Malendowicz L K, Nussdorfer G G, Markowska A, Nowak K W
Department of Histology and Embryology, School of Medicine, University of Poznan, Poland.
Cytobios. 1992;71(286-287):191-9.
Adult female rats were treated for 4 or 6 days consecutively with dexamethasone (Dx; 100 micrograms kg-1 day-1) alone or with ACTH (100 micrograms kg-1 day-1) for 2, 4 or 6 days. After 2 days of ACTH administration, zona fasciculata cells increased in volume, and the blood concentration of corticosterone was raised. Basal corticosterone secretion by adrenal slices appeared to be enhanced by ACTH treatment only when calculating per adrenal pair (and not per unit wt of adrenals). A significant increase in the number of metaphase cells was observed after only 4 days of ACTH administration. It is suggested that (1) the first action of ACTH on Dx-suppressed rats is to induce the hypertrophy of adrenocortical cells; (2) the steroidogenic capacity of adrenocortical cells is directly proportional to their average volume; and (3) the stimulatory effect of ACTH on the proliferative activity of adrenocortical cells is subsequent to the stimulation of their specialized functions.
成年雌性大鼠连续4天或6天单独接受地塞米松（Dx；100微克/千克/天）治疗，或连续2天、4天或6天接受促肾上腺皮质激素（ACTH；100微克/千克/天）治疗。给予促肾上腺皮质激素2天后，束状带细胞体积增大，皮质酮的血浓度升高。仅在按每对肾上腺计算（而非按肾上腺单位重量计算）时，促肾上腺皮质激素处理似乎增强了肾上腺切片的基础皮质酮分泌。仅给予促肾上腺皮质激素4天后，就观察到中期细胞数量显著增加。有人提出：（1）促肾上腺皮质激素对用Dx抑制的大鼠的首要作用是诱导肾上腺皮质细胞肥大；（2）肾上腺皮质细胞的类固醇生成能力与其平均体积成正比；（3）促肾上腺皮质激素对肾上腺皮质细胞增殖活性的刺激作用是在刺激其特殊功能之后出现的。
