Kiss Z, Chung T
Hormel Institute, University of Minnesota, Austin 55912, USA.
Biochem Biophys Res Commun. 1996 Jan 17;218(2):505-9. doi: 10.1006/bbrc.1996.0090.
Treatments of serum-starved NIH 3T3 fibroblasts with either 100 nM phorbol-12-myristate 13-acetate (PMA) or 1 mM choline phosphate (ChoP) greatly enhanced, in a mutually inhibitory manner, the stimulatory effect of insulin on DNA synthesis. Wortmannin and GF 109203X, inhibitors of phosphatidylinositol 3'-kinase and protein kinase C, respectively, inhibited only the combined mitogenic effects of PMA and insulin, but not that of ChoP and insulin. In the presence of 0.5% fetal calf serum, both ChoP and insulin, but not PMA, retained their mitogenic activities, while PMA abolished the stimulatory effect of insulin on DNA synthesis. The results indicate that PMA can both enhance and inhibit the mitogenic action of insulin, depending on the presence of serum factors and ChoP.
用100 nM佛波醇-12-肉豆蔻酸酯13-乙酸酯（PMA）或1 mM胆碱磷酸酯（ChoP）处理血清饥饿的NIH 3T3成纤维细胞，以相互抑制的方式极大地增强了胰岛素对DNA合成的刺激作用。渥曼青霉素和GF 109203X分别是磷脂酰肌醇3'-激酶和蛋白激酶C的抑制剂，它们仅抑制PMA和胰岛素的联合促有丝分裂作用，而不抑制ChoP和胰岛素的联合促有丝分裂作用。在存在0.5%胎牛血清的情况下，ChoP和胰岛素都保留了它们的促有丝分裂活性，而PMA则没有，同时PMA消除了胰岛素对DNA合成的刺激作用。结果表明，根据血清因子和ChoP的存在情况，PMA既能增强也能抑制胰岛素的促有丝分裂作用。
