Download The Neurobiology of Ecstasy (MDMA)

NationalInstituteonDrugAbuse(NIDA)
TheNeurobiologyofEcstasy(MDMA)
LastUpdatedJanuary2007
https://www.drugabuse.gov
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TableofContents
TheNeurobiologyofEcstasy(MDMA)
SectionI
SectionII
SectionIII
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SectionI
1:Introduction:long-termeffectsof
ecstasy
Aneffectivewayofstartingapresentationistopresentsomethinginterestingor
provocative.Thisfirstimageshowssectionstakenfromtheneocortexof
monkeysthatweregivenecstasytwiceadayfor4days(controlmonkeyswere
givensaline).Thesectionontheleft,takenfromthebrainofacontrolmonkey,
showsthepresenceofalotofserotonin.Themiddlesectionshowsasection
fromamonkeytwoweeksafterreceivingecstasy.Pointoutthatmostofthe
serotoninisgone.Thesectionontherightshowsasectionfromamonkey
sevenyearsafterreceivingecstasy.Pointoutthatalthoughtherehasbeen
somerecoveryofserotonin,thebrainstillhasnotreturnedtonormal.Indicate
thatyouwilldiscussthisinyourtalkinmoredetail.Introducethepurposeof
yourpresentation.Indicatethatyouwillexplainhowecstasyinteractswith
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specifictargetsinthebrainandwhatcanhappenafterrepeatedorlong-term
use.Tellthestudentsthatyouwillreviewhowneuronscommunicatewitheach
otherandhowecstasyaltersthiscommunication,resultinginchangesinmood,
behavior,andmemory.
2:Defineecstasy
Ecstasyisaderivativeofamphetamine(showninpurpleontheimage).Its
chemicalnameis3,4-methylenedioxymethamphetamine(MDMA)andithasa
similarstructuretomethamphetamine.ecstasyhasavarietyofstreetnames
including,XTC,Adam,M&M,E,andessence.Explaintostudentsthatecstasy
isunlikeotherdrugsofabuse,whichareoftenderivedfromplants(e.g.,
cocaine,morphine,nicotine).Incontrast,ecstasyissynthesizedinclandestine
laboratories--infact,thereareseveral"designerdrugs"thataremade(in
clandestinelaboratories)byalteringthestructureoftheamphetaminemolecule.
Becauseecstasyissynthesizedinlaboratories,itspuritycanvarysubstantially
fromlabtolab,andothercompoundsareeasilycombinedintothesametablet
(contaminantsoftenincludecaffeine,ephedrine,ketamine-amildhallucinogen
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andmethamphetamine).
3:Ecstasygetsintothebraineasily
Thechemicalstructureofecstasyallowsittoreachthebrainquicklyafter
ingestion.Usetheimagetoillustratetothestudentsthepathwaythatecstasy
followsfromthemouthtothebrain.First,thepillisingestedanditdisintegrates
quicklyinthestomachcontents.Oncedissolved,someecstasymoleculesare
absorbedfromthestomachintothebloodstream,butmostoftheecstasy
moleculesmovefromthestomachintothesmallintestine.There,theyare
absorbedintothebloodstreamveryeasily.
Thefollowingexplanationisoptionalandmaybedesirableforpresentationto
studentswhohavehadsomechemistry:ecstasyisaweakbase--thismeans
thatecstasyislikelyto"pickup"oracceptahydrogenion(H+)fromthe
surroundingmedium(thegastricacidinthestomachisloadedwithH+).After
theecstasyhasacceptedaH+,ithasacharged(orpolar)character,which
makesitdifficulttocrossabiologicalmembrane.Biologicalmembraneshavea
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nonpolarcore,socompoundshavinganonpolarnaturearemorelikelyto
diffuseacrossthemembrane(passivediffusion).Therefore,mostoftheecstasy
isnotabsorbedfromthestomachintothebloodstream.Rather,theecstasy
moleculesgetemptiedfromthestomachintothesmallintestine.Inthesmall
intestinethemorealkalineenvironmentcausesecstasytogiveupitsH+,
becomingmorenonpolar.Thelargesurfaceareaandthemorealkaline
environmentenabletheecstasymoleculestodiffuseacrossthemembraneinto
thebloodcapillariesveryquickly.
Ecstasymoleculesthathaveenteredthebloodstreamfromthestomachand
smallintestinesthentraveltotheliver(shownbythebottombluearrows).Inthe
liver,someoftheecstasyismetabolizedtoinactivecompoundsandtherestis
carriedthroughtheveinstotheheart(bluearrow).Onceintheheart,the
ecstasyispumpedtothelungsalongwiththeblood,whichbecomes
oxygenatedandthenreturnstotheheart(redarrow).Now,oxygenatedblood
carriestheecstasyfromthehearttothebrain(redarrow)andtootherorgansin
bodythathaveahighbloodflow.Normallythereisabarrierbetweentheblood
vesselsinthebrainandbrainmatter,whichexcludesmanydrugsfromentering
thebrain.However,ecstasyispredominantlyinitsnonpolarforminbloodand
thereforeitcrossesthebarrierintothebrainveryeasily.Itwilltakeabout15
minutesforecstasytoreachthebrainiftakenonanemptystomach.
4:Whatweknowaboutecstasy
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Inrecentyears,therehasbeenalotofresearchcarriedouttounderstandhow
ecstasyaffectsthebrain.Scientistshavemadealotofprogressinidentifying
howecstasychangesmoodandbehavior.Indicatetostudentsthatecstasyhas
short-termandlong-termeffectsonthebrain.Theshort-termeffectsofecstasy
includechangesinbrainchemistryandbehavior.Thelong-termeffectsinclude
changesinbrainstructure(basedmainlyonanimalstudies)andbehavior.Tell
themthatyouwilltrytoillustratehowthesechangestakeplace.Youcouldask
studentsiftheyhaveanyknowledgeoftheshort-termorlong-termeffectsof
ecstasyonthebrain.Iftheyvolunteersomeanswers,listthemontheboard;
indicatethatyouwilldiscusshowsomeoftheseeffectsareproduced.
5:Howdoweknow?Researchinanimals
andhumans
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Bringuptheimportanceofanimalsinresearch.Researchinanimalshas
provideduswithadetailedunderstandingabouttheactionsofecstasyinthe
brain.Infact,manyoftheresearchfindingsobtainedfromanimals,suchasrats
andmonkeys,havenowbeenreplicatedinhumans.Indicatetothestudents
thatanotherimportantaspectofusinganimalsinresearchistounderstand
mechanismsfortoxicityproducedbycompounds.ecstasyisaclassicexample
ofadrugthatproducestoxicity(inthebrain)anditwouldbeimpossibletostudy
thisinlivinghumans.Inthefollowingsetofimages,theinformationhighlighting
howecstasyworkswasobtainedfromresearchusinganimals.
6:Brainareassensitivetoecstasy
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Beforeexplaininghowecstasyworks,itmaybehelpfultopointouttheareasof
thebrainthataresensitivetotheeffectsofecstasy.ecstasyaffectscognition
(thinking),mood,andmemory.Italsocancauseanxietyandaltered
perceptions(similartobutnotquitethesameashallucinations).Themost
desirableeffectofecstasyisitsabilitytoprovidefeelingsofwarmthand
empathy.Tellstudentsthatyouwilltalkabouttheeffectsofecstasyinmore
detailinafewminutes.Thereareseveralpartsofthebrainthatareimportantin
theseactionsofecstasy.Pointtotheneocortex(inyellow),whichisimportantin
cognition,memory,andalteredperceptions.Pointtotheseveralstructuresdeep
inthebrainthatmakeupthelimbicsystem(e.g.,theamygdala(red),
hippocampus(blue),basalganglia(purple),andhypothalamus(green),which
isinvolvedinchangesinmood,emotions,andtheproductionofanxiety(the
hippocampusisalsoinvolvedinmemory).Scientistsdonotknowyetwhich
areaofthebrainisinvolvedintheabilityofecstasytogeneratefeelingsof
empathy(youcouldaskstudentstosuggestwheretheythinkecstasymightdo
this-limbicareasareagoodguess).
7:Anatomyofaneuron
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Nowthatthestudentsknowthattherearespecificregionsofthebrainaffected
byecstasy,youwillneedtodescribehowitworks.First,indicatethatthe
differentregionsofthebrainareconnectedbynervecellsorneuronsvia
pathways.Thesepathwaysofneuronssendandintegrateinformation
(electricalandchemical).Describetheneuronusingtheschematicinthis
image.Thecellbody,whichcontainsthenucleus,isthecenterofactivity.
Dendritesreceivechemicalinformationfromotherneuronsthatisconvertedto
electricalsignalswhichtraveltowardthecellbody.Whenthecellbodyreceives
enoughelectricalsignalstoexciteit,alargeelectricalimpulseisgeneratedand
ittravelsdowntheaxontowardtheterminal.Intheterminalarea,chemicals
calledneurotransmittersarereleasedfromtheneuroninresponsetothearrival
ofanelectricalsignal.Tellthestudentsthatyouwillexplainthisinmoredetail,
usingtheneurochemicalserotoninasanexample.
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SectionII
1:Howdoesecstasywork:serotonin
pathwaysinthebrain
Thenervepathwaythatispredominantlyaffectedbyecstasyiscalledthe
serotoninpathway.Serotoninisaneurotransmitterthatissynthesized,stored,
andreleasedbyspecificneuronsinthispathway.Itisinvolvedintheregulation
ofseveralprocesseswithinthebrain,includingmood,emotions,aggression,
sleep,appetite,anxiety,memory,andperceptions.Tellthestudentsthatyouwill
showthemhowachemicallikeserotonincanregulatetheseprocesses.First,
describehowserotoninpathwaysinnervate(connectto)differentbrainregions.
Pointtothecellbodiesoftheserotoninpathwaythatarelocatedinthe
brainstemarea"theRaphenucleus"inpink).Showstudentshowtheseneurons
sendlongaxonstohighercentersinthebrainincludingtheneocortex(yellow)
andthelimbicsystem(e.g.,theamygdala--redandhippocampus--blue).Point
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toasecondpathwayforserotoninneuronsthatdescendsdownthespinalcord;
theseneuronscontrolmuscleactivity;tellthestudentsthatyouwilltalkabout
thisinmoredetailinafewminutes.Indicatethatthefunctionofserotonin
dependsontheregionofthebrainintowhichitisreleased(italsodependson
thetypeofserotoninreceptorpresentinthatregion--seediscussioninimage9).
Forexample,theserotoninneuronsintheneocortexinthefrontofthebrain
(frontalcortex)regulatecognition,memory,andperceptions.Theserotonin
neuronsinthehippocampusregulatememory.Theserotoninneuronsinother
limbicareassuchastheamygdalaalsoregulatemood.
2:Theserotoninneuron:themajortarget
ofecstasy
Inordertohelpstudentsunderstandhowecstasyaffectsthefunctionof
serotoninneurons,itwillbeusefultoreviewhowneurotransmissiontakesplace
inalittlemoredetail.Youcanexplainserotoninneurotransmissionasan
example(serotoninisoneofmanyneurotransmitters).Thisimageshowsthe
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connectionbetweentwoneurons(the"synapse").Serotoninisstoredinsmall
vesicleswithinthenerveterminalofaneuron.Electricalimpulses(arisinginthe
Raphenucleus,forexample)travelingdowntheaxontowardtheterminal
causethereleaseofserotoninfromsmallvesiclesintothesynapticspace.Point
tothespacebetweentheterminalandtheneighboringneuron.Wheninthe
synapticspace,theserotoninbindstospecialproteins,calledreceptors,onthe
membraneofaneighboringneuron(thisisusuallyatadendriteorcellbody).
Whenserotoninbindstoserotoninreceptors(thereareactuallyatleast14types
ofserotoninreceptors),itcausesachangeintheelectricalpropertiesofthe
receivingneuronthatgenerallyresultsinadecreaseinitsfiringrate.Gotothe
nextimagetoexplainhowtheactionofserotoninisterminated.
3:Serotonintransporters
Serotonin(inpink)ispresentinthesynapticspaceonlyforalimitedamountof
time.Ifitisnotboundtotheserotoninreceptor,serotoninisremovedfromthe
synapticspaceviaspecialproteinscalledtransporters(ingreen).Theserotonin
transportersareproteinslocatedontheserotoninneuronterminalsandthey
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areinauniquepositiontotransportserotoninfromthesynapticspacebackinto
theneuronwhereitcanbemetabolizedbyenzymes.Explaintoyourstudents
thattheserotonintransportersaretheprimarytargetsforecstasy.
4:Ecstasyandserotonintransporters
Whenecstasybindstotheserotonintransporters,moreserotoninendsupinthe
synapticspace.Thisoccursfortworeasons.First,ecstasycanpreventthe
transportersfromcarryingserotoninbackintotheterminal.Second,ecstasycan
causethetransporterstoworkinreversemode--theyactuallybringserotonin
fromtheterminalintothesynapticspace.So,moreserotoninispresentinthe
synapticspaceandmoreserotoninreceptorsbecomeactivated.Thisisthe
majorshort-termeffectofecstasythataltersbrainchemistry.Althoughthe
serotoninsystemistheprimarytargetforecstasy,ecstasyhassimilareffectson
thedopamine(anotherneurotranmsitter)systemaswell.ecstasycaninhibit
dopaminetransportersandcauseanincreaseindopaminelevelsinthe
synapticspace(notshownhere).Tohelpstudentsunderstandhowthe
alterationinbrainchemistryresultsinpsychologicalchanges,gotothenext
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image.
5:Short-term(acute)effectsofecstasy
Explainthatwhenapersonusesecstasy,theincreaseinserotoninindifferent
brainregions(i.e.,theareaswhereserotoninneuronstravelingfromtheraphe
nucleusterminate)causespsychologicaleffects.Theseincludeelevatedmood
andfeelingsofempathy.Theecstasyisalsoreinforcing,whichmeansthatits
pleasurablepropertiesincreasethelikelihoodthatthepersonwilltakeitagain.
Tellthestudentsthatdrugsthatarereinforcingareusuallyaddictive.
Studentsmightaskyouifecstasyisaddictive.Scientistsandhealth
professionalsdon'thaveadefinitiveansweryet.Fornowthereareseveral
piecesofevidencethatsuggestthatecstasyhasthepotentialtobeaddictive.In
onestudyofecstasyusers,43%ofrespondentsmetcriteriathatarecommonly
usedtodeterminedependenceforotherdrugsofabuse.Thisincluded
symptomssuchascontinuingtousethedrugdespiteknowledgeofphysicalor
psychologicalharm,experiencingwithdrawaleffects,andtolerance(or
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diminishedresponse)torepeateduseofecstasy.Inaresearchsetting,
monkeyswilladministerecstasytothemselves(theyactuallypressaleverto
obtainaninjection),justastheydoforotheraddictivedrugs.Monkeyswillnot
self-administerdrugsthatarenotaddictive.Inaddition,thereisemerging
researchtoshowthatecstasyhasactionsinaspecificpathwaywithinthelimbic
systemcalledthe"rewardpathway",whichcanexplainit'sreinforcingeffects.In
fact,alladdictivedrugsactinsomewaywithinthe"rewardpathway".Formore
informationonthis,seetheNIDATeachingPacketreferencedattheend.
Manyofthepsychologicaleffectsofecstasyareduetoitsactionswithinthe
limbicsystem(theamygdala,inred,andhippocampus,inblue,especially).The
abilityofecstasytoproducemildstimulationisduetoitsactionsinanotherpart
ofthelimbicsystem--thebasalganglia(inpurple).Itisherewhereecstasy's
effectsonthedopaminesystemmaybeimportant.Theheightenedperceptions
involvetheactionsofecstasyintheneocotex(inyellow).ecstasycanalso
reducetheappetite,becauseitactsinthehypothalamus(ingreen),which
controlsfeedingbehavior.
6:Short-termadverseeffects
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Peoplewhotakeecstasydesireitspleasurableorreinforcingeffects(just
describedinthelastimage).However,fewdrugsareabletoproducedesirable
effectswithoutalsoproducingsideeffects.ecstasyisnoexception,andthere
areseveralsideeffectsoradverseeffectsthatcanoccur,especiallyathigh
doses.However,somepeoplewhotakeonlyoneecstasypillmayhave
negativepsychologicaleffectssuchascloudedthinking,agitation,and
disturbedbehavior.Pointtoareasofthebrainwhereecstasymayproduce
theseadverseeffects(theneocortex,inyellowandlimbicstructures,inredand
blue).Otheradverseeffectscanoccuraswell.Theseincludesweating,dry
mouth(thirsty),increasedheartrate,fatigue,musclespasms(especiallyjawclenching)andhyperthermia.Inthelattercase,ecstasycandisrupttheabilityof
thebraintoregulatebodytemperature.Thisusuallyresultsinhyperthermia,
especiallywhentheuserisinahotenvironmentand/orengaginginintense
physicalactivitysuchasfastdancingat"rave"parties.Youcanprovidesome
examplestoshowwhereecstasyproducesthesesideeffects.Forexample,the
developmentofthirstandthehyperthermiaareduetoactionsofecstasyinthe
hypothalamus(green),whichcontrolsdrinkingbehaviorandbodytemperature.
Youmightpointoutthattheeffectofecstasyonthehypothalamuscauses
multipleeffectsinthebody,andinsomecasestheyareverydangerous(see
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thenextimage).Themusclespasmsandjaw-clenchingareduetoecstasy's
actionatthemotorneuronsinthespinalcord(inyellow)(remindthestudents
thatamajorserotoninpathwaydescendsdownthespinalcord).Themotor
neuronssendsignalstothemusclestocontract.
7:Life-threateningeffectsaftermultiple
dosesor"stacking"
Somepeopletakemultipledosesofecstasyinonenight("stacking").Thismight
beduetothereinforcingeffectofthedrugwearingoffovertime.Often,if
somethingfeelsgood,onewantstodoitagain!Unfortunately,increaseddoses
alsoincreasetheadverseeffects,andsomeofthesecanbecomelifethreatening.Forexample,repeateddosesorahighdoseofecstasycancause
heatinjuryduetohyperthermia,hypertension(highbloodpressure),cardiac
arrhythmias(irregularheartbeat),musclebreakdownandrenalfailuredueto
saltandfluiddepletion.Indicatethatthesedangerouseffectscanbeproduced
byecstasyactinginthebrain.Again,thehypothalamusisveryimportant,
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becauseitregulatesheartrateandbloodpressure,fluidretentionandkidney
functionand,ofcourse,bodytemperature.Ifthebodytemperaturegetstoohigh,
itcancausebraindamageorevenkillaperson.
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SectionIII
1:Short-termeffectsafterecstasyisgone
fromthebody
Ecstasyisanunusualdrugbecauseithaseffectsonthebrainthatdevelopand
persistforashorttimeafterthedrugiseliminatedfromthebody.Theseoften
includethedevelopmentofdepression-likefeelings,anxiety,restlessness,
irritability,andsleepdisturbances.These"aftereffects"occurbecauseofa
chemicalchangethattakesplaceattheserotoninsynapse.Toillustratehow
thisoccurs,thisimageshowstheserotoninsynapseduringandaftertaking
ecstasy.Threeconditionsareillustrated:ontheleft,neuronsnormallyrelease
serotonininresponsetoelectricalimpulses(basicallythereleaseisin"spurts").
Thisresultsinthenormalactivationofserotoninreceptors,whichkeepsour
psychologicalandphysiologicalfunctiononanevenkeel.So,forexample,we
haveanormalmoodandwearecalm.Inthemiddle,ecstasycausesa
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sustainedincreaseintheamountofserotonininthesynapticspace,leadingto
sustainedactivationofmoreserotoninreceptors.Thiscanproduceanelevated
mood(oreuphoria).Eventually,theserotoninneuronscan'tmakeserotoninfast
enoughtoreplacethatwhichwaslost,soonceEcstasyisgonefromthebody
(ontheright),lessserotoninisreleasedwitheachelectricalimpulseandfewer
serotoninreceptorsareactivated,producingdepression-likefeelingsand
anxiety.Anotherimportanteffectthatmayemergeaftertakingecstasyis
memorydisruption.(Askstudentsiftheycanfigureoutwhichareaofthebrainis
affectedhere;theanswershouldincludethecerebralcortexandthe
hippocampus).Thisisanadverseeffectthatmaypersistwithrepeatedorlongtermuseofecstasy.Indicatetostudentsthatthereissomeevidenceforthis
obtainedfromhumanstudies.
2:Long-termeffectsofecstasy:
neurotoxic?
WhenpeopleuseEcstasyrepeatedlyorlongterm,theremaybechangesin
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theirbrainchemistrythatsuggestthattheserotoninneuronsaredamaged.One
majorclueisthatserotoninitselfanditsmetabolites(remindstudentsthat
serotoninthatistakenbackupintotheterminalismetabolizedbyenzymes)are
diminishedinthebrainsofanimalstreatedwithecstasy.Moreover,thebest
evidencethatwehavesofaristhatevensevenyearsafterabriefexposureto
ecstasy,serotoninlevelsinmonkeybrainshavenotfullyreturnedtonormal.
Thisisdescribedinthenextimage.
3:Long-termeffectsinmonkeys
ImagecourtesyofDr.GARicaurte,JohnsHopkinsUniversitySchoolofMedicine.
Averyimportantexperimentwasperformedinmonkeystodetermineifecstasy
canactuallydamageneurons.Monkeysweregivenecstasytwiceadayforfour
days(controlmonkeysweregivensaline).Onegroupofmonkeys'brainswere
removedtwoweekslaterforanalysisandanothergroupofmonkeyslivedforan
additionalsevenyearsbeforetheirbrainswereremoved.Scientistsexamined
thebrainsforthepresenceofserotonin.Thisimageshowsthepresenceof
serotonininneuronsoftheneocortexfromthreetypicalmonkeys.Ontheleft,
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themonkeywhodidnotreceiveanyecstasyhadalotofserotonin(inpink)in
theneocortex.Twoweeksafteramonkeyreceivedecstasy,mostofthe
serotoninwasgone(pointtothemiddlepanel),suggestingthattheserotonin
neuronterminalsweredestroyed(therewasnodestructionoftheserotonincell
bodiesarisingbackinthebrainstem).Pointtotheright-handpanelandshow
studentsthatthisdamageappearedtobelong-termbecausesevenyearslater
therewassomerecovery,butitwasnotcomplete.Scientistsfoundsimilar
changesinlimbicareasofthebrainsuchasthehippocampusandamygdala.
Themonkeyexperimentsareanimportantreminderthathumansmaysufferthe
samefate,althoughthisstillremainstobedemonstrated.Tellthestudentshow
difficultitistodothissamekindofexperimentinhumans,becauseitrequires
removingpiecesofthebraintolookforthelossoftheserotoninneurons.
4:Ecstasycausesdegenerationof
serotoninnerveterminals
Thisimageillustratesthedegenerationofserotoninnerveterminalsafterlong-
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termorrepeateduseofecstasy(youcanreferbacktoimage9tocomparethis
degeneratingterminaltoahealthyterminal).Remindstudentsthatwehave
severalpiecesofevidencethatsupportthiseffectofecstasy.Experimentsin
animalsgivenecstasyindicatethatthiskindofdegenerationoccurs.Moreover,
somestudiesofhumanecstasyusersreportlessserotoninandserotonin
metabolitesinthecerebrospinalfluid(whichsurroundsandbathesthebrain
andspinalcord)comparedwithnonusers.Incontrast,theanimalstudies
indicatethattheserotonincellbodiesarestillintactbutthegeneticinstructions
fromthenucleusforanyregrowthoftheterminalsmaybeabnormal.
Althoughscientistsdonotyetknowforcertainhowecstasydamagesthe
serotoninterminalsintheseanimalstudies,someprogresshasbeenmadein
understandingthisprocess.Onemechanismisdamagethatinvolvesthe
productionofoxygenradicals(unstableformsofoxygen),whicharevery
destructivetoproteins,lipids,andDNA.Therichsupplyofmitochondria(which
areamajorsourceofoxygenradicalformation)foundintheterminalsmay
causetheterminalstobeespeciallysensitivetodrugslikeecstasy.
5:Long-termecstasyusemayimpair
memory
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Itisnotpossibletolookdirectlyatdamagedserotoninterminalsinliving
humans.Thebestevidencefordamagetoserotoninneuronsafterlong-termor
repeatedEcstasyuseinhumansistheassociationbetweentheneurochemical
andbehavioralchanges.Althoughmanybehavioralmeasureshavebeen
assessedinEcstasyusers(thelistisextensive),themostconsistentfindings
arethatsomechronicEcstasyusershaveverbalandvisualmemory
impairments.Researchisongoingtodetermineifthinkingabilityisdisruptedas
well.However,itisimportanttokeepinmindthatmanyusersofEcstasymay
unknowinglybetakingotherdrugsthataresoldasEcstasy,and/ortheymay
intentionallyuseotherdrugs,suchasmarijuana,whichmaycontributetothe
observeddeficitsinmemory.Additionally,moststudiesinpeopledonothave
measuresofmemoryabilityinEcstasyusersbeforetheybegantakingdrugs.
Therefore,itisdifficulttoruleoutpre-existingmemorydeficitsinEcstasyusers
comparedtononusers.Nevertheless,insomestudiesEcstasyuserswhohad
memoryimpairmentsalsohadlessserotoninmetabolitesorchangesinother
markersofserotoninfunction.Infact,severalstudieshaveshownthatthe
degreeofimpairmentorthechangesinmarkersofserotoninfunctionwere
relatedtotheextentofEcstasyuseoverthelifetime.Ontheimage,pointtothe
brainareasthatareinvolvedinthememoryimpairment-theneocortex(yellow)
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andthehippocampus(blue).[Asanaside,youcantellstudentsaninteresting
linkbetweenlowserotoninandmemoryimpairment:normalpeoplewhoarefed
adietthatcausesthemtosynthesizelessserotoninalsohavememory
impairment.]
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