsuccess
(Yehudaetal.,2013).Additionally,sexdifferencesarefoundtobeverypronounced
intheinstancesofPTSD(2:1femaletomaleratio)(Kilpatricketal.,2013)and
oxytocinefficacy(Sacketal.,2017;Smith&Wang2013).Asourstudypopulation
consistedofonlymaleratswewerenotbeabletoaddressthesedifferences.Many
factorsinfluencetheprobabilityofdevelopingPTSD.Inhumans,while
approximately80%ofthepopulationisexposedtotraumaticstressors,onlyasmall
percentage(~11%)ofthemgoontodevelopthedisorder(Kilpatricketal.,2013).
Therefore,arelativelysmallstudysuchasoursmaynotseealargeenoughsample
ofaffectedindividualstogainanaccuraterepresentationoftheeffects.
Theresultsofthisstudysuggestthatfurthertestingiswarrantedtoascertain
whetherornotprophylacticoxytocintreatmentisaneffectiveandpractical
preventionmethodforPTSD.OurfearresultscorroboratethefindingsofvanZuiden
etal.(2017)Friljingetal.(2014)andRenickeretal.(2015);however,theimpactof
prophylacticoxytocintreatmentonanxietyandrewardseekingneedfurther
investigation.
V.LiteratureCited
AchesonD,FeifelD,deWildeS,MckinneyR,LohrJ,RisbroughV(2013)Theeffectofintranasaloxytocintreatmentonconditionedfearextinctionandrecallinahealthyhumansample.Psychopharmacology(Berl)229:199-208.
![Page 21: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/21.jpg)
17
AmericanPsychiatricAssociation.(2013).Diagnosticandstatisticalmanualofmentaldisorders:DSM-5.Washington,D.C:AmericanPsychiatricAssociation.
AyersLW,MissigG,SchulkinJ,RosenJB(2011)Oxytocinreducesbackgroundanxietyinafear-potentiatedstartleparadigm:Peripheralvscentraladministration.Neuropsychopharmacology36:2488-2497.
BakerDG,NievergeltCM,RisbroughVB(2009)Post-traumaticstressdisorder:Emergingconceptsofpharmacotherapy.ExpertOpiniononEmergingDrugs14:251-272.
Bakermans-KranenburgM,VanIJzendoornM(2013)Sniffingaroundoxytocin:Reviewandmeta-analysesoftrialsinhealthyandclinicalgroupswithimplicationsforpharmacotherapy.TranslationalPsychiatry3:e258.
BethlehemRA,vanHonkJ,AuyeungB,Baron-CohenS(2013)Oxytocin,brainphysiology,andfunctionalconnectivity:AreviewofintranasaloxytocinfMRIstudies.Psychoneuroendocrinology38:962-974.
BhatnagarS,ViningC,IyerV,KinniV(2006)ChangesinHypothalamic-Pituitary-Adrenalfunction,bodytemperature,bodyweightandfoodintakewithrepeatedsocialstressexposureinrats.JNeuroendocrinol18:13-24.
BirurB,MooreNC,DavisLL(2017)Anevidence-basedreviewofearlyinterventionandpreventionofposttraumaticstressdisorder.CommunityMentHealthJ53:183-201.
BurkeHM,RobinsonCM,WentzB,McKayJ,DexterKW,PisanskyJM,TalbotJN,ZoladzPR(2013)Sex-specificimpairmentofspatialmemoryinratsfollowingareminderofpredatorstress.Stress16:469-476.
CookMN,CrounseM,FlahertyL(2002)Anxietyintheelevatedzero-mazeisaugmentedinmiceafterrepeateddailyexposure.BehavGenet32:113-118.
![Page 22: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/22.jpg)
18
CoxE,StuebeA,PearsonB,GrewenK,RubinowD,Meltzer-BrodyS(2015)OxytocinandHPAstressaxisreactivityinpostpartumwomen.Psychoneuroendocrinology55:164-172.
DaskalakisNP,LehrnerA,YehudaR(2013)Endocrineaspectsofpost-traumaticstressdisorderandimplicationsfordiagnosisandtreatment.EndocrinolMetabClinNorthAm42:503-513.
DawsonGR,TricklebankMD(1995)Useoftheelevatedplusmazeinthesearchfornovelanxiolyticagents.TrendsPharmacolSci16:33-36.
DeKloetC,VermettenE,GeuzeE,KavelaarsA,HeijnenC,WestenbergH(2006)AssessmentofHPA-axisfunctioninposttraumaticstressdisorder:Pharmacologicalandnon-pharmacologicalchallengetests,areview.JPsychiatrRes40:550-567.
DingessPM,DarlingRA,DermanRC,WulffSS,HunterML,FerrarioCR,BrownTE(2017)Structuralandfunctionalplasticitywithinthenucleusaccumbensandprefrontalcortexassociatedwithtime-dependentincreasesinfoodcue-seekingbehavior.Neuropsychopharmacology.
EngertV,KoesterAM,RiepenhausenA,SingerT(2016)Boostingrecoveryratherthanbufferingreactivity:Higherstress-inducedoxytocinsecretionisassociatedwithincreasedcortisolreactivityandfastervagalrecoveryafteracutepsychosocialstress.Psychoneuroendocrinology74:111-120.
EnnaceurA,MichalikovaS,ChazotP(2006)Modelsofanxiety:Responsesofratstonoveltyinanopenspaceandanenclosedspace.BehavBrainRes171:26-49.
ErmischA,RühleH,LandgrafR,HessJ(1985)Blood—brainbarrierandpeptides.JournalofCerebralBloodFlow&Metabolism5:350-357.
![Page 23: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/23.jpg)
19
FeboM,FerrisCF(2014)Oxytocinandvasopressinmodulationoftheneuralcorrelatesofmotivationandemotion:ResultsfromfunctionalMRIstudiesinawakerats.BrainRes1580:8-21.
FernandesC,GonzalezM,WilsonC,FileSE(1999)Factoranalysisshowsthatfemaleratbehaviourischaracterizedprimarilybyactivity,maleratsaredrivenbysexandanxiety.PharmacologyBiochemistryandBehavior64:731-736.
Fischer-ShoftyM,Shamay-TsooryS,HarariH,LevkovitzY(2010)Theeffectofintranasaladministrationofoxytocinonfearrecognition.Neuropsychologia48:179-184.
FrijlingJL,vanZuidenM,KochSB,NawijnL,GoslingsJC,LuitseJS,BiesheuvelTH,HonigA,BakkerFC,DenysD(2014)EfficacyofoxytocinadministrationearlyafterpsychotraumainpreventingthedevelopmentofPTSD:Studyprotocolofarandomizedcontrolledtrial.BMCPsychiatry14:92.
GaoJ,WangH,LiuY,LiYY,ChenC,LiuLM,WuYM,LiS,YangC(2014)GlutamateandGABAimbalancepromotesneuronalapoptosisinhippocampusafterstress.MedSciMonit(UnitedStates)20:499-512.
GaoY,LiC,shenJ,YinH,AnX,JinH(2011)Effectoffoodazodyetartrazineonlearningandmemoryfunctionsinmiceandrats,andthepossiblemechanismsinvolved.JFoodSci76:T125-T129.
GerritsenL,MilaneschiY,VinkersC,vanHemertB,vanVelzenL,SchmaalL,PenninxBW(2017)HPAaxisgenes,andtheirinteractionwithchildhoodmaltreatment,arerelatedtocortisollevelsandstress-relatedphenotypes.Neuropsychopharmacology(England).
GuastellaAJ,EinfeldSL,GrayKM,RinehartNJ,TongeBJ,LambertTJ,HickieIB(2010)Intranasaloxytocinimprovesemotionrecognitionforyouthwithautismspectrumdisorders.BiolPsychiatry67:692-694.
HallC,BallacheyEL(1932)Astudyoftherat'sbehaviorinafield.Acontributiontomethodincomparativepsychology.UniversityofCaliforniaPublicationsinPsychology.
![Page 24: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/24.jpg)
20
HallJM,PodawiltzA,MummertDI,JonesH,MummertME(2012)Psychologicalstressandthecutaneousimmuneresponse:RolesoftheHPAaxisandthesympatheticnervoussysteminatopicdermatitisandpsoriasis.DermatologyResearchandPractice2012:.
HeinrichsM,DomesG(2008)Neuropeptidesandsocialbehaviour:Effectsofoxytocinandvasopressininhumans.ProgBrainRes170:337-350.
HeinrichsM,BaumgartnerT,KirschbaumC,EhlertU(2003)Socialsupportandoxytocininteracttosuppresscortisolandsubjectiveresponsestopsychosocialstress.BiolPsychiatry54:1389-1398.
JanezicEM,UppalapatiS,NaglS,ContrerasM,FrenchED,FellousJ(2016)Beneficialeffectsofchronicoxytocinadministrationandsocialco-housinginarodentmodelofpost-traumaticstressdisorder.BehavPharmacol27:704-717.
KilpatrickDG,ResnickHS,MilanakME,MillerMW,KeyesKM,FriedmanMJ(2013)NationalestimatesofexposuretotraumaticeventsandPTSDprevalenceusingDSM-IVandDSM-5criteria.JTraumaStress26:537-547.
LevyA(2001)Ananimalmodelforstudyingtherapeuticdrugsagainstpost-traumaticstressdisorder.MilMed166:74.
LoveTM(2014)Oxytocin,motivationandtheroleofdopamine.PharmacologyBiochemistryandBehavior119:49-60.
MissigG,AyersLW,SchulkinJ,RosenJB(2010)Oxytocinreducesbackgroundanxietyinafear-potentiatedstartleparadigm.Neuropsychopharmacology35:2607-2616.
MorenaM,BerardiA,PelosoA,ValeriD,PalmeryM,TrezzaV,SchellingG,CampolongoP(2017)Effectsofketamine,dexmedetomidineandpropofol
![Page 25: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/25.jpg)
21
anesthesiaonemotionalmemoryconsolidationinrats:Consequencesforthedevelopmentofpost-traumaticstressdisorder.BehavBrainRes329:215-220.
NawijnL,vanZuidenM,KochSB,FrijlingJL,VeltmanDJ,OlffM(2016)Intranasaloxytocinenhancesneuralprocessingofmonetaryrewardandlossinpost-traumaticstressdisorderandtraumatizedcontrols.Psychoneuroendocrinology.
NawijnL,vanZuidenM,FrijlingJL,KochSB,VeltmanDJ,OlffM(2015)RewardfunctioninginPTSD:Asystematicreviewexploringthemechanismsunderlyinganhedonia.Neuroscience&BiobehavioralReviews51:189-204.
NeumannID,MaloumbyR,BeiderbeckDI,LukasM,LandgrafR(2013)Increasedbrainandplasmaoxytocinafternasalandperipheraladministrationinratsandmice.Psychoneuroendocrinology38:1985-1993.
NicolaSM(2016)Reassessingwantingandlikinginthestudyofmesolimbicinfluenceonfoodintake.AmJPhysiolRegulIntegrCompPhysiol(UnitedStates)311:R811-R840.
PellowS,ChopinP,FileSE,BrileyM(1985)Validationofopen:Closedarmentriesinanelevatedplus-mazeasameasureofanxietyintherat.JNeurosciMethods14:149-167.
PeralsD,GriffinAS,BartomeusI,SolD(2017)Revisitingtheopen-fieldtest:Whatdoesitreallytellusaboutanimalpersonality?AnimBehav123:69-79.
PhelpsEA(2006)Emotionandcognition:Insightsfromstudiesofthehumanamygdala.AnnuRevPsychol57:27-53.
PiantadosiPT,YeatesDC,WilkinsM,FlorescoSB(2017)Contributionsofbasolateralamygdalaandnucleusaccumbenssubregionstomediatingmotivationalconflictduringpunishedreward-seeking.NeurobiolLearnMem140:92-105.
![Page 26: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/26.jpg)
22
PrutL,BelzungC(2003)Theopenfieldasaparadigmtomeasuretheeffectsofdrugsonanxiety-likebehaviors:Areview.EurJPharmacol463:3-33.
Renicker,MD,Cysewski,NG,Palmer,SM,Nakonechnyy,DV,Keef,AJ,andDaberkow,DP(2015)Behavioralandphysiologicaleffectsofoxytocintreatmentinaratmodelofpost-traumaticstressdisorder.SocietyforNeurosciencemeetingabstract
RodgersR,DalviA(1997)Anxiety,defenceandtheelevatedplus-maze.Neuroscience&BiobehavioralReviews21:801-810.
RothbaumBO,KearnsMC,ReiserE,DavisJS,KerleyKA,RothbaumAO,MercerKB,PriceM,HouryD,ResslerKJ(2014)EarlyinterventionfollowingtraumamaymitigategeneticriskforPTSDincivilians:Apilotprospectiveemergencydepartmentstudy.JClinPsychiatry(UnitedStates)75:1380-1387.
SackM,SpielerD,WizelmanL,EppleG,StichJ,ZabaM,SchmidtU(2017)Intranasaloxytocinreducesprovokedsymptomsinfemalepatientswithposttraumaticstressdisorderdespiteexertingsympathomimeticandpositivechronotropiceffectsinarandomizedcontrolledtrial.BMCMedicine15:40.
SahraeiH,FatahiZ,EidiA,Haeri-RohaniA,HooshmandiZ,ShekarforoushS,TavalaeiSA(2012)Inhibitingposttraumaticstressdisorder(PTSD)inducedbyelectricshockusingethanolextractofsaffroninrats.J.Biol.Res.Thessalon18:320-327.
SestakovaN,PuzserovaA,KluknavskyM,BernatovaI(2013)Determinationofmotoractivityandanxiety-relatedbehaviourinrodents:Methodologicalaspectsandroleofnitricoxide.InterdisciplinaryToxicology6:126-135.
ShepherdJK,GrewalSS,FletcherA,BillDJ,DourishCT(1994)Behaviouralandpharmacologicalcharacterisationoftheelevated“zero-maze”asananimalmodelofanxiety.Psychopharmacology(Berl)116:56-64.
![Page 27: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/27.jpg)
23
SmithAS,WangZ(2014)Hypothalamicoxytocinmediatessocialbufferingofthestressresponse.BiolPsychiatry76:281-288.
SteinDJ,McLaughlinKA,KoenenKC,AtwoliL,FriedmanMJ,HillED,MaerckerA,PetukhovaM,ShahlyV,OmmerenM(2014)DSM-5andICD-11definitionsofposttraumaticstressdisorder:Investigating“narrow”and“broad”approaches.DepressAnxiety31:494-505.
StevensFL,WiesmanO,FeldmanR,HurleyRA,TaberKH(2013)Oxytocinandbehavior:Evidenceforeffectsinthebrain.JNeuropsychiatryClinNeurosci25:96-102.
StockhorstU,AntovMI(2015)Modulationoffearextinctionbystress,stresshormonesandestradiol:Areview.FrontiersinBehavioralNeuroscience9:.
StriepensN,KendrickKM,HankingV,LandgrafR,WüllnerU,MaierW,HurlemannR(2013)Elevatedcerebrospinalfluidandbloodconcentrationsofoxytocinfollowingitsintranasaladministrationinhumans.ScientificReports3:3440.
TalegaonkarS,MishraP(2004)Intranasaldelivery:Anapproachtobypassthebloodbrainbarrier.IndianJournalofPharmacology36:140.
TaylorSE,GonzagaGC,KleinLC,HuP,GreendaleGA,SeemanTE(2006)Relationofoxytocintopsychologicalstressresponsesandhypothalamic-pituitary-adrenocorticalaxisactivityinolderwomen.PsychosomMed(UnitedStates)68:238-245.
TuckerLB,McCabeJT(2017)BehaviorofmaleandfemaleC57BL/6Jmiceismoreconsistentwithrepeatedtrialsintheelevatedzeromazethanintheelevatedplusmaze.FrontiersinBehavioralNeuroscience11:.
VaivaG,DucrocqF,JezequelK,AverlandB,LestavelP,BrunetA,MarmarCR(2003)Immediatetreatmentwithpropranololdecreasesposttraumaticstressdisordertwomonthsaftertrauma.BiolPsychiatry54:947-949.
![Page 28: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/28.jpg)
24
vanBodegomM,HombergJR,HenckensMJ(2017)Modulationofthehypothalamic-pituitary-adrenalaxisbyearlylifestressexposure.FrontiersinCellularNeuroscience11:.
vanZuidenM,FrijlingJL,NawijnL,KochSB,GoslingsJC,LuitseJS,BiesheuvelTH,HonigA,VeltmanDJ,OlffM(2017)Intranasaloxytocintopreventposttraumaticstressdisordersymptoms:Arandomizedcontrolledtrialinemergencydepartmentpatients.BiolPsychiatry81:1030-1040.
VeeningJG,OlivierB(2013)Intranasaladministrationofoxytocin:Behavioralandclinicaleffects,areview.Neuroscience&BiobehavioralReviews37:1445-1465.
VerleyeM,GillardinJ(2004)Effectsofetifoxineonstress-inducedhyperthermia,freezingbehaviorandcolonicmotoractivationinrats.PhysiolBehav82:891-897.
WalshRN,CumminsRA(1976)Theopen-fieldtest:Acriticalreview.PsycholBull83:482.
WindleR,ShanksN,LightmanSL,IngramCD(1997)Centraloxytocinadministrationreducesstress-inducedcorticosteronereleaseandanxietybehaviorinrats1.Endocrinology138:2829-2834.
WiseRA,BozarthMA(1987)Apsychomotorstimulanttheoryofaddiction.PsycholRev94:469.
YehudaR,BiererLM(2009)TherelevanceofepigeneticstoPTSD:ImplicationsfortheDSM-V.JTraumaStress22:427-434.
YehudaR,DaskalakisNP,DesarnaudF,MakotkineI,LehrnerA,KochE,FloryJD,BuxbaumJD,MeaneyMJ,BiererLM(2013)Epigeneticbiomarkersaspredictors
![Page 29: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/29.jpg)
25
andcorrelatesofsymptomimprovementfollowingpsychotherapyincombatveteranswithPTSD.FrontiersinPsychiatry4:118.
YuH,WattH,KesavanC,JohnsonPJ,WergedalJE,MohanS(2012)Lastingconsequencesoftraumaticeventsonbehavioralandskeletalparametersinamousemodelforpost-traumaticstressdisorder(PTSD).PloSOne7:e42684.
ZoicasI,SlatteryDA,NeumannID(2014)Brainoxytocininsocialfearconditioninganditsextinction:Involvementofthelateralseptum.Neuropsychopharmacology39:3027-3035.
ZoladzPR,WoodsonJC,HaynesVF,DiamondDM(2010)Activationofaremote(1-yearold)emotionalmemoryinterfereswiththeretrievalofanewlyformedhippocampus-dependentmemoryinrats.Stress13:36-52.
Figures
Figure 1. Schematic diagram of open field enclosure and reward delivery area.
reward delivery tube
![Page 30: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/30.jpg)
26
Figure2.Ratintheenclosedareaoftheelevatedzeromaze.
Figure3.Timespentmotionless(freezing)during5minutere-exposuretothefootshockchamberfollowingoxytocinpretreatment(n=6,pergroup)weekonepoststress.OverallsignificantdifferencebyANOVAp<0.0001*significantlydifferentthanOxytocin+Stressp<0.05;+significantlydifferentthanControlandOxytocinp<0.05
+*
+
0
50
100
150
200
250
Control Oxytocin +Stress
Stress Oxytocin
Freezingtime(s)
![Page 31: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/31.jpg)
27
Figure4.Fecalproductionduring5minutere-exposuretothefootshockchamberfollowingoxytocinpretreatment(n=6,pergroup)weekonepoststress.OverallsignificancebyANOVAp<0.001;*significantlydifferentthanOxytocin+Stressp<0.05;+significantlydifferentthanControlandOxytocinp<0.05
Figure5.Timespentintheopenarmduring5-minuteexposuretotheelevatedzeromazefollowingoxytocinpretreatment(n=6,pergroup)weekonepoststress.Therewasnosignificantdifferencebetweenthegroupsp=0.15
+*
+
00.20.40.60.81
1.21.41.61.8
Control Oxytocin +Stress
Stress Oxytocin
Feces(g)
0
10
20
30
40
50
60
Control Oxytocin +Stress
Stress Oxytocin
Opentime(s)
![Page 32: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/32.jpg)
28
Figure6.Averagetimeacross3trialstoretrievefoodreward(FrootLoop)inopenfieldenclosurefollowingoxytocinpretreatment(n=6,pergroup)weekonepoststress.Therewasnosignificantdifferencebetweengroupsp=0.47
Figure7.Timespentmotionless(freezing)during5-minutere-exposuretothefootshockchamberfollowingoxytocinpretreatment(n=6,pergroup),weektwopoststress.OverallsignificancefromANOVAp<0.0005
0
5
10
15
20
25
30
35
40
45
Control Oxytocin +Stress
Stress Oxytocin
AverageRetrievalTime(s)
+
020406080100120140160180
Control Oxytocin +Stress
Stress Oxytocin
Freezing
time(s)
![Page 33: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/33.jpg)
29
+significantlydifferentthanControlandOxytocinp<0.05
Figure8.Fecalproductionduring5-minutere-exposuretothefootshockchamberfollowingoxytocinpretreatment(n=6,pergroup),weektwopoststress.Overall,p=0.016;+significantlydifferentthanControlandOxytocinp<0.05
Figure9.Timespentintheopenarmduring5minuteexposuretotheelevatedzeromazefollowingoxytocinpretreatment(n=6,pergroup)twoweekspoststress.Therewasnooverallsignificancebetweengroupsp=0.68.
+
0
0.2
0.4
0.6
0.8
1
1.2
1.4
Control Oxytocin +Stress
Stress Oxytocin
Feces(g)
0
10
20
30
40
50
Control Oxytocin +Stress
Stress Oxytocin
Opentime(s)
![Page 34: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/34.jpg)
30
Figure10.Timetoretrievefoodreward(FrootLoop)inopenfieldenclosurefollowingoxytocinposttreatmentpretreatment(n=6,pergroup)twoweekspoststress.p=0.55
Figure11.Comparisonoffreezingtimesbetweenweek1andweek2inStressandOxytocin+Stressgroups.
*p<0.05two-tailedt-test
*
0
50
100
150
200
250
Stress Oxytocin+Stress
FreezingTime(s)
Week1
Week2
0
5
10
15
20
25
30
35
Control Oxytocin +Stress
Stress Oxytocin AverageRetrievalTime(s)
![Page 35: IMPACT OF PROPHYLACTIC INTRANASAL OXYTOCIN …](https://reader031.vdocuments.site/reader031/viewer/2022012514/618d96f66d038654024da8d5/html5/thumbnails/35.jpg)
31
VITA
Author:MorganA.Thomas,néePowell
PlaceofBirth:Spokane,Washington
UndergraduateSchoolsAttended:UniversityofWashington
DegreesAwarded:BachelorofScience,2013,UniversityofWashington
HonorsandAwards:GraduateFellowship,BiologyDepartment,2015-2017,EasternWashingtonUniversity
BiologyDepartmentMiniGrant,2017,EasternWashingtonUniversity
ProfessionalExperience:
AnatomyandPhysiologyTeachingAssistant,EasternWashingtonUniversityBiologyDepartment,2015-2017
SeniorCapstoneTeachingAssistant,EasternWashingtonUniversityBiologyDepartment,2016
DataCoordinator,FredHutchinsonCancerResearchCenter,2013-2015
SportsMedicineIntern,UniversityofWashingtonAthletics,2010-2013