Prostaglandin E2 administration prevents bone loss induced by orchidectomy in rats.
The objects of this study were to investigate whether prostaglandin E2 (PGE2) can prevent orchidectomy (ORX)-induced cancellous bone loss in growing male rats, and to determine the differential effects of PGE2 on sham-operated (sham) and ORX male rats. Fourteen-week-old Sprague-Dawley male rats were divided into groups of basal, vehicle-treated sham, PGE2-treated sham, vehicle-treated ORX, and PGE2-treated ORX rats for either 3 or 9 weeks. PGE2 was given at 6 mg/kg body weight daily by subcutaneous injection. Static and dynamic cancellous bone histomorphometry were performed on double-fluorescent labeled undecalcified proximal tibial metaphyseal sections. No effect was observed by ORX on body weight or longitudinal bone growth rate when compared with sham-operated controls. However, androgen deficiency caused significant increases in percent eroded perimeter, mineral apposition rate, and bone turnover (bone-volume-referent-bone formation rate), which resulted in a significant decrease in trabecular bone number, increase in trabecular separation, and a nonsignificant decrease in trabecular bone area by 3 weeks of ORX. After 9 weeks of ORX, trabecular bone area and number were significantly decreased, and trabecular separation, percent eroded perimeter, and the index of bone turnover (bone-volume-referent-bone formation rate) remained significantly increased while the index of bone formation (tissue-volume-referent-bone formation rate) was nonsignificantly decreased when compared with sham controls. When 6 mg PGE2/kg/day was given for 3 and 9 weeks, similar anabolic effects were observed in sham and ORX rats.(ABSTRACT TRUNCATED AT 250 WORDS)
Li
M
M
Division of Radiobiology, University of Utah School of Medicine, Salt Lake City 84112, USA.
Jee
W S
WS
Ke
H Z
HZ
Tang
L Y
LY
Ma
Y F
YF
Liang
X G
XG
Setterberg
R B
RB
D000375:Aging / Q000473:pathology*; D000704:Analysis of Variance; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D015519:Bone Density / Q000187:drug effects*; D001846:Bone Development / Q000187:drug effects; D015232:Dinoprostone / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D007091:Image Processing, Computer-Assisted; D007279:Injections, Subcutaneous; D008297:Male; D009919:Orchiectomy / Q000009:adverse effects*; D010024:Osteoporosis / Q000209:etiology / Q000517:prevention & control*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013977:Tibia / Q000187:drug effects / Q000502:physiology
D015232:Dinoprostone