Zeytin F N, Rusk S F, Raymond V, Mandell A J
Laboratory for Neuroendocrinology, Salk Institute, La Jolla, California 92037.
Endocrinology. 1988 Mar;122(3):1121-8. doi: 10.1210/endo-122-3-1121.
A clonal cell line (44-2C) which synthesizes and secretes somatostatin, neurotensin, calcitonin (CT), and CT gene-related peptide and transiently expresses c-fos was used to characterize the mechanism of action of basic fibroblast growth factor (bFGF). bFGF had two modes of action: 1) short term incubation of 44-2C cells with bFGF increased the cellular content of neurotensin, somatostatin, and CT; and 2) bFGF enhanced the response of the cells to rat hypothalamic GRF-mediated cAMP efflux. The long term action of bFGF was manifested by the permissive effect of the molecule. bFGF had a sustained effect on RNA synthesis, and pretreatment with bFGF for 24 h altered the time course of response of the cells to rat GRF. In this cell line the cellular action of bFGF was not mediated via protein kinase-C action. bFGF was not mitogenic in 44-2C cells. bFGF stimulated uridine incorporation without affecting thymidine incorporation. Results obtained with actinomycin-D and alpha-amanitin suggest that the above effects of bFGF can be correlated with increased RNA stability produced by bFGF.
一种合成并分泌生长抑素、神经降压素、降钙素（CT）和CT基因相关肽且瞬时表达c-fos的克隆细胞系（44-2C）被用于表征碱性成纤维细胞生长因子（bFGF）的作用机制。bFGF有两种作用模式：1）用bFGF对44-2C细胞进行短期孵育会增加神经降压素、生长抑素和CT的细胞含量；2）bFGF增强了细胞对大鼠下丘脑生长激素释放因子（GRF）介导的cAMP外流的反应。bFGF的长期作用表现为该分子的允许作用。bFGF对RNA合成有持续影响，用bFGF预处理24小时会改变细胞对大鼠GRF反应的时间进程。在该细胞系中，bFGF的细胞作用不是通过蛋白激酶-C作用介导的。bFGF在44-2C细胞中不具有促有丝分裂作用。bFGF刺激尿苷掺入而不影响胸苷掺入。用放线菌素-D和α-鹅膏蕈碱获得的结果表明，bFGF的上述作用可能与bFGF产生的RNA稳定性增加有关。
