REGULATORY EFFECTS OF INSULIN-LIKE GROWTH FACTOR-I AND FACTOR-II ON BONE-COLLAGEN SYNTHESIS IN RAT CALVARIAL CULTURES
REGULATORY EFFECTS OF INSULIN-LIKE GROWTH FACTOR-I AND FACTOR-II ON BONE-COLLAGEN SYNTHESIS IN RAT CALVARIAL CULTURES
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DOI：
10.1210/endo-124-1-301
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发表时间：
1989-01-01
期刊：
影响因子：
4.8
通讯作者：
CANALIS, E
中科院分区：
文献类型：
--
作者：
MCCARTHY, TL;CENTRELLA, M;CANALIS, E
胰岛素样生长因子I和II （IGF-I和-II）是由骨骼细胞分泌的多肽，被认为是骨形成的调节剂。研究了IGF-I和-II对完整胎鼠颅骨培养物中胶原合成和降解的影响，以及对胎鼠顶骨中富成骨细胞（Ob）中I型胶原转录水平的影响。IGF-I和-II增加了[3H]脯氨酸并入I型胶原蛋白，而不依赖于它们对细胞复制的影响。IGF-I和-II也能降低颅骨培养物中的胶原降解。尽管IGF-I在10 nM时刺激胶原合成，而IGF-II在30 nM时刺激胶原合成，但这两种因子的作用相似。在Ob细胞中，IGF-I和-II也增加了[3H]脯氨酸在I型胶原中的掺入，但在100 nM下观察到效果，两种因子都没有减少胶原降解。使用大鼠I型胶原cDNA探针对IGF-I和igf - ii处理的细胞进行槽印迹分析，发现I型胶原转录物增加。综上所述，IGF-I和-II增加了完整颅骨培养中骨胶原的合成，减少了胶原的降解；对胶原合成的影响与Ob细胞中转录物水平的增加有关。
Insulin-like growth factors I and II (IGF-I and -II) are polypeptides secreted by skeletal cells and are considered regulators of bone formation. IGF-I and -II were studied for their effects on collagen synthesis and degradation in cultures of intact fetal rat calvariae and on type I collagen transcript levels in osteoblast-enriched (Ob) cells from fetal rat parietal bone. IGF-I and -II increased [3H]proline incorporation into type I collagen independently of their effect on cell replication. IGF-I and -II also decreased collagen degradation in calvarial cultures. Both factors had similar actions, although IGF-I stimulated collagen synthesis at 10 nM, and IGF-II at 30 nM. In Ob cells, IGF-I and -II also increased [3H]proline incorporation into type I collagen, but the effect was seen at 100 nM, and neither factor decreased collagen degradation. Slot blot analysis of IGF-I- and IGF-II-treated cells, using a rat type I collagen cDNA probe, revealed an increase in type I collagen transcripts. In conclusion, IGF-I and -II increase bone collagen synthesis and decrease collagen degradation in cultures of intact calvariae; the effect on collagen synthesis correlates with an increase in transcript levels in Ob cells.