title: Intermittent weekly administration of human parathyroid hormone (1-34) improves bone-hydroxyapatite block bonding in ovariectomized rats.
abstract: Hydroxyapatite (HA) blocks have been widely used for the reconstruction of bone defects and as a bone substitute. Bone-implant bonding depends on both implant-related factors and patient variables. Intermittent human parathyroid hormone (h-PTH) has a strong anabolic effect on bone formation. The purpose of the present study is to evaluate whether intermittent h-PTH administration enhances bone-HA block bonding in normal versus ovariectomized (OVX) rats. Cancellous bone osteotomy and HA-block implantation were performed on the proximal left tibia in both OVX and sham-operated 7-month-old female Sprague-Dawley rats. Newly formed cancellous bone around the HA block and bone-HA block bonding were evaluated by bone histomorphometry at 8 weeks after the administration of h-PTH (100 μg/kg/week) or its vehicle. The administration of h-PTH significantly increased cancellous bone volume by stimulating bone formation in OVX rats (p < 0.01). Although bone-HA block bonding was significantly decreased in OVX rats compared to that of sham-operated rats (p < 0.01), h-PTH improved the bone-HA block bonding in OVX rats (p < 0.01). These results suggest that intermittent h-PTH treatment may improve bone-HA bonding in osteoporosis by restoring cancellous bone volume and enhancing cancellous bone formation around the HA block.
authors.affiliation: Department of Orthopedic Surgery, Akita University Graduate School of Medicine, 1-1-1 Hondo, Akita, Japan. kamokamo@doc.med.akita-u.ac.jp
authors.forename: Keiji
authors.initials: K
authors.lastname: Kamo
authors.forename: Naohisa
authors.initials: N
authors.lastname: Miyakoshi
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kasukawa
authors.forename: Koji
authors.initials: K
authors.lastname: Nozaka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sasaki
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Shimada
mesh_terms: D000818:Animals; D050071:Bone Density Conservation Agents / Q000008:administration & dosage* / Q000627:therapeutic use*; D001862:Bone Resorption / Q000517:prevention & control; D018786:Bone Substitutes / Q000627:therapeutic use*; D017886:Durapatite / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007717:Knee; D010012:Osteogenesis / Q000187:drug effects; D010024:Osteoporosis / Q000188:drug therapy / Q000473:pathology / Q000628:therapy; D015663:Osteoporosis, Postmenopausal / Q000188:drug therapy* / Q000473:pathology / Q000628:therapy; D010052:Ovariectomy; D051381:Rats; D017207:Rats, Sprague-Dawley; D019379:Teriparatide / Q000008:administration & dosage* / Q000627:therapeutic use*; D013977:Tibia / Q000187:drug effects / Q000473:pathology
chemical_list: D050071:Bone Density Conservation Agents; D018786:Bone Substitutes; D019379:Teriparatide; D017886:Durapatite