Ndemanga: Nora Volkow ndiye mutu wa NIDA. Izi zikukhudza ntchito ya dopamine (D2) receptors ndi deensitization mu mowa.
Volkow Ikhoza Kuvumbulutsidwa Yankho la Kuledzera
Psychiatric News June 4, 2004
Vuto la 39 Namba 11 Page 32
Jim Rosack
Matenda osokoneza bongo atha kukhala "kusintha kwa mamilimita amisili" momwe zoyeserera sizimadziwika kuti ndizofunikira, komabe zovuta zakugwiritsa ntchito mankhwala osokoneza bongo mu ubongo wa dopamine ndizofunika kwambiri, wamkulu wa NIDA amakhulupirira.
Nora Volkow, MD, waphunzira momwe ubongo wamunthu umayankhira pazinthu zosokoneza bongo kwa zaka pafupifupi 25. Tsopano, atatha zaka zonse zowunika ndi kafukufuku wazachipatala, akugwiritsa ntchito udindo wake monga director of the National Institute on Drug Abuse (NIDA) kuti apeze yankho la funso lofunika kwambiri: chifukwa chiyani ubongo wamunthu umakhala osokoneza bongo?
Inde, patadutsa zaka makumi anayi kudza makumi asanu ndi limodzi ndikuganizira funso losavuta, Volkow-akugwiritsa ntchito kafukufuku wake ndi ena a ochita kafukufuku-tsopano akukhulupirira kuti munda uli njira yopita ku yankho.
Motsogozedwa ndi iye, ofufuza olipidwa ndi NIDA akufuna yankho. Mwezi watha, Volkow adagawana malingaliro ake ndi khamu lodzasefukira pamsonkhano wopambana wazamisala pamsonkhano wapachaka wa APA ku New York City.
Kafukufuku wambiri awonetsa kuti mankhwala onse osokoneza bongo amachulukitsa zochitika za dopamine mu limbic system yaubongo wamunthu. Koma, Volkow adanenetsa, "ngakhale kuti kuwonjezeka kwa dopamine ndikofunikira kuti munthu akhale ndi chizolowezi chomangokhalira kusuta, sikuti kumafotokozera za kuledzera. Ngati mupatsa aliyense nkhanza, milingo yawo ya dopamine imakulanso. Komabe ambiri samangokhalira kusuta. ”
Kwa zaka 10 zapitazi, kafukufuku wa ubongo wasonyeza kuti kuwonjezereka kwa dopamine komwe kumagwiritsidwa ntchito ndi mankhwala osokoneza bongo ndikochepa kwa iwo omwe ali oledzera kusiyana ndi omwe sakuledzera. Komabe kwa iwo omwe ali pachiopsezo chotere, kuwonjezeka kwakukulu kochepa mu dopamine kumabweretsa chilakolako chofunafuna mowa mwauchidakwa mobwerezabwereza.
Kodi dopamine ikugwira nawo ntchitoyi? ” Volkow anafunsa. “Nchiyani chimayambitsa kukakamizidwa kumwa mankhwala osokoneza bongo? Kodi n'chiyani chimachititsa kuti munthuyo asiye kudziletsa? ”
Kujambula Kumadzala Mabokosi Ena
Kupita patsogolo kwa luso la kulingalira kwa ubongo kwapangitsa ofufuza kugwiritsa ntchito zida zosiyanasiyana zamagetsi kuti ayang'ane zomwe zimapangidwa mu dongosolo la dopamine-wotumiza wa dopamine ndi ma dopamine receptors (osachepera magawo anayi osiyanasiyana a dopamine receptors adadziwika mpaka pano). Kuphatikiza apo, ofufuza tsopano atha kuwona kusintha kwa kagayidwe kake ka ubongo pakapita nthawi, pogwiritsa ntchito makina am'magazi a shuga, kuti awone momwe mankhwala osokoneza bongo amakhudzira kagayidwe kameneka.
Kupita patsogolo kumeneku kwatipangitsa kuti tiwone mankhwala osiyanasiyana ozunza komanso zomwe zimachitika ndikusintha [mu dongosolo la dopamine] komwe kumalumikizidwa ndi iliyonse ya izi, "Volkow adalongosola. "Zomwe tikuyenera kudziwa ndi zomwe zimachitika ndikusintha komwe kumafala pamankhwala onse ozunza."
”Zinawonekera molawirira kwambiri kuti mankhwala ena ozunguza bongo amawoneka kuti akukhudza wonyamula wa dopamine, koma ena sanatero. Kafufuzidwe kenaka kanayang'ana pa zolandilira za dopamine ndi metabolism kuti mupeze zovuta, Volkow adalongosola. Chimodzi mwazomwe adaphunzira mu 1980s chidawonetsa kuchepa kosasunthika kwa dopamine receptor concentration, makamaka mu ventral striatum, ya odwala omwe amamwa mankhwala osokoneza bongo a cocaine, poyerekeza ndi owongolera. Volkow anachita chidwi atazindikira kuti kuchepa kumeneku kumakhala kwanthawi yayitali, kupatula lingaliro loti atuluke mu cocaine.
"Kuchepetsa kwa dopamine mtundu-2 receptors sikutanthauza kuti munthu azikhala ndi cocaine yekha," Volkow adapitiliza. Kafukufuku wina adapeza zotsatira zofananira kwa odwala omwe amamwa mowa, heroin, ndi methamphetamine.
"Ndiye, kodi zikutanthauzanji, kuchepetsa kuchepa kwa ma D2 receptors atamwa mowa?" Volkow anafunsa.
Kukonzanso Meta Yoyenera
"Nthawi zonse ndimayambira ndi mayankho osavuta, ndipo ngati sakugwira ntchito, ndiye kuti ndimalola kuti ubongo wanga usokonezeke," anatero Volkow, zomwe zidakometsa khamulo.
Dopamine system, iye anati, amachitapo kanthu zosayenera-chinachake chomwe chingakhale chosangalatsa, chofunika, kapena chofunika kumvetsera. Zinthu zina zingakhale zovuta, monga zolemba kapena zosayembekezereka kapena zovuta zowopsya pamene zikuwopseza m'chilengedwe.
"Chifukwa chake dopamine ikunenadi kuti," Onani, samalani izi-ndikofunikira, "adatero Volkow. "Dopamine imasonyeza kulimba mtima."
Koma, adapitiliza kuti, dopamine nthawi zambiri imakhala mkati mwa synapse kwa kanthawi kochepa-kochepera ma microseconds a 50-isanabwezeretsedwe ndi wotumiza wa dopamine. Chifukwa chake munthawi zonse, ma dopamine receptors ayenera kukhala ochulukirapo komanso osamala ngati ati awonetse kuphulika kwakanthawi kwa dopamine komwe cholinga chake ndikunyamula uthenga, "Tcherani khutu!"
Pomwe kuchepa kwa D2 kulandira mankhwala ozunguza bongo, munthu ali ndi chichepere chochepetseratu kuti asamangokhalira kuchita zachiwerewere.
Volkow adati: "Mankhwala osokoneza bongo ambiri, amaletsa wotumiza wa dopamine m'mabwalo a mphotho yaubongo, kulola kuti ma neurotransmitter akhalebe m'mphepete mwa nthawi yayitali. Izi zimabweretsa mphotho yayikulu komanso yokhalitsa, ngakhale munthuyo wachepetsa zolandila.
"Popita nthawi, omwe amamwa mankhwala osokoneza bongo amaphunzira kuti zoyeserera zachilengedwe sizikhala zopanda ntchito," Volkow adatsimikiza. "Koma mankhwala osokoneza bongo ndiwo."
Chifukwa chake, adafunsa, "Tidziwa bwanji kuti nkhuku ndi dzira liti?" Kodi kupitiriza kugwiritsa ntchito mankhwala osokoneza bongo kumabweretsa kuchepa kwa ma D2 receptors, kapena kodi kuchuluka kwa olandila kumabweretsa chizolowezi?
Kafukufuku tsopano akuyankha funsoli, Volkow anatsimikizira. Ndipo zikuwoneka kuti zotsirizazo zingakhale yankho. Kwa anthu osadziwika amene sanadziwe kuti akugwiritsa ntchito mankhwala osokoneza bongo, pali mitundu yosiyanasiyana ya D2 receptor concentrations. Zina zowonongeka mwachibadwa zimakhala ndi ma D2 omwe ali ochepa ngati maphunziro ena a cocaine.
Mufukufuku wina, Volkow adati, ofufuza adapatsa mankhwala osokoneza bongo mthupi mwawo ndipo adawafunsa kuti awonetsetse kuti mankhwalawa amawapangitsa bwanji kumva.
"Omwe ali ndi milingo yayikulu ya olandila D2 adati ndizowopsa, ndipo iwo omwe ali ndi magawo ochepa a zolandila a D2 amatha kunena kuti zimawapangitsa kukhala osangalala," adatero Volkow.
"Tsopano," adapitiliza, "sizitanthauza kuti anthu omwe ali ndi mulingo wochepa wa olandila D2 ali pachiwopsezo chokhala osokoneza bongo. Koma zitha kutanthauza kuti anthu omwe ali ndi ma D2 receptors ambiri amatha kukhala ndi chidwi chambiri pakukula kwakukulu kwa dopamine yomwe imagwiritsidwa ntchito ndi mankhwala osokoneza bongo. Chidziwitsochi chimakhala chobisira, chomwe chitha kuwateteza ku chizolowezi chomwa mankhwalawa. ”
Akuti, ngati ofufuza zamankhwala osokoneza bongo atha kupeza njira yowonjezeretsa zolandilira za D2 muubongo, "mutha kusintha anthu omwe ali ndi milingo yotsika ya D2 ndikupanga machitidwe obwezera poyankha mankhwala osokoneza bongo."
Zotsatira zaposachedwa kuchokera kwa m'modzi mwa omwe adachita kafukufuku pambuyo pa a Volkow adawonetsa kuti ndizotheka mbewa kuti zilowetse mu adenovirus muubongo wopanga D2 receptor, ndikupangitsa kuchuluka kwa D2 receptor. Poyankha, mbewa zimachepetsanso kumwa kwawo mowa. Ofufuza ena posachedwapa adafotokozanso zomwe apezazo ndi cocaine.
"Koma," Volkow anachenjeza, "mukufunikira zoposa kungotsika pang'ono kwa ma D2 receptors." Kuyerekeza maphunziro a kagayidwe ka shuga kwawonetsa kuti metabolism imachepa kwambiri mu orbital frontal cortex (OFC) ndikuwonetsa gyrus (CG) poyankha cocaine, mowa, methamphetamine, ndi chamba mwa omwe ali osokoneza bongo, poyerekeza ndi owongolera. Ndipo, adaonjezeranso, kuchepa kwa kagayidwe kamayendedwe kamakhudzana kwambiri ndi kuchepa kwa ma D2 receptors.
Volkow adanenanso kuti kulephera kugwira ntchito ku OFC ndi CG "kumapangitsa kuti anthu alephera kuweruza kuthekera kwa mankhwalawo - amamwa mankhwalawo mopitirira muyeso, komabe sawasangalatsa ndipo, nthawi zambiri, amakhala ndi zotsatirapo zoyipa. ” Komabe, sangathe kusiya kugwiritsa ntchito mankhwalawa.
Kafukufuku wina akuwonetsa kuti kuchepetsa kuteteza; mphotho, zolimbikitsa, ndi kuyendetsa galimoto; komanso maphunziro ndi maulendo okumbukira onse ali osalongosoka kwa anthu omwe ali ndi matenda osokoneza bongo, adatero. Chotsatira chake, chithandizo cha chizolowezi chofuna kumwa mowa chimafuna kuyanjana, njira zoyenera.
"Palibe amene amasankha kuti akhale osokoneza bongo," adamaliza Volkow. "Mwachidziwikire, sangathe kusankha kuti asakhale osokoneza bongo."
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