Rillema J A, Tarrant T M, Linebaugh B E
Department of Physiology, Wayne State University School of Medicine, Detroit, MI 48201.
Biochim Biophys Acta. 1989 Oct 30;1014(1):78-82. doi: 10.1016/0167-4889(89)90243-7.
Specific aspects of the prolactin stimulation of RNA, DNA and protein synthesis in the Nb2 node lymphoma cell line were determined. In time sequence studies the onset of the prolactin stimulation of the incorporation of radiolabeled precursors into these macromolecules was found to be 0.5-1 h for [3H]uridine incorporation into RNA, 1-2 h for [3H]leucine incorporation into protein, and 4-8 h for [3H]thymidine incorporation into DNA. The total DNA content of the cell cultures was increased by 12-18 hours after addition of prolactin. Amiloride, an inhibitor of the plasma-membrane-bound Na+/H+ antiporter, was found to inhibit the mitogenic effects of prolactin. Amiloride was also found to inhibit the prolactin stimulation of DNA, RNA and protein synthesis, thus suggesting that the initial regulation of the Na+/H+ antiporter may initiate these responses as well as the mitogenic effect of prolactin. In contrast, H-7, a drug which inhibits protein kinase C, had no effect on the magnitude of the prolactin stimulation of DNA, RNA or protein synthesis at a drug concentration (100 muM) that abolished the mitogenic effect of prolactin. The early effects of prolactin on RNA, DNA and protein synthesis would therefore appear not to involve an activation of protein kinase C.
我们确定了催乳素对Nb2结节淋巴瘤细胞系中RNA、DNA和蛋白质合成的刺激作用的具体方面。在时间序列研究中，发现催乳素刺激放射性标记前体掺入这些大分子的起始时间为：[3H]尿苷掺入RNA为0.5 - 1小时，[3H]亮氨酸掺入蛋白质为1 - 2小时，[3H]胸腺嘧啶核苷掺入DNA为4 - 8小时。添加催乳素后12 - 18小时，细胞培养物的总DNA含量增加。氨氯地平是一种质膜结合的Na+/H+反向转运蛋白抑制剂，被发现可抑制催乳素的促有丝分裂作用。还发现氨氯地平可抑制催乳素对DNA、RNA和蛋白质合成的刺激作用，因此表明Na+/H+反向转运蛋白的初始调节可能启动这些反应以及催乳素的促有丝分裂作用。相比之下，H - 7是一种抑制蛋白激酶C的药物，在药物浓度（100 μM）消除催乳素的促有丝分裂作用时，对催乳素刺激DNA、RNA或蛋白质合成的幅度没有影响。因此，催乳素对RNA、DNA和蛋白质合成的早期作用似乎不涉及蛋白激酶C的激活。
