Málková J, Michalová K, Pribyl T, Schreiber V
Neoplasma. 1977;24(3):277-84.
Pituitary weight, mitotic index and chromosomes were studied in male rats following a single or repeated dose of estradiol-benzoate for a total period of 210 days. Estrogen-induced pituitary hyperplasy eventually resulted in large pituitary tumors in some animals. The mitotic index increased until day 90, when it diminished, with chromosomes partly replaced by chromatin clusters. Most of the cells of the hyperplastic pituitaries maintained a normal diploid karyotype. However, a limited number of abnormal stem-lines with marker chromosomes appeared at a relatively early stage of the hyperplastic reaction of the pituitary. Later the tumors were characterized by an increase of number of aneuploid cells. In the bone marrow estrogens significantly lowered the mitotic index without any detectable change in chromosomal morphology.
对雄性大鼠单次或重复注射苯甲酸雌二醇，持续210天，研究其垂体重量、有丝分裂指数和染色体情况。雌激素诱导的垂体增生最终在一些动物中导致大的垂体肿瘤。有丝分裂指数在第90天前增加，之后下降，此时染色体部分被染色质团簇取代。增生垂体的大多数细胞维持正常的二倍体核型。然而，在垂体增生反应的相对早期阶段出现了少数带有标记染色体的异常细胞系。后来肿瘤的特征是非整倍体细胞数量增加。在骨髓中，雌激素显著降低有丝分裂指数，而染色体形态没有任何可检测到的变化。
