Objective        To determine the effect of domestic porous tantalum on the cell adhesion

proliferation and mRNA expression of osteogenetic genes in rat osteoblasts.       Methods       The osteoblasts of neonatal SD rats were isolated and identified. The fluid extract from porous tantalum was made according to the national standards of China. Then MTT assay was used to assess the growth and proliferation of osteoblasts in the fluid extract. Inverted phase contras

t microscopy and scanning electron microscopy were used to observe the attachment and growth of osteoblasts on the porous tantalum. The mRNA expression levels of osteopontin (OPN)

osteocalcin (OC)

and fibronectin (FN) were detected in the osteoblasts treated with or without the 5 days’ treatment of the fluid extract by RT-qPCR.       Results        Gross observation found that our porous tantalum presented the porous structure of 3-dimensional stereoscopic configuration. Scanning electron microscopy showed that the interconnected pores

in a size ranging from 400-600 μm

were distributed uniformly in the cross-section and surface of the porous tantalum. MTT assay showed that the osteoblasts grew well and proliferated rapidly in the fluid extract of porous tantalum

and there was no significant difference between the cells with or without the extract treatment (

P

>0.05). Scanning electron microscopy showed that the osteoblasts seeded onto the porous tantalum attached successfully to the “metal trabeculae” and penetrated into the tantalum pores. In the later stage

osteoblasts excreted bone matrix to overlay the surface of porous tantalum. In addition

the mRNA expression levels of OPN

OC and FN were increased by 1.45

1.79

and 1.69 times

respectively.       Conclusion      The domestic porous tantalum possesses good 3-dimensional stereoscopic configuration and excellent biocompatibility

and stimulates the adhesion and proliferation and enhances the expression of osteogenic genes in osteoblasts.