{"id":94450,"date":"2026-01-27T12:31:06","date_gmt":"2026-01-27T12:31:06","guid":{"rendered":"https:\/\/www.europesays.com\/ee\/94450\/"},"modified":"2026-01-27T12:31:06","modified_gmt":"2026-01-27T12:31:06","slug":"talveks-aju-kahandav-nariline-voib-aidata-moista-ajuhaiguste-tekkepohjuseid-loodus","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/ee\/94450\/","title":{"rendered":"Talveks aju kahandav n\u00e4riline v\u00f5ib aidata m\u00f5ista ajuhaiguste tekkep\u00f5hjuseid | Loodus"},"content":{"rendered":"<p>Mets-karihiired (Sorex araneus) suudavad oma ajumahtu vastu talve 30 protsendi v\u00f5rra kahandada ning selle hiljem uuesti tagasi kasvatada, selgus v\u00e4rskest uuringust.<\/p>\n<p>Teadlased on n\u00fc\u00fcd v\u00e4lja selgitanud selle haruldase kohastumuse evolutsioonilise p\u00e4ritolu ning geenid, mis seda t\u00f5en\u00e4oliselt v\u00f5imaldavad. Peale selle, et n\u00e4htus on iseenesest t\u00e4helepanuv\u00e4\u00e4rne, v\u00f5ib see avada ka uusi v\u00f5imalusi inimese aju taandarenguga seotud haiguste uurimisel ja ravis.<\/p>\n<p>Ebatavaline kohastumus on tuntud Dehneli fenomenina, mis sai oma nime Poola zooloogi August Dehneli j\u00e4rgi, kes kirjeldas esimesena mets-karihiirte v\u00f5imet aju hooajaliselt kahandada. Kohastumus aitab talvel energiat s\u00e4\u00e4sta ja toidunappusega toime tulla<\/p>\n<p>Dehneli fenomen on k\u00fcll haruldane, kuid omaju suurust v\u00e4hendavad peale mets-karihiirte hooajaliselt ka veel Euroopa mutid (Talpa europaea), v\u00e4ikenugised (Mustela nivalis) ja k\u00e4rbid (Mustela erminea). Neil k\u00f5igil on kiire ainevahetus ja nad ei maga talveund. See v\u00f5ibki sundida neid toidupuuduse ajal energias\u00e4\u00e4stu nimel \u00e4\u00e4rmuslikke lahendusi kasutama.<\/p>\n<p>USA Stony Brooki \u00fclikooli \u00f6koloog William Thomas juhtis uuringut, milles kaardistati hariliku mets-karihiire kogu genoom. T\u00f6\u00f6r\u00fchm v\u00f5rdles seda teiste Dehneli fenomeni ilmutavate imetajate genoomidega, et selgitada v\u00e4lja, millised geneetilised mehhanismid on selle kohastumuse taga.<\/p>\n<p>Teadlased leidsid, et mitmel Dehneli fenomeniga liigil avaldusid tugevamalt geenid, mis on seotud ajurakkude tekkega. Mets-karihiire puhul paistis eriti silma geen VEGFA, mis on seotud vere-aju barj\u00e4\u00e4ri l\u00e4bilaskvusega ja v\u00f5ib muuta aju toitainete suhtes tundlikumaks. Samuti oli tema genoomis rohkem geene, mis on seotud DNA parandamise ja pikaealisusega.<\/p>\n<p>Aktiivsed olid ka veeregulatsiooniga seotud geenid. See toetab oletust, et n\u00e4rilised v\u00e4hendavad aju mahtu ajutiselt l\u00e4bi vee kaotuse, mitte ajurakkude arvu v\u00e4henemise arvelt.<\/p>\n<p>Mets-karihiir on levinud ka Eestis. Loomake meenutab esmapilgul hiirt, kuid erinevalt hiirtest on ta silmad v\u00e4ikesed, koon pikk, k\u00f5rvad v\u00e4ikesed ja karvastiku varjus.<\/p>\n<p>Uuring avaldati teadusajakirjas <a href=\"https:\/\/academic.oup.com\/mbe\/advance-article\/doi\/10.1093\/molbev\/msag006\/8419347?login=false\" target=\"_blank\" rel=\"noopener nofollow\">Molecular Biology and Evolution<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"Mets-karihiired (Sorex araneus) suudavad oma ajumahtu vastu talve 30 protsendi v\u00f5rra kahandada ning selle hiljem uuesti tagasi kasvatada,&hellip;\n","protected":false},"author":2,"featured_media":94451,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[12],"tags":[6601,45940,26,27,45939,37,33,35,34,36,31,32,21,28,29,45938,45937,19,25,23,24,22,20,30],"class_list":{"0":"post-94450","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-eesti","8":"tag-aju","9":"tag-august-dehnel","10":"tag-breaking-news","11":"tag-breakingnews","12":"tag-dehneli-fenomen","13":"tag-ee","14":"tag-eesti","15":"tag-eesti-keel","16":"tag-estonia","17":"tag-estonian","18":"tag-featured-news","19":"tag-featurednews","20":"tag-headlines","21":"tag-latest-news","22":"tag-latestnews","23":"tag-mets-karihiir","24":"tag-narilise","25":"tag-news","26":"tag-populaarseimad-lood","27":"tag-top-stories","28":"tag-topstories","29":"tag-uldised-uudised","30":"tag-uudised","31":"tag-viimased-uudised"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ee\/115967078133774064","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/posts\/94450","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/comments?post=94450"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/posts\/94450\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/media\/94451"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/media?parent=94450"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/categories?post=94450"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ee\/wp-json\/wp\/v2\/tags?post=94450"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}