Objective: To explore the mechanism of inhibiting the bone injury by Fuzi Baizhu decoction in bone metastases of breast cancer by regulating osteoprotegerin(OPG)/receptor activator of nuclear-κB ligand(RANKL). Method: The model of breast cancer bone metastases was established by injecting the MDA-MB-231BO cells into left ventricle. 24 nude mice in model group were divided into model group

zoledronic acid group

Fuzi Baizhu decoction group and rhizoma atractylodis macrocephalae-radix aconiti carmichaeli group randomly

and another 6 normal unde mice were as normal group (n=6). Four days after the modeling

the drug intervention was carried out respectively:zoledronic acid group was treated with

zoledronic acid

0.2 mg·kg-1;model group

rhizoma atractylodis macrocephalaeradix aconiti carmichaeli decoction group

rhizoma atractylodis macrocephalae-radix aconiti carmichaeli group and normal group:normal sodium(NS) 20 mL·kg-1

Fuzi Baizhu decoction 5.6 g·kg-1

rhizoma atractylodis macrocephalae-radix aconiti carmichaeli 2.4 g·kg-1 and NS 20 mL·kg-1 merely

po;3 times every week

lasting 6 weeks. The weight

pathology of bone metastases focus were observed and OPG mRNA and RANKLmRNA expression was detected. Result: ①In the model group

the number and rate of bone metastases and weight loss of the pair of rhizoma atractylodis macrocephalae and radix aconiti carmichaeli group and Fuzi Baizhu decoction group declined obviously(P<0.05)

the number of TRAP(+) reduced in the bone metastases (P<0.01)

the OPGmRNA relative expression content increased (P<0.01)

the RANKLmRNA relative expression content and ratio declined obviously (P<0.01);② In the group of the Fuzi Baizhu decoction

the number and the rate of bone metastases

the rate of weight loss

the number of TRAP(+)

the OPGm RNA and the RANKL mRNA relative expression content and ratio had no statistically significant differences between rhizoma atractylodis macrocephalae and radix aconiti carmichaeli group. Conclusion: Both decoction of rhizoma atractylodis macrocephalae and radix aconiti carmichaeli and the pair of Rhizoma Atractylodis Macrocephalae and radix aconiti carmichaeli could regulate OPG/RANKL

decrease osteoclast and restrain activity of them

reduce osteolytic damage accordingly.