Effects of PTH treatment on tibial bone of ovariectomized rats assessed by in vivo micro-CT
| Autor: | Rik Huiskes, Julienne E.M. Brouwers, B. van Rietbergen, Keita Ito |
|---|---|
| Přispěvatelé: | Orthopaedic Biomechanics |
| Rok vydání: | 2009 |
| Předmět: |
endocrine system
Pathology medicine.medical_specialty X-ray microtomography Bone density Ovariectomy In vivo micro-CT Endocrinology Diabetes and Metabolism Osteoporosis Drug Evaluation Preclinical Parathyroid hormone Bone remodeling Bone Density In vivo Animals Medicine Rats Wistar Bone Density Conservation Agents Tibia business.industry X-Ray Microtomography medicine.disease Rats Rat ovariectomy model Bone Diseases Metabolic Disease Models Animal Bone microstructure Parathyroid Hormone Ovariectomized rat Female Original Article Bone Remodeling Diaphyses business Epiphyses hormones hormone substitutes and hormone antagonists PTH |
| Zdroj: | Osteoporosis International, 20(11), 1823-1835. Springer Osteoporosis International |
| ISSN: | 1433-2965 0937-941X |
| DOI: | 10.1007/s00198-009-0882-5 |
| Popis: | Summary: Using in vivo microcomputed tomography (micro-CT), we found in parathyroid hormone (PTH)-treated osteopenic rats linear increases in cortical and trabecular, due to increased trabecular thickness and number, bone mass. Bone was formed in cavities, leading to restoral of nearly cleaved trabeculae. For the first time, effects in PTH-treated rats were analyzed longitudinally. Introduction: Our aims were to over time (1) determine changes in trabecular thickness and number after PTH, (2) compare responses to PTH between the meta- and epiphysis, (3) determine effects of PTH on mineralization and mechanical properties, (4) determine locations of new bone formation due to PTH on a microlevel, and (5) determine the predictive value of bone structural properties for gain in bone mass after PTH. Methods: Adult rats were divided into ovariectomy (OVX; n = 8), SHAM-OVX (n = 8), and OVX and PTH treatment (n = 9). Between weeks 8 and 14, PTH rats received daily subcutaneous PTH injections (60 µg/kg/day). At weeks 0, 8, 10, 12, and 14, in vivo micro-CT scans were made of the proximal and diaphyseal tibia. After sacrifice, all tibiae were tested in three-point bending. Results: PTH increased bone volume fraction linearly over time in meta- and epiphysis, accompanied by increased trabecular thickness in both and increased trabecular number only in the latter one. CT-estimated mineralization increased in trabecular and remained constant in cortical bone. Ultimate load and energy were increased and ultimate displacement and stiffness unaltered compared to SHAM rats. For those trabeculae analyzed, bone was formed initially on places where it was most beneficial for increasing their strength and later on to all surfaces. © 2009 The Author(s). |
| Databáze: | OpenAIRE |
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