Effects of stanozolol on bone mineral density and bone biomechanical properties of osteoporotic rats

doi:10.3321/j.issn:1673-4254.2003.11.001

Abstract：Objective To evaluate the effects of stanozolol on the bone mineral density (BMD) and bone biomechanical prop-erties of rats with glucocorticoid (GC)-induced osteoporosis (OP). Methods Twenty-eight male Sprague-Dawley rats of3-month old were randomly divided into Group A (the basal control group), Group B (the age-matched control group), GroupC (GC-induced OP group) and Group D (stanozolol-administtated group), 7 in each group. The rats in Group A were killedwhen experiment commenced, and those in Group B were given normal saline ig., while those in Groups C and D received theprednisone acetate (4.5 mg/kg, twice a week) alone and in combination with stanozolol (0.5 mg/kg, 6 times a week), respec-tively. Ninety days later, the bilateral femur and the 5th lumbar vertebra of the rats were isolated for BMD test using dual-en-ergy X-ray absorptiometry scanner, and the torsion test, three-point bending test and compression test using electronic testingdevice. Results Compared with Group B, the mean BMD of the femur and the 5th lumbar vertebra in Group C decreased by14.64% (P＜0.01), the BMD of the bilateral distal femoral segment and the 5th lumbar vertebra decreased by 21.42% (P＜0.01),19.62% (P＜0.05) and 23.48% (P＜0.01) respectively. The load that the femur withstood in three-point bending test decreasedby 17.1% (P＜0.05), and the other biomechanical parameters also declined. When compared with Group C, the BMD in GroupD increased, the torsional angle of the femur increased by 72.5% (P＜0.05) and the other biomechanical parameters also tendedto increase. Conclusions BMD and biomechanical properties of the rat femur and the 5th lumbar vertebra decrease in re-sponse to a long-term GC administration, which can be prevented by stanozolol.