β-GP influences on rat osteoblast development at the early period of culture i.e , the non-mineralization phase, and changes with the different cell passages were investigated. Alkaline phosphatase (ALP) was chosen a...β-GP influences on rat osteoblast development at the early period of culture i.e , the non-mineralization phase, and changes with the different cell passages were investigated. Alkaline phosphatase (ALP) was chosen as a main object. Northern blot analysis revealed up to two-fold increase in the steady statelevel of ALP mRNA after stimulation of rat osteoblast with 10 mM β-GP- Likewise, 10 mM β-GP induced a 10─30 % increase in ALP activity (P< 0. 01) of early passages (1 to 4), but not of later passages (5 to 6). The β-GP induced increase in ALP activity was totally inhibited by the protein synthesis inhibitor, cycloheximide (50 μM).β- GP stimulation was found to be without effect on cell proliferation measured as 3H-thymidine incorporation. It is concluded that β-GP has no effect on proliferation but induces an increase in both mRNA level and activity of ALP in the non-mineralization phase of cultures of fetal rat calvarial cells , which lasts for several passages but will disappear in older cultures.展开更多
The regulation of cellular differentiation by progesterone in fetal rat calvarial osteoblasts was investigated. Our results showed that cells cultured in the presence of progesterone had a 7% increase in the alkaline ...The regulation of cellular differentiation by progesterone in fetal rat calvarial osteoblasts was investigated. Our results showed that cells cultured in the presence of progesterone had a 7% increase in the alkaline phosphatase activity when compared to untreated cells. The concentration of osteocalcin in the conditioned medium from progesterone treated osteoblasts was 28% higher than that of untreated controls. In addition,administration of progesterone significantly enhanced the number and area of bone nodules. In conclusion, progesterone stimulates the differentiation of fetal rat calvarial osteoblastic cells in vitro展开更多
文摘β-GP influences on rat osteoblast development at the early period of culture i.e , the non-mineralization phase, and changes with the different cell passages were investigated. Alkaline phosphatase (ALP) was chosen as a main object. Northern blot analysis revealed up to two-fold increase in the steady statelevel of ALP mRNA after stimulation of rat osteoblast with 10 mM β-GP- Likewise, 10 mM β-GP induced a 10─30 % increase in ALP activity (P< 0. 01) of early passages (1 to 4), but not of later passages (5 to 6). The β-GP induced increase in ALP activity was totally inhibited by the protein synthesis inhibitor, cycloheximide (50 μM).β- GP stimulation was found to be without effect on cell proliferation measured as 3H-thymidine incorporation. It is concluded that β-GP has no effect on proliferation but induces an increase in both mRNA level and activity of ALP in the non-mineralization phase of cultures of fetal rat calvarial cells , which lasts for several passages but will disappear in older cultures.
文摘The regulation of cellular differentiation by progesterone in fetal rat calvarial osteoblasts was investigated. Our results showed that cells cultured in the presence of progesterone had a 7% increase in the alkaline phosphatase activity when compared to untreated cells. The concentration of osteocalcin in the conditioned medium from progesterone treated osteoblasts was 28% higher than that of untreated controls. In addition,administration of progesterone significantly enhanced the number and area of bone nodules. In conclusion, progesterone stimulates the differentiation of fetal rat calvarial osteoblastic cells in vitro