小鼠Calbindin-D28k基因对钙代谢的影响

目的：探讨Calbindin-D28k对钙代谢的影响及作用。方法：制备维生素D受体（VDR）／Calbindin-D28k双基因剔除小鼠模型，常规及高钙饮食下，检测小鼠体重、摄食量、血尿参数值及甲状旁腺大小等。结果：常规饮食下，双基因剔除小鼠发育更迟缓，体重比VDR单基因剔除小鼠轻42％。尿钙的分泌更高，并发展为严重的继发性甲状旁腺功能亢进。高钙饮食下，VDR及双基因剔除小鼠的血钙离子水平恢复正常。结论：CaBP-D28k对钙代谢平衡起了重要的作用，它的作用大都被CaBP-D9k代偿。

Effect of mice calbindin-D28k gene on calcium metabolism

Objective To investigate the effect of mice calbindin(CaBP) D28k gene on calcium metabolism.Methods Body weight,diet intake,calcium level of serum and urinary as well as parathyroid size of mice were determined and analyzed on Vitamin D Receptor(VDR)/CaBP-D28k double knockout(KO) mice which were given regular or high Ca-Lac diet.Results The growth of double KO mice were more retarded and smaller in body weight than VDR KO mice on regular diet.The double KO mice had higher urinary calcium excretion and developed more severe secondary hyperparathyroidism than VDR KO mice.The blood ionized calcium levels were normal in VDR and the double KO mice on the high Ca-Lac diet.Conclusion These results suggest that CaBP-D28k plays a critical role in maintaining calcium homeostasis and its effect can be compensated mostly by CaBP-D9k.