OBJECTIVETo establish the steriod-induced osteoporosis model with the type of Kidney-Yin deficiency.

METHODSTotally 45 female Kunming mice were randomly divided into normal group,model group and Liuwei Dihuang pills(Chinese character: see text)group. The model was established by intramuscular injecting of Dexamethasone. Liuwei Dihuang pills (Chinese character: see text) group was administered orally with Liuwei Dihuang pills (Chinese character: see text). The signs and symptoms of mice were observed dynamically. All the animals were sacrificed at the end of the 6th weeks. The level of ACTH, cAMP, cGMP, TSH and E2 in serum were detected to evaluate deficiency of Kidney-Yin. Morphological changes and bone density were observed to evaluate osteoporosis.

RESULTS(1) Compared with control group, mice in model group appeared obvious Kidney-Yin deficiency symptoms, including hair dry, restlessness, excitability, hard stool, and yellow. (2) Compared with control group,the weight of mice in model group gained slower (P<0.01); the index of adrenal gland,liver and spleen decreased (P<0.01, P<0.01 ,P<0.01); the level of ACTH and TSH increased (P<0.01 ,P<0.01), the level of E2 decreased (P<0.01) and the ratio of cAMP/cGMP increased (P< 0.05). (3)Compared with control group,the bone density of lumbar vertebra and femur in model group were significantly decreased (P<0.01, P<0.05); HE staining revealed osteoporosis in model group mice. (4)However, the Liuwei Dihuang pills (Chinese character: see text) group can partly antagonize the inhibition of the HPA axis, alter the disordered sex hormone and the ratio of cAMP/cGMP, and reverse the osteoporosis partly.

CONCLUSIONthe model of osteoporosis with type of Kidney-Yin deficiency could be established by Dexamethasone intramuscular injection. With less interference, it wight be a stable and reliable modeling method for integration of disease and syndrome in TCM.