Dauça M, Hourdry J
Cell Tissue Res. 1979 Dec;204(2):279-91. doi: 10.1007/BF00234639.
The conjoined effects of thyroxine and X-rays on the intestinal wall were studied using Alytes obstetricans tadpoles in premetamorphosis. Thyroxine alone induces degeneration of the larval epithelium (primary epithelium) and its replacement by a secondary epithelium. The latter is derived from stem cells via the development of islets. In animals submitted to irradiation only, many of these stem cells showed signs of necrosis. In irradiated larvae treated with thyroxine, the secondary epitheliocytes were rare and never formed islets. Radioautographic observations confirmed their very low proliferation rate. Contrary to what was observed in the hormone treated larvae, cell fragments of the primary epithelium were extruded in the connective tissue, and phagocytes appear to infiltrate the epithelium. In animals treated with thyroxine and later submitted to irradiation, islets of secondary epitheliocytes developed while some cells degenerated. There again, the phagocytes were noted in both the connective tissue and the epithelium.
利用产婆蟾（Alytes obstetricans）变态前的蝌蚪，研究了甲状腺素和X射线对肠壁的联合作用。单独使用甲状腺素会诱导幼虫上皮（原代上皮）退化，并被次生上皮取代。次生上皮通过胰岛的发育从干细胞衍生而来。在仅接受辐照的动物中，许多这些干细胞显示出坏死迹象。在用甲状腺素处理的辐照幼虫中，次生上皮细胞很少见，且从未形成胰岛。放射自显影观察证实了它们极低的增殖率。与在激素处理的幼虫中观察到的情况相反，原代上皮的细胞碎片被挤出到结缔组织中，并且吞噬细胞似乎浸润上皮。在用甲状腺素处理并随后接受辐照的动物中，次生上皮细胞的胰岛发育，同时一些细胞退化。同样，在结缔组织和上皮中都发现了吞噬细胞。
