RESUMEN
Objective:To observe the effect of serum of kidney Yang deficiency rats on the expression of β-catenin，osteoprotegerin(OPG) and nuclear transcription factor-κB receptor activator ligand (RANKL) in the co-culture system and regulatory of icariin on it， and to explore the possible mechanism of inducing osteoporosis.Method:The 16 male SD rats were randomly divided into blank group and model group， 8 rats in each group. 10 mL·kg-1 adenine was administrated to stomach to establish kidney yang deficiency model. Serum was separated and extracted after the model was established successfully. Isolation and culture of osteoblast（OB） and osteoclast（OC） in vitro， OB was observed and identified by alkaline phosphatase（ALP），alizarin red and Giemsa staining， OC was identified by tartrate resistant acid phosphatase（TRAP） staining， OB-OC co-culture system was established in transwell cell， icariin group（100 μmol·L-1）， blank group， icariin（100 μmol·L-1） + serum group， serum group and Dickkopf1（DKK-1） drug（100 μg·L-1） were set up in group ， 2 days after intervention of co-culture system， OC was counted， ALP and TRAP in supernatant were detected by microplate enzyme labeling， and the expression of OPG，β-catenin and RANKL in each group was detected by Western blot.Result:Compared with blank group， the ALP activity，β-catenin and OPG protein expression in serum group were significant reduction （P<0.05）， while the OC quantity， TRAP activity and RANKL protein expression were marked increase （P<0.05）. Compared with serum group， ALP activity of icariin group decreased significantly （P<0.01）， Compared with icariin group， ALP activity and OPG protein expression decreased （P<0.05）， trap activity and RANKL expression increased （P <0.05） in icariin + serum group.Conclusion:The serum of kidney Yang deficiency rats can induce the occurrence of osteoporosis， and the mechanism of action may be through inhibition of ALP activity， down regulating the expression of β-catenin and OPG protein， increasing the activity of TRAP and the expression of RANKL protein.