RESUMEN
Objective To study the anti-apoptotic effects of Levodopa on osteonecrosis of the femoral head induced by methylprednisolone (MPS).Methods Forty-four rabbits were randomly divided in to 3 groups.The model group (n=15) was injected with lipopolysaccharide (LPS,10 μg/kg) and then MPS (20 mg/kg) was given 3 times with 24 h interval.The treatment group (n=1 5) was firstly treated by the same methods as the model group,then was administered Levodopa (0.4 g·kg~(-1)·d~(-1)) orally after the last injection of MPS.The control group (n=14) was injected with sodium chloride alone.On the 6th and 8th week after modeling,radiography and MR images were taken in 7 rabbits of each group,specimens taken from the femoral heads were observed by HE stain and TUNEL analysis was made.Blood samples were taken for detection of insulin-like growth factor-1 (IGF-1) on the 8th week.Results On the 6th and 8th week,the average percentage of empty osteocyte lacunae in the treatment group (13.33‰±3.06‰,25.97‰±6.29‰) was significantly lower than that of the model group (21.44‰±4.77‰,33.86‰±8.38‰,P<0.01),and the average apoptosis index in the treatment group (74.93‰±14.32‰,120.67‰±13.13‰) was significantly lower than that of the model group (102.56‰±18.96‰,202.02‰±18.99‰.,P<0.01).On the 8th week,the level of IGF-1 in the treatment group was (14.78±2.37)ng/ml,which was higher than that of the model group obviously (10.12±2.49)ng/ml(P<0.01).Conclusion The Levodopa can decrease apoptosis of osteocytes and effectively prevent the progress of steroid-induced osteonecrosis of the femoral head.