Effect of sex hormones of developmental of thymus tumor in spontaneous thymona BUF / Mna rats, with special reference to sex hormone receptors and thymulin (FTS)
| Autor: | Issei Kawaschima, Akira Akatsuka, Mayumi Nakano, Rei Urano, Hideko Fujii-Hanamoto, Kou Sakabe, Kanji Seiki |
|---|---|
| Rok vydání: | 1994 |
| Předmět: |
medicine.medical_specialty
Thymoma biology medicine.drug_class Sex hormone receptor Androgen medicine.disease Pathology and Forensic Medicine Thymulin chemistry.chemical_compound Endocrinology Sex hormone-binding globulin chemistry Estrogen Physiology (medical) Internal medicine medicine biology.protein Receptor Hormone |
| Zdroj: | Pathophysiology. 1:117-125 |
| ISSN: | 0928-4680 |
| DOI: | 10.1016/0928-4680(94)90026-4 |
| Popis: | Using spontaneous thymoma Buffalo / Mna (BUF / Mna) rats, the influence of sex hormones (SH) in the development of Thymoma was examined, with special reference to the localization of the cells containing SH receptors (SHR), thymulin (FTS) or SHR-mRNA. The results were as follows: (i) prepubertal ovariectomy strong induced thymogenesis, which was almost completely inhibited by estrogen (E) compensation, whereas neither orchidectomy nor androgen (A) compensation affected tumor growth; (ii) in addition, neither prepubertal castration nor SH administration in both sexes induced a change in the general structure of thymoma apart from reduced tissue size; (iii) the SHR level in both sexes decreased with age after the onset of thymoma (i.e., 9 months of age). Meanwhile, neither prepubertal orchidectomy nor A compensation affected the A receptor (AR) level, whereas ovariectomy decreased the E receptor (ER) level, which was completed restored by E; (iv) the FTS level decreased with age after the onset of thymoma. Meanwhile, Prepubertal orchidectomy increased the FTS level, which was restored by A, whereas ovariectomy decreased it, an effect which was further enhance by E; (v) SHR-positive epithelial cells (ECs) were localized in subcapsular and enlarged corticol areas, whereas FTS-positive cells were mainly localized in tumor cell cluster, which were SHR-negative; and (vi) SHR-mRNA was expressed in large polygonal cells that were similar to SHR-positive cells. SHR-mRNA was also expressed in Hassalls' corpuscle. These clearly demonstrate that E actully inhibits or retards thymomagenesis, where A may have no direct relation to tumor growth, and suggest that E mediates tumor growth by its receptors in ECs, where so, at least partly, through conversion to E. The present results may also suggest that, once thymomagenesis is set up, tumor cells lose their sensitivity to SH, resulting in Automatic differentriation and/ or proliferation according to the process programmed by the dominant gene Tsr-1 . |
| Databáze: | OpenAIRE |
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