title: Low-magnitude whole body vibration does not affect bone mass but does affect weight in ovariectomized rats.
abstract: Mechanical loading has stimulating effects on bone architecture, which can potentially be used as a therapy for osteoporosis. We investigated the skeletal changes in the tibia of ovariectomized rats during treatment with whole body vibration (WBV). Different low-magnitude WBV treatment protocols were tested in a pilot experiment using ovariectomized rats with loading schemes of 2 × 8 min/day, 5 days/week (n = 2 rats per protocol). Bone volume and architecture were evaluated during a 10 week follow-up using in-vivo microcomputed tomography scanning. The loading protocol in which a 45 Hz sine wave was applied at 2 Hz with an acceleration of 0.5g showed an anabolic effect on bone and was therefore further analyzed in two groups of animals (n = 6 each group) with WBV starting directly after or 3 weeks after ovariectomy and compared to a control (non-WBV) group at 0, 3, 6 and 10 weeks' follow-up. In the follow-up experiment the WBV stimulus did not significantly affect trabecular volume fraction or cortical bone volume in any of the treatment groups during the 10 week follow-up. WBV did reduce weight gain that was induced as a consequence of ovariectomy. We could not demonstrate any significant effects of WBV on bone loss as a consequence of ovariectomy in rats; however, the weight gain that normally results after ovariectomy was partly prevented. Treatment with WBV was not able to prevent bone loss during induced osteoporosis.
authors.affiliation: Department of Orthopaedics, Erasmus MC, University Medical Center Rotterdam, Dr. Molenwaterplein 40, Room 16.14, PO box 2040, 3000 CA Rotterdam, The Netherlands. o.vanderjagt@erasmusmc.nl
authors.forename: Olav P
authors.initials: OP
authors.lastname: van der Jagt
authors.forename: Jacqueline C
authors.initials: JC
authors.lastname: van der Linden
authors.forename: Jan H
authors.initials: JH
authors.lastname: Waarsing
authors.forename: Jan A N
authors.initials: JA
authors.lastname: Verhaar
authors.forename: Harrie
authors.initials: H
authors.lastname: Weinans
mesh_terms: D000818:Animals; D001835:Body Weight / Q000502:physiology*; D001842:Bone and Bones / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D009929:Organ Size / Q000502:physiology; D010052:Ovariectomy; D010865:Pilot Projects; D051381:Rats; D017208:Rats, Wistar; D014732:Vibration; D015430:Weight Gain / Q000502:physiology; D055114:X-Ray Microtomography