Bipedal stance exercise and prostaglandin E2 (PGE2) and its synergistic effect in increasing bone mass and in lowering the PGE2 dose required to prevent ovariectomized-induced cancellous bone loss in aged rats

A. Mo, Wei Yao, C. Li, X. Tian, M. Su, Y. Ling, Q. Zhang, R. B. Setterberg, W. S S Jee

Research output: Contribution to journalArticle

27 Scopus citations


Previous reports have shown that bone loss was partially prevented by bipedal stance "exercise" following ovariectomy (ovx), and it was well documented that prostaglandin E2 (PGE2) had an anabolic effect on the rat skeleton. The aim of this study was to determine whether lower doses of PGE2 could prevent ovx-induced cancellous bone loss with the combination of bipedal stance exercise. Seventy-eight 10-month-old female Sprague-Dawley rats were either ovariectomized or sham-operated on day 0 and then treated with PGE2 (0, 0.3, or 1 mg/kg per day) and/or housed in normal height cages (NC, 28 cm) or raised cages (RC, 33 cm) for 8 weeks. Bone histomorphometry was performed on the double-fluorescent-labeled proximal tibial metaphysis. In sham rats, 1 mg/kg PGE2 + RC had synergistic effects in increasing trabecular bone area, width, and number by stimulating mineral apposition rate and bone formation rate. As expected, ovx induced cancellous bone loss, accompanied by elevated activation frequency. Without RC, PGE2 monotherapy prevented ovx-induced bone loss at the 1 mg/kg per day dose, whereas this prevention effect was observed at the 0.3 mg/kg per day dose when combined with RC. Similar to their effects in sham rats, PGE2 and RC had synergistic effects in augmenting cancellous bone mass and architecture and maintaining the elevated bone formation but depressing bone resorption and activation frequency. We conclude that bipedal stance exercise lowers the PGE2 dose required to prevent ovx-induced cancellous bone loss in the proximal tibial metaphysis in aged rats.

Original languageEnglish (US)
Pages (from-to)402-406
Number of pages5
Issue number3
StatePublished - Sep 2002
Externally publishedYes



  • Bipedal stance exercise
  • Cancellous bone
  • Histomorphometry
  • Ovariectomy (ovx)
  • Prostaglandin estradiol (PGE)

ASJC Scopus subject areas

  • Physiology
  • Hematology

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