IGF对大鼠平滑肌细胞骨桥蛋白表达的影响

目的　研究胰岛素样生长因子 (IGF)对培养的大鼠胸主动脉平滑肌细胞骨桥蛋白表达的影响。方法　大鼠平滑肌细胞被随机分为对照组 ,IGF I不同浓度 (5、10、2 0、3 0μg·L-1)及时间 (3、2 4、48h)干预组 ,用RT PCR及Western blotting技术结合光密度扫描分析 ,观察IGF I对培养的大鼠胸主动脉平滑肌细胞内骨桥蛋白基因表达的影响。结果　IGF I 2 0 μg·L-1即能刺激平滑肌细胞内骨桥蛋白的表达 ,RT PCR结果分析骨桥蛋白与 β actinmRNA比值 3h干预组 1 0 2 9± 0 0 60 ,2 4h干预组 1 0 3 2± 0 0 71和 48h干预组1 13 2± 0 190分别较对照组提高了 3 9 70 % ,40 44 %和5 4 0 5 % ;Western blotting分析 3h干预组骨桥蛋白量 19 5 1± 16 983 ,2 4h后 167 98± 15 780和 48h后 175 64±9 913分别较对照组提高 5 3 3 0 %、1 15倍和 1 2 5倍。结论　说明IGF I能在基因水平上刺激大鼠平滑肌细胞内骨桥蛋白的表达

Effects of insulin-like growth factor on expression of osteopontin in rat vascular smooth muscle cells

AIM To explore whether or not the function of insulin like growth factor (IGF I) in promoting osteopontin gene expression and protein synthesis of rat vascular smooth muscle cell (VSMC). METHODS Cultured cells were incubated with different concentration of IGF I for different hours, then RT PCR and Western blotting analysis were used to observed the effects of IGF I on osteopontin expression of rat vascular smooth muscle cells RESULTS IGF I (20 μg·L -1 ) could obviously induce the gene expression and protein synthesis of osteopontin, RT PCR results showed that the ratio of mRNA of osteopontin and β actin in cells incubated with IGF I (20 μg·L -1 ) for 3, 24 and 48 h increased by 39 70%,40 44% and 54 05% respectively, as compared with that of the control ( P< 0 05), and Western blotting analysis also showed that protein synthesis of osteopontin in cells incubated with IGF I for 3, 24 and 48 h increased by 53 30%,1 15 times and 1 25 times respectively, as compared with that of the control ( P< 0 05) CONCLUSION IGF I could stimulate osteopontin gene expression and protein synthesis of rat vascular smooth muscle cells