Nichols N R, Tracy K E, Funder J W
J Steroid Biochem. 1984 Nov;21(5):487-96. doi: 10.1016/0022-4731(84)90321-2.
To analyze direct effects of steroids on the rates of synthesis (and/or degradation) of newly synthesized proteins of the rat heart, we have used high resolution two-dimensional gel electrophoresis and autoradiography. A collective steroid domain of nineteen proteins, comprising fifteen with an increased rate of synthesis and four with a decreased rate of synthesis, was consistently seen in cultures of cardiac muscle and non-muscle cells from neonatal rats following 24 h incubation with 10(-7) dexamethasone. Similarly, incubation with 10(-7) M sex steroids, mineralocorticoids, and other glucocorticoids including the highly selective compound RU26988, established the glucocorticoid-specificity of the response. Different subsets of this glucocorticoid domain were seen for collagenase- or trypsin-dispersed primary cultures of cardiac muscle and non-muscle cells or for passaged cultures of cardiac non-muscle cells. Six polypeptides were consistently induced in all cardiac cultures, regardless of cell morphology. Two polypeptides were consistently induced only in those cultures containing cardiac non-muscle cells, whereas protein l, of identical Mr(approximately 52K) and pI (approximately 5.3) to desmin, was induced only in cultures of spontaneously contractile cardiac muscle cells. The glucocorticoid domain proteins described herein represent direct steroid effects on cardiac cells and are therefore candidate mediators of physiological glucocorticoid effects on, for example, differentiation and contractility.
为了分析类固醇对大鼠心脏新合成蛋白质合成率（和/或降解率）的直接影响，我们使用了高分辨率二维凝胶电泳和放射自显影技术。在用10⁻⁷地塞米松孵育24小时后，在新生大鼠的心肌细胞和非肌肉细胞培养物中，始终观察到一个由19种蛋白质组成的类固醇共同作用域，其中15种蛋白质的合成率增加，4种蛋白质的合成率降低。同样，用10⁻⁷M的性激素、盐皮质激素和其他糖皮质激素（包括高度选择性化合物RU26988）孵育，确定了反应的糖皮质激素特异性。对于胶原酶或胰蛋白酶分散的心肌细胞和非肌肉细胞原代培养物或心脏非肌肉细胞传代培养物，观察到了这个糖皮质激素作用域的不同亚组。无论细胞形态如何，在所有心脏培养物中始终诱导出6种多肽。仅在含有心脏非肌肉细胞的培养物中始终诱导出2种多肽，而与结蛋白Mr（约52K）和pI（约5.3）相同的蛋白质1仅在自发收缩的心肌细胞培养物中被诱导。本文所述的糖皮质激素作用域蛋白质代表了类固醇对心脏细胞的直接作用，因此是生理性糖皮质激素对例如分化和收缩性等作用的候选介质。
