Laboratory Animals > Volume 43, Number 3 > Pp. 266-271

This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: la.2008.008045v1 43/3/266    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Leitner, M M Articles by Ito, K Search for Related Content PubMed PubMed Citation Social Bookmarking                      What's this?

Original Articles

Longitudinal as well as age-matched assessments of bone changes in the mature ovariectomized rat model

M M Leitner ¹, A E Tami ¹ , P M Montavon ² and K Ito ^1 3

¹ AO Research Institute, AO Foundation, Clavadelerstrasse 8, 7270 Davos, Switzerland; ² Veterinary Clinic for Small Animal Surgery, University of Zurich, Switzerland; ³ Department of Biomedical Engineering, Eindhoven University of Technology, The Netherlands

Corresponding author: Andrea E Tami. Email: andrea.tami{at}aofoundation.org

In the past, bone loss in the ovariectomized (OVX) osteoporotic rat model has been monitored using in vitro micro-computed tomography (micro-CT) to assess bone structure (bone volume/total volume, BV/TV). The purpose of this study was to assess the importance of baseline control and sham groups in 12–16-week-old, reproductively mature rats. Measurements were carried out in a longitudinal and age-matched fashion using newer in vivo peripheral quantitative computed tomography (pQCT), which measures apparent bone mineral density (BMD). BMD was measured at the distal femoral metaphysis of 12-week-old female Wistar rats with pQCT. Subsequently, animals were either OVX or sham operated, and pQCT measurements were repeated four weeks later. Then, all rats were euthanized and in vitro BMD and BV/TV were obtained by micro-CT imaging. Results from three consistently differentiated regions of interest showed that there was significant bone loss and growth during the four weeks in the OVX and sham group, respectively. Taking this into account, i.e. a posteriori superimposing growth to loss, no differences resulted between BMD values measured in a longitudinal fashion with pQCT and that measured in comparison with an age-matched sham group with micro-CT and pQCT. In addition, there was a strong linear correlation between BMD measured with pQCT and BV/TV obtained from micro-CT. In conclusion, this outcome provides new insights into individual bone changes due to OVX and growth in Wistar rats during the age period of 12–16 weeks, which is often applied in osteoporosis research as the ‘mature’ rat model. Data can be used as baseline information upon which future in vivo study designs with this rat model can refer to reduce and minimize animal use.

Key Words: Experimental design • rat model • in vivo • osteoporosis • computed tomography

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?