Abstract: Objective To observe and compare the effects of different modeling methods of osteoporosis on rats. Methods Female SD rats at age of six months were divided into normal group, ovariectomized group, glucocorticoid group, and retinoic acid group. After 6 weeks, the changes of serum calcium, phosphorus, alkaline phosphatase and bone density, bone histomorphometry parameters were compared. Results Compared with normal group, the serum Ca in ovariectomized rats was decreased, serum P and ALP were increased, bone mineral density, trabecular thickness and trabecular number were decreased, and trabecular spacing was increased.The Glucocorticoid group compared with normal group, there was no significant difference in each parameters. Compared with the normal group, retinoic acid rat’s serum Ca was decreased, serum P and ALP were increased,bone mineral density, trabecular thickness and trabecular number were decreased, and trabecular spacing was increased. Conclusion The osteoporotic model was successful.With the short-term intermittent use of glucocorticoid, effects on the cancellous bone in rats may not be obvious, large dose of retinoic acid can reduce bone mass of rats in short-term and change the bone micro structural, but it had obvious side effects.

Key words: Osteoporosis, Ovariectomy, Glucocorticoid, Retinoic Acid, Rat Model