Prostaglandin E2 adds bone to a cancellous bone site with a closed growth plate and low bone turnover in ovariectomized rats

Bone. 1994 Mar-Apr;15(2):137-46. doi: 10.1016/8756-3282(94)90700-5.

Abstract

The objects of this study were to determine the responses of a cancellous bone site with a closed growth plate (the distal tibial metaphysis, DTM) to ovariectomy (OVX) and OVX plus a prostaglandin E2 (PGE2) treatment, and compare the site's response to previous findings reported for another site (the proximal tibial metaphysis, PTM). Thirty-five 3-month-old female Sprague-Dawley rats were divided into five groups: basal, sham-OVX, and OVX + 0, +1, or +6 mg PGE2/kg/d injected subcutaneously for 3 months and given double fluorescent labels before sacrifice. Cancellous bone histomorphometric analyses were performed on 20-microns-thick undecalcified DTM sections. Similar to the PTM, the DTM showed age-related decreases in bone formation and increases in bone resorption, but it differed in that at 3 months post-OVX, there was neither bone loss nor changes in formation endpoints. Giving 1 mg PGE2/kg/d to OVX rats prevented most age-related changes and maintained the bone formation histomorphometry near basal levels. Treating OVX rats with 6 mg PGE2/kg/d prevented age-related bone changes, added extra bone, and improved microanatomical structure by stimulating bone formation without altering bone resorption. Furthermore, after PGE2 administration, the DTM, a cancellous bone site with a closed growth plate, increased bone formation more than did the cancellous bone in the PTM.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Analysis of Variance
  • Animals
  • Bone Development / drug effects*
  • Bone Resorption / drug therapy
  • Dinoprostone / pharmacology*
  • Dinoprostone / therapeutic use
  • Female
  • Growth Plate / drug effects*
  • Microscopy, Fluorescence
  • Ovariectomy
  • Rats
  • Rats, Sprague-Dawley
  • Tibia / anatomy & histology
  • Tibia / drug effects

Substances

  • Dinoprostone