RESUMEN
AIM:To investigate the effects of osteogenic induction media and the medias containing different concentration of calcium on the induction of osteogenic differentiation of human renal fibroblasts in vitro.METHODS: Culturedhuman renal fibroblasts were divided into 5 groups in this experiment: osteogenic induction group (osteogenic inductionmedia), CaⅠgroup (0.5 mmol/L Ca2 + media), CaⅡgroup (1.5 mmol/L Ca2 + media), Ca Ⅲ group (2.5 mmol/LCa2 + media) and control group (PBS).The cell activity in each groups was measured by MTT assay .At 9th day, the cellcalcium Alizarin red S staining and alkaline phosphatase (ALP) Gomori calcium cobalt staining were performed respectivelyto observe the formation of calcium nidus and the expression of ALP .In addition, the expression of Runt-related transcriptionfactor 2 (Runx2) at mRNA and protein levels was determined by real -time PCR and Western blot, respectively.RE- SULTS: The remarkable positive signs which represented the formation of calcium nidus and the deposit of calcium objectsin all experiment groups were observed .The mRNA and protein expression of Runx2 in osteogenic induction group increasedin accordance with the induction time .Compared with control group, the mRNA and protein expression of Runx2 inthe CaⅠ ~Ⅲ groups increased gradually in a calcium concentration dependent manner at the 9th induction day.CON- CLUSION: Human renal interstitial fibroblasts show the potential activity in osteogenic differentiation induced by osteogen -ic induction media or high level calcium in vitro, which may be account for the cytological formation of the Randall ’splaque in the kidney.