Inoue K, Hattori M, Sakai T, Inukai S, Fujimoto N, Ito A
Department of Morphology, Gunma University, Maebashi, Japan.
Endocrinology. 1990 May;126(5):2313-20. doi: 10.1210/endo-126-5-2313.
Four kinds of cultured clonal cell line were established from estrogen-induced mammotropic pituitary tumor. These clones showed differences of hormone secretion, morphology, and response to estrogen. One clone tentatively designated MtT/E, consisted of spindle-shaped epithelial cells and showed the strongest adhesion to the culture dish, but did not secrete any pituitary hormone. The second cell line, designated MtT/S, secreted only GH, showed very weak contact with the culture dish, and proliferated almost anchorage independently. the MtT/S cells were mainly spherical and formed floating or weakly adherent clusters. Some of them had very long dendrite- or neurite-like cell processes. Electron microscopic examination of the MtT/S cells showed a normal somatotrope-like appearance, i.e. the presence in the cytoplasm of many GH-containing secretory granules, well developed rough endoplasmic reticulum, and Golgi apparatus. Furthermore, these cells secreted GH in response to stimulation with GRF. The third cell line with an ovoid cell appearance tentatively designated MtT/SM, secreted both PRL and GH, and showed anchorage-dependent proliferation. The fourth cell line designated MtT/Se secreted only a small amount of GH. Among these newly established cell lines, MtT/Se was the smallest in size and showed estrogen-dependent proliferation. The many small secretory-like granules present in the cytoplasm of MtT/Se cells showed no immunocytochemically positive reaction for anterior pituitary hormone. MtT/S and MtT/SM cell lines were also sensitive to estrogen.
从雌激素诱导的促乳腺垂体瘤中建立了四种培养的克隆细胞系。这些克隆在激素分泌、形态以及对雌激素的反应方面存在差异。一个暂定为MtT/E的克隆由纺锤形上皮细胞组成，对培养皿的黏附力最强，但不分泌任何垂体激素。第二个细胞系，命名为MtT/S，仅分泌生长激素（GH），与培养皿的接触非常弱，几乎不依赖贴壁增殖。MtT/S细胞主要呈球形，形成漂浮或弱贴壁的细胞团。其中一些细胞具有非常长的树突状或神经突状细胞突起。对MtT/S细胞的电子显微镜检查显示出正常的促生长激素细胞样外观，即细胞质中存在许多含生长激素的分泌颗粒、发达的粗面内质网和高尔基体。此外，这些细胞在生长激素释放因子（GRF）刺激下分泌生长激素。第三个细胞系细胞呈卵圆形，暂定为MtT/SM，分泌催乳素（PRL）和生长激素，且依赖贴壁增殖。第四个细胞系命名为MtT/Se，仅分泌少量生长激素。在这些新建立的细胞系中，MtT/Se体积最小，且显示出雌激素依赖性增殖。MtT/Se细胞细胞质中存在的许多小分泌样颗粒对垂体前叶激素无免疫细胞化学阳性反应。MtT/S和MtT/SM细胞系也对雌激素敏感。
