Forskolin对成骨样细胞蛋白激酶C及三磷酸肌醇的影响

Ｆｏｒｓｋｏｌｉｎ（ＦＳＫ）是一种植物二萜类化合物，为腺苷酸环化酶的特异激活剂，实验发现：ＦＳＫ和作为参照的诱导分化剂维甲酸（ＲＡ）单独或联合应用均可升高胞浆蛋白激酶Ｃ（ＰＫＣ）活性，并降低膜ＰＫＣ活性，ＦＳＫ可使表皮生长因子（ＥＧＦ）诱导的细胞内三磷酸肌醇（ＩＰ３－１，４，５）水平降低至对照组的４４．４％至６７％；ＦＳＫ与ＲＡ合用可显著降低成骨样细胞特征蛋白碱性磷酸酶（ＡＫＰ）的活性。以上结果表明，ＦＳＫ对成骨样细胞内磷脂酰肌醇信息传递体系有深刻影响，可能与其调节细胞的增殖分化有关。

Effect of Forskolin on PKC and IP_3 in UMR106 Cells

The effects of forskolin(FSK) on cytosolic and membrane protein kinase C(PKC) activity,inosine triphosphate-1,4,5(IP,-1,4,5) level and alkaline phosphatase(AKP) activity in rat osteoblastlike cells UMR106 were investigated.The results showed that,FSK and Retinoic acid(RA),an inducer of cell differentiation,increased cytosolic PKC activities by 32.8 folds and 3.9 folds respectively as compared with the control,but FSK RA increased cytosolic PKC activity 14.6 folds;Howerver,FSK,RA and FSK RA decreased membrane activities 53.9%,2.1% and 12.7% respectively;FSK reduced EGF-stimulated IP3 level by 44.4% and 67%;FSK RA decreased AKP activity by 57% as compared with the control.The results in this study demonstrated that FSK can deeply influence inositol phospholipid message transduction system,it may be related to modulation of cell proliferation and differentiation.