1α,25-二羟维生素D_3对大鼠成骨细胞增殖分化及周期的影响

Effect of 1α,25-dihydroxyvitamin D_3 on proliferation and cell cycle of osteoblasts in vitro

在SD大鼠成骨细胞(Osteoblast,OB)体外培养体系中添加不同浓度1α,25-二羟维生素D3(0、10-9、10-8、10-7mol/L),作用24、48、72 h,测定OB增殖率、碱性磷酸酶(ALP)活性,作用48 h流式细胞仪测定OB周期。结果显示,10-9mol/L1α,25-二羟维生素D3作用24、48、72 h均促进OB增殖(P<0.05或P<0.01),抑制ALP活性(P<0.01);10-8、10-7mol/L作用24、48 h,OB增殖率与对照组差异不显著(P>0.05),但24 h时ALP活性均明显升高(P<0.05或P<0.01),48 h则抑制了ALP活性并使OB滞留在G2/M期(P<0.05或P<0.01);72 h时10-7mol/L组OB增殖率极显著低于其余各组(P<0.01),并使ALP活性升高(P<0.01)。表明低浓度1α,25-二羟维生素D3能促进OB增殖,抑制其分化;高浓度1α,25-二羟维生素D3能抑制OB增殖,促进其分化,并使细胞滞留在G2/M期。

To study the influence of 1α, 25-dihydroxyvitamin D3 on proliferation and cell cycle of osteoblasts （OB） in vitro. OB were isolated from calvaria bone, then dealt with various concentration of 1α, 25-dihydroxyvitamin D3 （0,10^-9,10^-8, 10^-7 mol/L）. After 24,48 and 72 h cultivation, the proliferation and the activity of alkali phosphatase（ALP） of OB was observed. 48 h incubation later,the changes of cell phase was analyzed using flow cytometer. Compared with the control group, 10^-9 mol/L 1α, 25-dihydroxyvitamin D3 promoted proliferation of OB in vitro （P〈0.05） ,and inhibited the ALP activity （P〈0.01）. The group with 10^-8 , 10^-7 mol/L 1α, 25-dihydroxyvitamin D3 had lower proliferation rate of OB than that of 10^-9 mol/L 1α,25-dihydroxyvitamin D3（P〈0.05 or P〈0.01）, but inhibited the ALP activity （P〈0.05 or P〈0.01） at 24 h. At 72 h,10^-7 mol/L 1α,25-dihydroxyvitamin D3 had the lowest proliferation rate of OB,and the highest ALP activity （P〈0.01）. 10^-8 , 10^-7 mol/L 1α,25-dihydroxyvitamin D3 caused G2/M arrest （P〈0.05 or P〈0.01）. Low dosage of 1α,25-dihydroxyvitamin D3 can promote proliferation and inhibit differentiation,while higher dosage of 1α, 25-dihydroxyvitamin D3 can inhibit proliferation, promote differentiation and cause G2/M arrest.