Effect of risedronate on bone mass, remodelling and biomechanical strength in orchidectomized rats.
BACKGROUND
The ability of risedronate to prevent and/or treat orchidectomy-induced osteoporosis in male rats was studied.


METHODS
Ninety-five 10-week-old male Wistar rats were sham-operated or orchidectomized. Prevention study: Sham: sham-operated rats; ORX: orchidectomized rats; ORX + RSD: orchidectomized rats, treated for 6 weeks with risedronate. Animals were sacrificed 6 weeks after surgery. Treatment study: Sham(1) and ORX(1): sham and orchidectomized rats sacrificed 3 months after orchidectomy; Sham(2), ORX(2) and ORX(2) + RSD: sham-operated, and orchidectomized rats treated with placebo or risedronate for 6 weeks starting 3 months after orchidectomy, and then sacrificed. Risedronate (0.5 mg/kg/day) and placebo (saline) were administered via oral gavage. After sacrifice, bone mineral density by DEXA, bone volume (BV/TV), osteocalcin (BGP), and serum carboxyterminal telopeptide of collagen type I (CTX) were measured. Femur low-rate torsion testing was performed.


RESULTS
Orchidectomy produced an increase in bone remodelling with loss of BV/TV, without effects on torsional strength. Risedronate treatment partially prevented these effects. In the treatment study, risedronate reduced bone remodelling and restored BV/TV to levels higher than those of the sham group, improving biomechanical parameters.


CONCLUSIONS
These results suggest that risedronate could be used as a prevention or treatment of male osteoporosis due to hypogonadism.
Díaz-Curiel
M
M
Internal Medicine, Fundación Jiménez Díaz, Madrid, Spain.
de la Piedra
C
C
Romero
F I
FI
Montero
M
M
Gómez
S
S
Lefort
M
M
Carrascal
M T
MT
Phipps
R J
RJ
D000818:Animals; D015519:Bone Density / Q000187:drug effects; D016723:Bone Remodeling / Q000187:drug effects*; D001842:Bone and Bones / Q000033:anatomy & histology / Q000187:drug effects*; D012968:Etidronic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D008297:Male; D009919:Orchiectomy; D051381:Rats; D017208:Rats, Wistar; D000068296:Risedronic Acid
D000068296:Risedronic Acid; D012968:Etidronic Acid