We examined changes in bone mineral content (BMC) of the mandible and interleukin-6 (IL-6) production from bone marrow cells in ovariectomized (OVX) rats administered bisphosphonate.
Six-week-old SD female rats after OVX or sham operation were injected with incadronate (10 or 30μg/100g body weight: BW) as bisphosphonate or estradiol (400μg/100g BW) subcutaneously 3 days a week for 4 weeks.
Both incadronate and estradiol inhibited the increase of total body weight and the decrease of BMC of the mandible and humerus in OVX-rats. The increase of IL-6 release from bone marrow cells in the non-treated group by stimulation with LPS was suppressed in theincadronate group as well as the estradiol group. A dose-dependent effect was found in IL-6 release and BMC in the incadronate-group. However, although the increase of serum Ca level in OVX-rats was inhibited by incadronate and estradiol administration, there was a difference in alkaline phosphatase (AL-P) activity between both groups.
These results suggest that incadronate increases the BMC through an alternative mechanism compared with estradiol.
