Summary
During chemical carcinogenesis by N-2-fluorenylacetamide, the hormonal status of female Sprague Dawley rats is largely modified. Thyroids present a modified activity which is evidenced by the histological study as well as T4 and T3 assays. In hypophysis, thyrotropic cells were found in an hyperactive state, a fact which is in agreement with the changes observed in thyroid follicles size and epithelial cells demonstrating an hyperactivity of thyroid glands. Despite this histological result, T4 serum level was lowered. T3 level was also decreased but to a lesser extent. We suggest that the low thyroid hormone level play a role in the relative protection of females versus males toward liver cancer induction by chemicals.
Zsammenfassung
Während der chemischen Leberkarzinogenese, hervorgerufen durch N-fluoren-2-acetamid, ist der Hormonhaushalt der weiblichen Sprague Dawley Ratten weitgehend verändert. Die Schilddrüse weist eine Aktivitätsveränderung auf, die durch die histologische Untersuchung sowie die T3-und T4-Analyse sichtbar wird. In der Hypophyse sind die thyreotropen Zellen in einem hyperaktivem Zustand, eine Tatsache, die mit der Beobachtung übereinstimmt, daß die Größe der Schilddrüsenfollikel und der epithelialen Zellen verändert ist, was eine Hyperaktivität der Schilddrüse beweist. Trotz der histologischen Veränderungen ist der T4-Spiegel im Serum erniedrigt. Auch der T3-Spiegel ist niedriger, jedoch nur geringfügig. Wir schließen daraus, daß die Erniedrigung des Spiegels der Schilddrüsenhormone eine Rolle beim relativen Schutz der weiblichen Ratten (im Gegensatz zu den männlichen) gegen Leberkrebs spielt, der durch Chemikalien hervorgerufen wurde.
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Stora, C., Aussel, C., Lafaurie, M. et al. Thyroid activity during hepatocarcinogenesis by N-2-fluorenylacetamide. J Cancer Res Clin Oncol 100, 41–50 (1981). https://doi.org/10.1007/BF00405900
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DOI: https://doi.org/10.1007/BF00405900