Dokument

Summary:
Ziel dieser Doktorarbeit war es die Bedeutung des braunen Fettgewebes, über seine anerkannte Funktion hinaus, in Säugetieren zu charakterisieren. Besonders die Rolle von aktivem UCP1 während des Aufwachvorgangs auf dem Torpor und in der Prävention von reaktiven Sauerstoffradikalen während der zitterfreien Wärmebildung standen im Fokus dieser Arbeit. Um den evolutionären Ursprung von UCP1 und braunem Fett besser zu verstehen, wurden Studien an zwei Vertretern der phylogenetisch ursprünglichen Überordnung Afrotheria durchgeführt. Anhand dieser Ergebnisse sollte ein neues Licht auf die Evolution des braunen Fettgewebes geworfen werden. War wirklich die Migration in kältere, holarktische Regionen der Hauptgrund seiner Entstehung? Die vorliegende Arbeit ist in vier Kapitel gegliedert, deren Inhalt im Folgenden zusammengefasst wird.

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