Calcified Tissue International

, Volume 40, Issue 3, pp 155–159 | Cite as

Effect of body weight on osteopenia in ovariectomized rats

  • T. J. Wronski
  • P. A. Schenk
  • M. Cintrón
  • C. C. Walsh
Laboratory Investigations


Bilateral ovariectomies or sham surgeries were performed in female Sprague Dawley rats that were 78 days of age and weighed an average of 210 g. Food was available ad libitum to the control rats and to a group of ovariectomized rats (obese OVX). The food consumption of a second group of ovariectomized rats (weight-matched OVX) was restricted to match their body weights to those of the control rats. All rats were sacrificed at 14 weeks postovariectomy. Radioimmunoassay of terminal serum estradiol confirmed the success of ovariectomy. The estradiol concentration in control rats was 24.9±20.2 pg/ml, whereas the hormone was undetectable (<10 pg/ml) in both groups of OVX rats. The final body weights of control and weight-matched OVX rats were nearly identical (∼260 g). In contrast, obese OVX rats weighed significantly more than both of the above groups (∼320 g,P<0.001). The proximal tibia and lumbar vertebra were processed undecalcified for quantitative bone histomorphometry. Tibial trabecular bone volume (TBV) was determined to be 17.6±4.5%, 7.9±5.3%, and 3.6±3.1% for the control, obese OVX, and weight-matched OVX groups, respectively. Tibial TBV for both OVX groups was significantly less than the control value (P<0.001). The difference in tibial TBV between obese OVX and weight-matched OVX rats was also statistically significant (P<0.02). Histologic indices of bone resorption and formation were indicative of increased bone turnover in the proximal tibia of both OVX groups. In comparison to control rats, both groups of OVX rats exhibited a strong trend for a reduction in vertebral TBV, but no significant differences were observed among the three groups. Our results suggest that increased body weight provides partial protection against osteopenia in the long bones of OVX rats. However, it is important to note that this protective effect is only partial and that marked osteopenia develops in the long bones of OVX rats regardless of body weight.

Key words

Quantitative bone histomorphometry Estrogen deficiency Body weight Osteopenia Bone turnover 


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  1. 1.
    Saville PD (1969) Changes in skeletal mass and fragility with castration in the rat: a model of osteoporosis. J Am Geriatr Soc 17:155–164PubMedGoogle Scholar
  2. 2.
    Aitken JM, Armstrong B, Anderson JB (1972) Osteoporosis after oophorectomy in the mature female rat and the effect of estrogen or progestrogen replacement therapy in its prevention. J Endocrinol 55:79–87PubMedCrossRefGoogle Scholar
  3. 3.
    Lindgren JU, Lindholm TS (1979) Effect of 1-alpha-hydroxyvitamin D3 on osteoporosis in rats induced by oophorectomy. Calcif Tissue Int 27:161–164PubMedCrossRefGoogle Scholar
  4. 4.
    Lindgren U, DeLuca HF (1982) Role of parathyroid hormone and 1,25-dihydroxyvitamin D3 in the development of osteopenia in oophorectomized rats. Calcif Tissue Int 34:510–514PubMedCrossRefGoogle Scholar
  5. 5.
    Kalu DN (1984) Evaluation of the pathogenesis of skeletal changes in ovariectomized rats. Endocrinology 115:507–512PubMedGoogle Scholar
  6. 6.
    Wronski TJ, Lowry PL, Walsh CC, Ignaszewski LA (1985) Skeletal alterations in ovariectomized rats. Calcif Tissue Int 37:324–328PubMedGoogle Scholar
  7. 7.
    Wronski TJ, Walsh CC, Ignaszewski LA (1986) Histologic evidence for osteopenia and increased bone turnover in ovariectomized rats. Bone 7:119–123PubMedCrossRefGoogle Scholar
  8. 8.
    Saville PD, Nilsson BER (1966) Height and weight in symptomatic postmenopausal osteoporosis. Clin Orthop 45:49–54PubMedGoogle Scholar
  9. 9.
    Daniell HW (1976) Osteoporosis of the slender smoker. Arch Intern Med 136:298–304PubMedCrossRefGoogle Scholar
  10. 10.
    Lindsay R, Dempster DW, Clemens T, Herrington BS, Wilt S (1984) Incidence, cost, and risk factors of fracture of the proximal femur in the USA. In: Christiansen C, Arnaud CD, Nordin BEC, Parfitt AM, Peck WA, Riggs BL (eds) Osteoporosis I. Glostrup Hospital, Copenhagen, p 311Google Scholar
  11. 11.
    Waynforth HB (1980) Experimental and surgical technique in the rat. Academic Press, New YorkGoogle Scholar
  12. 12.
    Baron R, Vignery A, Neff L, Silvergate A, Santa Maria A (1983) Processing of undecalcified bone specimens for bone histomorphometry. In: Recker RR (ed) Bone histomorphometry: techniques and interpretation. CRC Press, Boca Raton, Florida, p 13Google Scholar
  13. 13.
    Merz WA, Schenk RK (1970) Quantitative structural analysis of human cancellous bone. Acta Anat 75:54–66PubMedGoogle Scholar
  14. 14.
    Frost HM (1983) Bone histomorphometry: analysis of trabecular bone dynamics. In: Recker RR (ed) Bone histomorphometry: techniques and interpretation. CRC Press, Boca Raton, Florida, p 109Google Scholar
  15. 15.
    Duncan RC, Knapp RG, Miller MC (1977) Introductory biostatistics for the health sciences. John Wiley & Sons, New YorkGoogle Scholar
  16. 16.
    Butcher RL, Collins WE, Fugo NW (1974) Plasma concentration of LH, FSH, prolactin, progesterone and estradiol-17B throughout the 4-day estrous cycle of the rat. Endocrinology 94:1704–1708PubMedGoogle Scholar
  17. 17.
    Shires R, Avioli LV, Bergfeld MA, Fallon MD, Slatopolsky E, Teitelbaum SL (1980) Effects of semistarvation on skeletal homeostasis. Endocrinology 107:1530–1535PubMedCrossRefGoogle Scholar
  18. 18.
    Draper HH, Bell RR, Shin KS (1980) Influence of adult age on the skeletal response to phosphate and estrogen in rats. J Nutr 11:778–783Google Scholar
  19. 19.
    Parfitt AM, Mathews CHE, Villanueva AR, Kleerekoper M, Frame B, Rao DS (1983) Relationships between surface, volume, and thickness of iliac trabecular bone in aging and in osteoporosis. Implications for the microanatomic and cellular mechanisms of bone loss. J Clin Invest 72:1396–1409PubMedCrossRefGoogle Scholar
  20. 20.
    Heaney RP, Recker RR, Saville PD (1978) Menopausal changes in bone remodeling. J Lab Clin Med 92:964–970PubMedGoogle Scholar

Copyright information

© Springer-Verlag New York Inc. 1987

Authors and Affiliations

  • T. J. Wronski
    • 1
  • P. A. Schenk
    • 1
  • M. Cintrón
    • 1
  • C. C. Walsh
    • 1
  1. 1.Department of Physiological Sciences, College of Veterinary MedicineJHMHC, University of FloridaGainesville

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