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\u0130nsan beynini c\u0259mi bir ne\u00e7\u0259 d\u0259r\u0259c\u0259 soyutmaq kifay\u0259tdir ki, neyronlar q\u0131sa m\u00fcdd\u0259td\u0259 f\u0259aliyy\u0259tini itirm\u0259y\u0259 ba\u015flas\u0131n. Oksigen s\u0259viyy\u0259si h\u0259tta bir-iki d\u0259qiq\u0259 kifay\u0259t q\u0259d\u0259r a\u015fa\u011f\u0131 d\u00fc\u015fs\u0259, h\u00fcceyr\u0259l\u0259r \u00f6l\u00fcr. B\u0259d\u0259n temperaturu donma n\u00f6qt\u0259sin\u0259 endikd\u0259 is\u0259 beyind\u0259 elektrik f\u0259aliyy\u0259ti tamamil\u0259 dayan\u0131r. Bununla bel\u0259, Arktika torpaq d\u0259l\u0259si (Urocitellus parryii) h\u0259r q\u0131\u015f q\u0259sd\u0259n beyninin temperaturunun 0\u00b0C-d\u0259n a\u015fa\u011f\u0131 d\u00fc\u015fm\u0259sin\u0259 imkan verir.<\/p>\n
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O, beyin\u0259 ged\u0259n qan ax\u0131n\u0131n\u0131 minimuma endirir v\u0259 h\u0259ft\u0259l\u0259rl\u0259 bu v\u0259ziyy\u0259td\u0259 qal\u0131r. Yaz g\u0259l\u0259nd\u0259 is\u0259 sanki he\u00e7 n\u0259 olmay\u0131bm\u0131\u015f kimi oyan\u0131r: yadda\u015f\u0131 qorunub saxlan\u0131r, beynind\u0259 is\u0259 he\u00e7 bir a\u015fkarlanan z\u0259d\u0259l\u0259nm\u0259 olmur, Forbes yaz\u0131r. Bu m\u0259m\u0259li planetd\u0259 \u0259n ekstremal q\u0131\u015f yuxusu strategiyalar\u0131ndan birini formala\u015fd\u0131r\u0131b: beynin geri d\u00f6n\u0259n \u015f\u0259kild\u0259 \u201cs\u00f6nd\u00fcr\u00fclm\u0259si\u201d.<\/p>\n
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Arktik torpaq d\u0259l\u0259sinin ekstremal q\u0131\u015f strategiyas\u0131<\/p>\n
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Arktik torpaq d\u0259l\u0259l\u0259ri Alyaska v\u0259 \u015eimali Kanadada ya\u015fay\u0131r; burada q\u0131\u015f s\u0259kkiz aya q\u0259d\u0259r uzana, hava temperaturu is\u0259 tez-tez \u221230\u00b0C-d\u0259n a\u015fa\u011f\u0131 d\u00fc\u015f\u0259 bil\u0259r. Yax\u015f\u0131 izolyasiya olunmu\u015f yuvalarda q\u0131\u015f yuxusuna ged\u0259n bir \u00e7ox heyvandan f\u0259rqli olaraq, bu d\u0259l\u0259l\u0259r donmu\u015f torpa\u011f\u0131n t\u0259sirin\u0259 daha \u00e7ox m\u0259ruz qal\u0131rlar.<\/p>\n
American Journal of Physiology jurnal\u0131nda t\u0259svir edildiyi kimi, q\u0131\u015f yuxusu zaman\u0131 onlar\u0131n b\u0259d\u0259n temperaturu \u22122,9\u00b0C-y\u0259 q\u0259d\u0259r en\u0259 bilir ki, bu da bu g\u00fcn\u0259 q\u0259d\u0259r m\u0259m\u0259lil\u0259rd\u0259 qeyd\u0259 al\u0131nm\u0131\u015f \u0259n a\u015fa\u011f\u0131 g\u00f6st\u0259ricidir. Bundan az sonra \u00fcr\u0259k d\u00f6y\u00fcnt\u00fcs\u00fc d\u0259qiq\u0259d\u0259 t\u0259xmin\u0259n 200 vuru\u015fdan 10-dan a\u015fa\u011f\u0131 d\u00fc\u015f\u00fcr. N\u0259f\u0259salma dem\u0259k olar ki, dayan\u0131r, beyin f\u0259aliyy\u0259ti is\u0259 g\u00fccl\u0259 sezilir. Buna baxmayaraq, m\u00f6c\u00fcz\u0259vi \u015f\u0259kild\u0259 beyin \u00f6lm\u00fcr.<\/p>\n
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H\u00fcceyr\u0259 s\u0259viyy\u0259sind\u0259 d\u0259l\u0259nin beyni \u201ctorpor\u201d (donuq hal) adlanan v\u0259ziyy\u0259t\u0259 ke\u00e7ir v\u0259 bu zaman:<\/p>\n
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neyronlar\u0131n f\u0259aliyy\u0259ti k\u00fctl\u0259vi \u015f\u0259kild\u0259 azal\u0131r (impulsla\u015fma z\u0259ifl\u0259yir);<\/p>\n
sinaptik \u00f6t\u00fcr\u00fclm\u0259 yat\u0131r\u0131l\u0131r;<\/p>\n
enerji s\u0259rfiyyat\u0131 normal s\u0259viyy\u0259nin 5%-ind\u0259n d\u0259 a\u015fa\u011f\u0131 d\u00fc\u015f\u00fcr.<\/p>\n
Vacib m\u0259qam odur ki, neyronlar\u0131n bu f\u0259aliyy\u0259tsizliyi t\u0259sad\u00fcfi deyil. Torpor fazas\u0131 d\u0259l\u0259y\u0259 ion kanallar\u0131n\u0131n aktivliyini bo\u011fma\u011fa, qlutamat\u0131n ifraz\u0131n\u0131 azaltma\u011fa v\u0259 h\u00fcceyr\u0259 membranlar\u0131n\u0131 sabitl\u0259\u015fdirm\u0259y\u0259 imkan verir. N\u0259tic\u0259d\u0259, ad\u0259t\u0259n insanlarda oksigen \u00e7at\u0131\u015fmazl\u0131\u011f\u0131 v\u0259 ya h\u0259ddind\u0259n art\u0131q soyuma zaman\u0131 neyronlar\u0131 m\u0259hv ed\u0259n eksaytotoksiklik prosesi tamamil\u0259 qar\u015f\u0131s\u0131 al\u0131n\u0131r. Sad\u0259 des\u0259k, arktik torpaq d\u0259l\u0259si beynini \u201cenerjiy\u0259 q\u0259na\u0259t rejimi\u201dn\u0259 ke\u00e7irir.<\/p>\n
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D\u0259l\u0259 oksigensiz nec\u0259 sa\u011f qal\u0131r?<\/p>\n
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Arktik torpaq d\u0259l\u0259sinin q\u0131\u015f yuxusunun \u0259n heyr\u0259tamiz x\u00fcsusiyy\u0259tl\u0259rind\u0259n biri beyninin i\u015femiyaya (qan v\u0259 oksigen \u00e7at\u0131\u015fmazl\u0131\u011f\u0131na) nec\u0259 d\u00f6z\u00fcml\u00fc olmas\u0131d\u0131r. Stroke jurnal\u0131nda 2006-c\u0131 ild\u0259 d\u0259rc olunmu\u015f t\u0259dqiqata g\u00f6r\u0259, insanda h\u0259tta q\u0131sam\u00fcdd\u0259tli i\u015femiya bel\u0259 kalsiumun h\u00fcceyr\u0259l\u0259r\u0259 ax\u0131n\u0131na, mitoxondril\u0259rin s\u0131radan \u00e7\u0131xmas\u0131na v\u0259 h\u00fcceyr\u0259 \u00f6l\u00fcm\u00fcn\u0259 s\u0259b\u0259b ola bil\u0259r. Lakin t\u0259\u0259cc\u00fcbl\u00fcd\u00fcr ki, arktik torpaq d\u0259l\u0259sinin neyronlar\u0131 bu da\u011f\u0131d\u0131c\u0131 z\u0259ncirvari proses\u0259 m\u00fcqavim\u0259t g\u00f6st\u0259r\u0259 bilir.<\/p>\n
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Ara\u015fd\u0131rmada qeyd olunur ki, torpor zaman\u0131 onlar\u0131n beyin h\u00fcceyr\u0259l\u0259ri mitoxondril\u0259rin b\u00fct\u00f6vl\u00fcy\u00fcn\u00fc qoruyur v\u0259 oksidl\u0259\u015fdirici stresd\u0259n yay\u0131n\u0131r. Z\u0259r\u0259rli s\u0259rb\u0259st radikallar\u0131 bo\u011fan metabolik reaksiyalar\u0131 kataliz ed\u0259n antioksidant mexanizml\u0259r aktivl\u0259\u015fir. Sad\u0259 dill\u0259 des\u0259k, bu qabiliyy\u0259ti qabaqlay\u0131c\u0131 h\u00fcceyr\u0259 \u201cm\u00fch\u0259ndisliyi\u201d il\u0259 m\u00fcqayis\u0259 etm\u0259k olar.<\/p>\n
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B\u0259lk\u0259 d\u0259 \u0259n qeyri-adi k\u0259\u015ff sinapslarla ba\u011fl\u0131d\u0131r. D\u0259rin torpor zaman\u0131 d\u0259l\u0259nin beynind\u0259 sinaptik \u0259laq\u0259l\u0259r qism\u0259n \u201cs\u00f6k\u00fcl\u00fcr\u201d: dendrit tikanlar\u0131 geri \u00e7\u0259kilir v\u0259 neyronlararas\u0131 \u0259laq\u0259 k\u0259skin azal\u0131r.<\/p>\n
\u018fks\u0259r heyvanlar \u00fc\u00e7\u00fcn bu, tibbi f\u0259lak\u0259t olard\u0131, \u00e7\u00fcnki sinapslar\u0131n itirilm\u0259si neyrodegenerativ x\u0259st\u0259likl\u0259r v\u0259 idrak qabiliyy\u0259tl\u0259rinin z\u0259ifl\u0259m\u0259si il\u0259 s\u0131x ba\u011fl\u0131d\u0131r. Lakin arktik torpaq d\u0259l\u0259si \u00fc\u00e7\u00fcn bu, geri d\u00f6n\u0259n prosesdir: o, q\u0131sa oyanma fazalar\u0131 zaman\u0131 vaxta\u015f\u0131r\u0131 isin\u0259r\u0259k sinapslar\u0131 s\u00fcr\u0259tl\u0259 b\u0259rpa edir. Bu da o dem\u0259kdir ki, yazda yuvas\u0131ndan \u00e7\u0131xanad\u0259k heyvan\u0131n neyron arxitekturas\u0131 funksional bax\u0131mdan normal olur.<\/p>\n
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Donmadan yaranan z\u0259d\u0259l\u0259rd\u0259n nec\u0259 yay\u0131n\u0131rlar<\/p>\n
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M\u0259m\u0259lil\u0259rd\u0259 q\u0131\u015f yuxusu fasil\u0259siz proses deyil v\u0259 arktik torpaq d\u0259l\u0259si d\u0259 istisna deyil. O, bir ne\u00e7\u0259 h\u0259ft\u0259d\u0259n bir q\u0131sa m\u00fcdd\u0259t\u0259 (bir sutkadan az) normal b\u0259d\u0259n temperaturuna q\u0259d\u0259r isinib oyan\u0131r. Bu oyanmalar energetik bax\u0131mdan \u00e7ox \u201cbahal\u0131d\u0131r\u201d: q\u0131\u015f boyu s\u0259rf olunan enerjinin b\u00f6y\u00fck hiss\u0259si m\u0259hz buna gedir.<\/p>\n
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B\u0259s bu q\u0259d\u0259r baha ba\u015fa g\u0259lirs\u0259, niy\u0259 \u00fcmumiyy\u0259tl\u0259 bu d\u00f6vri isinm\u0259l\u0259r laz\u0131md\u0131r? Journal of Comparative Physiology jurnal\u0131nda 2009-cu ild\u0259 d\u0259rc olunan ara\u015fd\u0131rmaya g\u00f6r\u0259, bu, beynin \u201ctexniki xidm\u0259ti\u201d \u00fc\u00e7\u00fcn vacibdir. \u0130sinm\u0259 DNT-nin b\u0259rpas\u0131na, z\u00fclallar\u0131n funksiyalar\u0131n\u0131n yenid\u0259n i\u015f\u0259 d\u00fc\u015fm\u0259sin\u0259 v\u0259 neyromediator sisteml\u0259rinin tarazlanmas\u0131na imkan verir. Torpor z\u0259d\u0259l\u0259nm\u0259l\u0259ri sanki pauzaya al\u0131r, d\u00f6vri oyanmalar is\u0259 y\u0131\u011f\u0131l\u0131b qalm\u0131\u015f x\u0131rda \u201cnasazl\u0131qlar\u0131\u201d aradan qald\u0131rma\u011fa k\u00f6m\u0259k edir.<\/p>\n
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\u018fks\u0259r dig\u0259r heyvanlarda b\u0259d\u0259n temperaturunun 0\u00b0C-d\u0259n a\u015fa\u011f\u0131 d\u00fc\u015fm\u0259si h\u00fcceyr\u0259l\u0259ri c\u0131ran buz kristallar\u0131n\u0131n \u0259m\u0259l\u0259 g\u0259lm\u0259sin\u0259 s\u0259b\u0259b olard\u0131. Science jurnal\u0131nda d\u0259rc olunmu\u015f pioner t\u0259dqiqat g\u00f6st\u0259rir ki, arktik torpaq d\u0259l\u0259l\u0259ri bunu iki mexanizm vasit\u0259sil\u0259 \u00f6nl\u0259yir: mayel\u0259rin supersoyudulmas\u0131 (donmadan a\u015fa\u011f\u0131 temperaturda maye qalmas\u0131) v\u0259 periferik toxumalarda buzun n\u0259zar\u0259tli \u015f\u0259kild\u0259 formala\u015fd\u0131r\u0131lmas\u0131.<\/p>\n
Maraql\u0131d\u0131r ki, bu mexanizm beyind\u0259 buzun \u0259m\u0259l\u0259 g\u0259lm\u0259sini tamamil\u0259 qar\u015f\u0131s\u0131n\u0131 al\u0131r. X\u00fcsusi z\u00fclallar, membranlar\u0131n d\u0259yi\u015fmi\u015f t\u0259rkibi v\u0259 h\u00fcceyr\u0259d\u0259nk\u0259nar mayenin kimyas\u0131na d\u0259qiq n\u0259zar\u0259t neyronlar\u0131 0\u00b0C-d\u0259n a\u015fa\u011f\u0131 temperaturda bel\u0259 maye v\u0259ziyy\u0259td\u0259 saxlay\u0131r. Qeyd ed\u0259k ki, bu s\u0259viyy\u0259d\u0259 n\u0259zar\u0259t m\u0259m\u0259lil\u0259r aras\u0131nda son d\u0259r\u0259c\u0259 nadirdir v\u0259 daha \u00e7ox \u015faxtaya davaml\u0131 amfibiya v\u0259 s\u00fcr\u00fcn\u0259nl\u0259rd\u0259 m\u00fc\u015fahid\u0259 olunan strategiyalara b\u0259nz\u0259yir.<\/p>\n
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Bu niy\u0259 yaln\u0131z d\u0259l\u0259l\u0259r \u00fc\u00e7\u00fcn deyil, bizim \u00fc\u00e7\u00fcn d\u0259 vacibdir<\/p>\n
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Arktik torpaq d\u0259l\u0259l\u0259ri neyroproteksiya \u00fczr\u0259 t\u0259dqiqatlarda model obyekt\u0259 \u00e7evrilib. Onlar\u0131n beyninin hipotermiya v\u0259 i\u015femiyaya nec\u0259 d\u00f6zd\u00fcy\u00fcn\u00fc anlamaq art\u0131q insultun, \u00fcr\u0259yin dayanmas\u0131n\u0131n v\u0259 k\u0259ll\u0259-beyin travmalar\u0131n\u0131n m\u00fcalic\u0259si \u00fc\u00e7\u00fcn yeni metodlar\u0131n i\u015fl\u0259nib haz\u0131rlanmas\u0131na t\u0259sir g\u00f6st\u0259rib. \u0130nsanlar\u0131 torpora b\u0259nz\u0259r v\u0259ziyy\u0259t\u0259 salmaq ideyas\u0131 x\u00fcsus\u0259n t\u0259cili tibbd\u0259 v\u0259 uzunm\u00fcdd\u0259tli kosmik u\u00e7u\u015flar kontekstind\u0259 aktiv t\u0259dqiqat m\u00f6vzusudur.<\/p>\n
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D\u0259l\u0259 g\u00f6st\u0259rir ki, m\u0259m\u0259lil\u0259rin beyni d\u00fc\u015f\u00fcnd\u00fcy\u00fcm\u00fcz q\u0259d\u0259r k\u00f6vr\u0259k deyil. Do\u011fru molekulyar \u015f\u0259raitd\u0259 o, \u0259vv\u0259ll\u0259r qeyri-m\u00fcmk\u00fcn hesab etdiyimiz ekstremal y\u00fckl\u0259nm\u0259l\u0259r\u0259 tab g\u0259tir\u0259 bilir.<\/p>\n
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Bu qabiliyy\u0259t t\u0259sad\u00fcf\u0259n yaranmay\u0131b: arktik torpaq d\u0259l\u0259l\u0259ri s\u0259rt seleksiya t\u0259zyiqi alt\u0131nda t\u0259kam\u00fcl ke\u00e7irib v\u0259 q\u0131\u015f\u0131 sa\u011f \u00e7\u0131xara bilm\u0259m\u0259k n\u0259sli k\u0259silm\u0259 dem\u0259k idi. Onlar soyuqdan qa\u00e7maq \u0259v\u0259zin\u0259, ona \u0259n d\u0259rin bioloji s\u0259viyy\u0259d\u0259 uy\u011funla\u015f\u0131blar. N\u0259tic\u0259d\u0259 beyin geri d\u00f6n\u0259n \u015f\u0259kild\u0259 \u201cs\u00f6nd\u00fcr\u00fcl\u0259 bil\u0259n\u201d \u00e7evik bir sistem\u0259 \u00e7evrilib.<\/p>\n
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T\u0259kam\u00fcl biologiyas\u0131 bax\u0131m\u0131ndan bu, biz\u0259 xat\u0131rlad\u0131r: intellekt v\u0259 sa\u011f qalma h\u0259r zaman fasil\u0259siz neyron f\u0259aliyy\u0259ti t\u0259l\u0259b etmir. B\u0259z\u0259n \u0259n a\u011f\u0131ll\u0131 strategiya \u2013 n\u0259 vaxt tam istirah\u0259t rejimin\u0259 ke\u00e7m\u0259k laz\u0131m oldu\u011funu bilm\u0259kdir.<\/p>\n
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<\/p>\n","protected":false},"excerpt":{"rendered":"
\u0130nsan beynini c\u0259mi bir ne\u00e7\u0259 d\u0259r\u0259c\u0259 soyutmaq kifay\u0259tdir ki, neyronlar q\u0131sa m\u00fcdd\u0259td\u0259 f\u0259aliyy\u0259tini itirm\u0259y\u0259 ba\u015flas\u0131n. Oksigen s\u0259viyy\u0259si h\u0259tta bir-iki d\u0259qiq\u0259 kifay\u0259t q\u0259d\u0259r a\u015fa\u011f\u0131 d\u00fc\u015fs\u0259, h\u00fcceyr\u0259l\u0259r \u00f6l\u00fcr. B\u0259d\u0259n temperaturu donma n\u00f6qt\u0259sin\u0259 endikd\u0259 is\u0259 beyind\u0259 elektrik f\u0259aliyy\u0259ti tamamil\u0259 dayan\u0131r. Bununla bel\u0259, Arktika torpaq d\u0259l\u0259si (Urocitellus parryii) h\u0259r q\u0131\u015f q\u0259sd\u0259n beyninin temperaturunun 0\u00b0C-d\u0259n a\u015fa\u011f\u0131 d\u00fc\u015fm\u0259sin\u0259 imkan verir. […]<\/p>\n","protected":false},"author":1,"featured_media":68,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-65","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-dunya"],"_links":{"self":[{"href":"https:\/\/idealxeber.az\/index.php?rest_route=\/wp\/v2\/posts\/65","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/idealxeber.az\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/idealxeber.az\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/idealxeber.az\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/idealxeber.az\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=65"}],"version-history":[{"count":0,"href":"https:\/\/idealxeber.az\/index.php?rest_route=\/wp\/v2\/posts\/65\/revisions"}],"wp:attachment":[{"href":"https:\/\/idealxeber.az\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=65"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/idealxeber.az\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=65"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/idealxeber.az\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=65"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}