The effect of ipriflavone treatment on osteoporosis induced by immobilization.

The purpose of these experiments was to study the effect of Ipriflavone (7 isopropoxy-isoflavone) on the osteoporosis induced by immobilization. The immobilization was produced by plaster cast of the right hind limb in young and old rats. Ipriflavone was administered via a gastric tube in a daily dose of 40 mg/kg body weight for 8 weeks. On the basis of histological and histomorphometric examinations of the tibia, results of Ipriflavone treatment are the following: 1) The decrease in the density and volume of spongy trabecules was less apparent in both meta- and diaphysis; 2) The amount of persisting cartilage core and structural rarefication of trabecules were diminished; 3) In the metaphysis osteoblastic activity was considerably enhanced; 4) Bone resorption and cortical thinning were decreased; 5) Bone remodeling was increased subperiosteally and to small extent also endosteally; 6) The treatment did not prevent the development of osteoporosis but significantly diminished it.