Abstract

The purpose of these experiments was to test the hypothesis that estrogen has an anabolic effect on cancellous bone formation in long bones of growing rats. In the present studies, estrogen decreased measurements related to cancellous bone formation, including osteoblast number, fluorochrome-labeled bone perimeter, and incorporation of [3H]proline into osteoid. Steady state mRNA levels for bone matrix proteins and mineral apposition rate were unchanged or reduced. The [3H]thymidine labeling index for osteoblasts was very low and was reduced by estrogen treatment. Finally, estrogen decreased the rate of removal of tetracycline previously incorporated into cancellous bone as well as the growth-dependent decrease in cancellous bone area, indicating that hormone treatment reduced net bone resorption. In summary, no evidence was secured to support the hypothesis that estrogen has an anabolic action on bone formation; the results obtained in these studies consistently demonstrated a pronounced inhibitory action of the hormone on bone turnover.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.