[Effects of DanShenGuBao on biomechanical properties and bone mineral density of femur induced by retinoic acid in rats].

This investigation was directed to the effects of DanShenGuBao on biomechanical properties and bone mineral density (BMD) of femur induced by retinoic acid (RA) in rats. Forty 4-month-old virgin female Sprague-Dawley rats were randomly divided into 5 groups(8 rats each) control group, RA group and different doses of DanShenGuBao groups. Rats in control group were given vehicle, rats in other four groups were given RA at 70 mg x kg(-1) x d(-1) in the morning and given different drugs in the afternoon at the same time. Rats in RA group were given vehicle, rats in other groups were given different doses of DanShenGuBao which contained 10 mg x kg(-1) x d(-1), 5 mg x kg(-1) x d(-1), 2.5 mg x kg(-1) x d(-1) tanshinol, respectively. All of rats were treated at 5 ml x kg(-1) by oral gavaged for 28 days. In preparation for the determination of dynamic changes in bone tissues, all rats were given subcutaneous injections of 30 mg x kg(-1) tetracycline on the 14th, 13th day and 5 mg x kg(-1) calcein on the 4th, 3rd day before death. At the experimental endpoint, the rats were sacrificed by cardiac puncture under sodium pentobarbital anesthesia. Physical parameters, BMD and biomechanical properties of femur were assessed. Compared with those in control group, the physical parameters (cross-sectional diameter, wet and dry weight), BMD and biomechanical properties (max-load, elasticity-load, break-strain, rigid coefficient and bending-energe) were significantly decreased in RA group. Compared with that in RA group, the BMD of femur was increased significantly in medium and high dose of DanShenGuBao group, but there was no significant change in physical parameters and biomechanical properties of femur. RA could decrease the physical parameters, BMD and biomechanical properties of femur. DanShenGuBao could increase BMD, but it was found with no obvious effect on physical parameters and biomechanical properties.