Abstract: Objective: To explore the therapeutic effect of cistanche deserticola ethanol extraction (CDE) in the rats with osteoporosis induced by ovariectomy,and to clarify its mechanism. Methods: A total of 72 female SD rats were randomly divided into control,model,estradiol (0.3 g·kg^-1),low, middle and high doses(0.5,1.0 and 2.0 mg·kg^-1)of CDE groups,and 12 rats in each group.The rat ovaries were removed by operation in the other groups to establish the osteoporosis models,while the same size of fat of the rats in control group was excised.5 d later,the rats in estradiol group were hypodermicly injected with estradiol,and the rats in CDE groups were orally administrated with corresponding doses of CDE.The same volume of diluted water was given to the rats in control and model groups.After 20 weeks,the density of right femur of the rat was detected with the method of ratio of weight and size; the mechanics index of left femur of the rat was analyzed by bone granulometer; the levels of serum alkaline phosphatase (ALP)and osteocalcin were measured by ELISA; the levels of serum Ca²⁺ and P were detected by automatic biochemical analyzer; the morphology of uterus tissue was observed by HE staining. Results: Compared with model group,the densities of right thighbone of the rats in estradiol group and low,middle and high doses of CDE groups were significantly increased (P<0.05 or P<0.01); there were no differences between low,middle and high doses of CDE groups (P>0.05).Compared with model group and low dose of CDE group,the maximum bending forces,the maximun strains,and the bone rigid coefficients in middle and high doses of CDE groups were remarkably increased (P<0.05),while the levels of ALP were decreased (P<0.05).Compared with model group,and low and middle doses of CDE groups,the level of osteocalcin in high dose of CDE group was significantly decreased(P<0.05).Compared with model group,the levels of Ca²⁺ in serum of the rats in low, middle and high doses of CDE groups were significantly increased (P<0.05); there were no significant differences between low,middle and high doses of CDE groups (P>0.05).Compared with model group,the morphology of uterus tissue of the rats in low,middle and high doses of CDE groups was improved at different degrees. Conclusion: CDE has therapeutic effect on osteoporosis through increasing the levels of serum ALP,osteocalcin and Ca²⁺ of the rats.

Key words: cistanche deserticola, alkaline phosphatase, calcium ion, osteocalcin, ethanol extraction