ScienceDaily (Julayi 25, 2012) — Ukunyusa amanqanaba e-neurotransmitter dopamine kwi-cortex engaphambili yengqondo kunciphisa kakhulu impembelelo kubantu abadala abasempilweni, kuphononongo olwenziwe ngabaphandi kwiKliniki ye-Ernest Gallo kunye neZiko loPhando kwiYunivesithi yaseCalifornia, eSan Francisco.
"Impulsivity ngumngcipheko wokuba likhoboka lezinto ezininzi, kwaye kuye kwacetyiswa ukuba abantu abanamanqanaba asezantsi e-dopamine kwi-cortex yangaphambili bathanda ukungxama," utshilo umbhali okhokelayo u-Andrew Kayser, PhD, umphandi eGallo kunye nonjingalwazi oncedisayo. kwi-neurology kwi-UCSF. "Besifuna ukubona ukuba singakwazi ukwehlisa amandla ngokunyusa i-dopamine, kwaye kubonakala ngathi sinako."
Uphononongo lupapashwe ngoJulayi 4 kwiJenali ye-Neuroscience.
Kuphononongo oluphindwe kabini, olulawulwa yi-placebo, abathathi-nxaxheba be-23 abadala banikwe i-tolcapone, iyeza elivunyiweyo yi-Food and Drug Administration (FDA) evimbela i-enzyme ye-dopamine-degrading, okanye i-placebo. Emva koko abaphandi banika abathathi-nxaxheba umsebenzi olinganisa ukunyanzeliswa, bebacela ukuba benze ukhetho lwengcamango phakathi kokufumana imali encinci ngokukhawuleza ("incinci ngokukhawuleza") okanye isixa esikhulu kwixesha elizayo ("inkulu kamva"). Umthathi-nxaxheba ngamnye wavavanywa kabini, kanye nge-tolcapone kunye ne-placebo.
Abathathi-nxaxheba - ngakumbi abo babenomdla kakhulu kwisiseko - babenokuthi bakhethe ukhetho oluncinci "olukhulu emva kwexesha" emva kokuthatha i-tolcapone kunokuba babenjalo emva kokuthatha i-placebo.
I-imaging resonance yamagnetic eyenziwa ngelixa abathathi-nxaxheba babethatha uvavanyo luqinisekisile ukuba imimandla ye-cortex yangaphambili ehambelana nokuthatha isigqibo yayisebenza ngakumbi kubukho be-tolcapone kunokuba kubukho be-placebo.
“Ngokolwazi lwethu, esi sisifundo sokuqala sokusebenzisa i-tolcapone ukujonga isiphumo sokungabinamdla,” utshilo uKayser.
Uphononongo aluzange lwenzelwe ukuphanda izizathu eziye zanciphisa i-dopamine inxulunyaniswe nokungafuneki. Nangona kunjalo, ucacisile uKayser, izazinzulu zikholelwa ukuba ukungxamiseka kunxulunyaniswa nokungalingani kwi-dopamine phakathi kwe-cortex yangaphambili, elawula imisebenzi yesigqeba efana nolawulo lokuqonda kunye nokuzilawula, kunye ne-striatum, ekucingelwa ukuba ibandakanyeka kucwangciso kunye nohlengahlengiso. ukuziphatha okungaphezulu.
"Uninzi, ukuba alukho zonke, iziyobisi zokusetyenziswa kakubi, ezifana ne-cocaine kunye ne-amphetamine, zibandakanya ngokuthe ngqo okanye ngokungathanga ngqo inkqubo ye-dopamine, "utshilo uKayser. "Bathanda ukonyusa i-dopamine kwi-striatum, enokuthi ibuye ivuze isimilo esinganyanzelekanga. Ngendlela elula kakhulu, i-striatum ithi 'hamba,' kwaye i-cortex engaphambili ithi 'yima.' Ukuba usebenzisa i-cocaine, wongeza uphawu 'lokuhamba', kwaye uphawu 'lokuyeka' alunelanga ukulwa nalo. "
U-Kayser kunye neqela lakhe lophando baceba isifundo esilandelayo semiphumo ye-tolcapone ekuziphatheni kokusela. Nje ukuba sigqibe kwelokuba abasela bangakwazi na ukunyamezela eli yeza ngokukhuselekileyo, siza kubona ukuba linazo naziphi na iimpembelelo kwindlela abasela ngayo ngelixa belisela,” utshilo uKayser.
I-Tolcapone ivunyiwe njengeyeza le-Parkinson's disease, apho ukusilela okungapheliyo kwe-dopamine kuthintela ukunyakaza.
Ababhali bephepha kunye noDaicia C. Allen, BS, Ana Navarro-Cebrian, PhD, Jennifer M. Mitchell, PhD kunye nomlobi ophezulu uHoward L. Fields, MD, PhD, weGallo Centre kunye ne-UCSF.
Uphononongo luxhaswe ngemali evela kwi-Wheeler Centre ye-Neurobiology of Addiction, i-US Army Telemedicine kunye ne-Advanced Technology Research Centre, i-Alcoholic Beverage Medical Research Foundation / iSiseko soPhando loTywala kunye ne-State of California.
Isalathiso seJenali:
Andrew S. Kayser, uDaicia C. Allen, uAna Navarro-Cebrian, uJennifer M. Mitchell, kunye noHoward L. Fields. I-Dopamine, uQhagamshelwano lweCorticostriatal, kunye noKhetho lwe-Intertemporal. I-Journal ye-Neuroscience, i-4 kaJulayi 2012, i-32 (27): 9402-9409 DOI: 10.1523 / JNEUROSCI.1180-12.2012
ISIFUNDO
I-Dopamine, uqhagamshelwano lwe-corticostriatal, kunye nokukhetha phakathi kwexesha.
J Neurosci. 2012 Jul 4;32(27):9402-9.
Kayser AS, Allen DC, Navarro-Cebrian A, Mitchell JM, Fields HL.
imvelaphi
ISebe le-Neurology, iYunivesithi yaseCalifornia, eSan Francisco, eSan Francisco, eCalifornia 94143, iKliniki ye-Ernest Gallo kunye neZiko loPhando, i-Emeryville, i-California 94608, kunye neSebe le-Neurology, iMicimbi ye-Veterans ye-Northern California Health Care System, i-Martinez, i-California 94553.
Abstract
Izigqibo ezisekelwe kwixabiso zandisa iziphumo zokuziphatha. Ngenxa yokuba imivuzo elibazisiweyo ithotyiwe, utyekelo olwandisiweyo lokukhetha amabhaso amancinci, akhawulezileyo angakhokelela kukhetho oluncinci. Isaphulelo esiqatha sembuyekezo elibazisekileyo (ukungxama) kubonakalisa izifundo ezinomonakalo ongaphambili welobe kunye nokuphazamiseka kokuziphatha kubandakanya ukusetyenziswa gwenxa kweziyobisi. Ngokuhambelanayo, izifundo zezilwanyana kunye nobungqina obungathanga ngqo ebantwini bucebisa ukuba i-dopamine ephantsi kwi-cortex yangaphambili inegalelo kwisaphulelo esinyukayo ngokuphazamisa ukusebenza kwe-corticostriatal. Ukuvavanya le ngcamango ngokuthe ngqo, senze i-randomized, i-double-blind, i-counterbalanced, i-placebo-controlled controlled study apho silawula i-brain penetrant catechol-O-methyltransferase inhibitor tolcapone okanye i-placebo kwizifundo eziphilileyo ezenza umsebenzi wokulibaziseka. I-Tolcapone inyuse kakhulu ukhetho lokulibaziseka kwembuyekezo yemali, kwaye oku kunyuswa kwe-tolcapone-kuye kwahlanganiswa kunye nomsebenzi owandisiweyo we-BOLD kwi-putamen ye-ventral yasekhohlo kunye ne-insula yangaphambili. I-Tolcapone iphinde yatshintsha uxhulumaniso lwe-corticostriatal: ngokukodwa, ngokubangela ukuncipha kokubambisana phakathi kwe-ventral putamen kunye ne-pregenual cingulate cortex. Ezi ziphumo zibonisa ukuba ukunyusa amanqanaba e-cortical dopamine kunciphisa ukhetho olungenamtya ngokuguqula umsebenzi we-corticostriatal.
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