模拟失重大鼠骨非胶原蛋白变化与骨矿盐再分布

Changes in Bone Noncollagenous Proteins and Bone Mineral Redistribution in Tail Suspended Rats

为了解悬吊模拟失重环境下骨非胶原蛋白变化对骨矿盐再分布的影响，观察了模拟失重２１天大鼠第６胸椎（Ｔ６）中骨ＢＧＰ、白蛋白、氨基多糖（ＧＡＧ）和矿盐含量变化，以及血甲状旁腺激素（ＰＴＨ）和降钙素（ＣＴ）含量的变化。结果显示，悬吊大鼠血ＣＴ浓度显著升高，ＰＴＨ浓度无变化。悬吊大鼠Ｔ６中ＧＡＧ、白蛋白和矿盐含量显著增加，但ＢＧＰ含量无明显改变。结果表明，悬吊模拟失重大鼠骨矿盐再分布与骨质中白蛋白含量增加有关。该结果不支持模拟失重大鼠骨矿盐再分布与成骨细胞活性增加有关的观点。

Abstract The purpose of the study was to clarify whether the noncollagenous proteins play a role in bone mineral redistribution during simulated weightlessness. Noncollagenous proteins,such as bone Gla protein(BGP)and albumin,have been shown to be effective in promoting bone mineralization. In this study ,the contents of BGP,albumin,glycosaminoglycan(GAG) and mineral in the sixth thoratic vertebra(T 6) were determined in rats suspended by the tail for 21 d.The concentration of blood parathyroid hormone(PTH) and calcitonin(CT) were also determined. The results showed that the concentration of CT was significantly increased, but PTH had no significant change in the suspended rats.The contents of GAG,albumin and mineral were significantly increased in T 6 of the suspended rats,but the BGP content had no significant change. The data indicate that the mineral redistribution is related to the increase in albumin of bone mass.These results do not support the idea that bone mineral redistribution during simulated weightlessness is resulted from the increase in osteoblastic activity. $$$$weightlessness simulation bone mineral redistribution albumins osteocalcin calcitonin parathyroid hormones