J Korean Orthop Res Soc.  2003 Apr;6(1):35-46.

Experimental Osteoporosis in Tail Suspended Rat

• Chung ER
• Chun JM
• Chang JS
• Shon HC
• Kim JH
• Lee SW

Abstract

PURPOSE
To clarify whether the bone resorption in femur measured by the expression of OPG & RANK-L was increased in tail suspended rat.
MATERIALS AND METHODS
Four-week-old female Sprague Dawley rats were divided into two groups. The experimental group (n=79) was housed and fed with 2 weeks of tail suspension, and reloaded for 8 weeks without tail suspension. The control group (n=46) was housed and fed for 10 weeks without tail suspension. Bone mineral densities, serum levels of ALP and TRAP were measured in both groups. The expressions of the mRNAs of OPG and RANK-L were analyzed by RT-PCR. RESULTS: The ALP and TRAP were increased in the experimental group during both tail suspension and reloading, which reflected the increased bone metabolism in the experimental group. In femur of the experimental group, the expression of the mRNA of RANK-L was increased during tail suspension, and the expression the mRNA of OPG was decreased. With reloading, the expression of the mRNA of RANK-L in femur was decreased, while the expression of the mRNA of OPG was increased.

Keyword

Osteoporosis; Skeletal unloading; Osteoclast; Receptor Activator of Nuclear Factor- kappaB Ligand(RANK-L); Osteoprotegerin

MeSH Terms

Animals
Bone Density
Bone Resorption
Female
Femur
Hindlimb Suspension
Humans
Metabolism
Osteoclasts
Osteoporosis*
Osteoprotegerin
Rats*
Rats, Sprague-Dawley
RNA, Messenger
Tail*
Osteoprotegerin
RNA, Messenger