To inquire into the relationship between pathogenesis of osteoporosis and changes of MDA and SOD, the plasma levels of MDA and SOD in ovariectomized rat models of osteoporosis were measured and compared with those of the normal or sham surgery group. The results showed much higher MDA of the ovariectomized group than that of the control and lower SOD of the ovariectomized group than that of the normal control group with a very significant and significant difference (P < 0.01 and P < 0.05), suggesting the definite role of MDA and SOD...