title: BMP-2 release and dose-response studies in hydroxyapatite and beta-tricalcium phosphate.
abstract: The purpose of this study is to compare in vivo retention of BMP-2 and bone induction in HAp (porosity: 60-80%, pore size: 100-600 mum, sintering temperature: 800 degrees C, surface area: 1 m(2)/g) and beta-TCP (porosity: 75%, pore size: 100-400 mum, sintering temperature: 1050 degrees C, surface area: 4 m(2)/g). We estimated the in vivo release profile of (125)I-labeled BMP-2 and bone induction of hard tissues histologically. The amount of BMP-2 remaining in the beta-TCP at 1 day after implantation was 49.6%, while the amount was 34.0% in the HAp. Furthermore, the HAp and beta-TCP containing 0.0, 0.05, 0.1, 0.3, 0.5, 1.0, 5.0 microg of BMP-2 were implanted into the back subcutis of 4-week old Wistar rats. At 3 weeks after implantation, the ceramics were explanted and evaluated histologically. The HAp/BMP-2 (5.0 microg) system showed 3.0% in the total volume of bone at 3 weeks, while only in the beta-TCP/BMP-2 (5.0 microg) system showed 32.5%. These results indicate that the absorbable beta-TCP block may be an effective bioceramic for bone induction to deliver BMP-2 to the site of action.
authors: Health Sciences University of Hokkaido, Hokkaido, Japan. j-tazaki@hoku-iryo-u.ac.jp
authors: Junichi
authors: J
authors: Tazaki
authors: Masaru
authors: M
authors: Murata
authors: Toshiyuki
authors: T
authors: Akazawa
authors: Masaya
authors: M
authors: Yamamoto
authors: Katsutoshi
authors: K
authors: Ito
authors: Makoto
authors: M
authors: Arisue
authors: Takanori
authors: T
authors: Shibata
authors: Yasuhiko
authors: Y
authors: Tabata
mesh_terms: D000042:Absorption; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D055396:Bone Morphogenetic Protein 2 / Q000008:administration & dosage / Q000737:chemistry* / Q000493:pharmacokinetics*; D002130:Calcium Phosphates / Q000737:chemistry*; D002417:Cattle; D003460:Crystallization / Q000379:methods; D003692:Delayed-Action Preparations / Q000737:chemistry*; D004058:Diffusion; D017886:Durapatite / Q000737:chemistry*; D008422:Materials Testing; D051379:Mice; D010012:Osteogenesis / Q000187:drug effects / Q000502:physiology*; D010316:Particle Size; D016062:Porosity; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics; D013499:Surface Properties
chemical_list: C525718:BMP2 protein, human; D001672:Biocompatible Materials; D055396:Bone Morphogenetic Protein 2; D002130:Calcium Phosphates; D003692:Delayed-Action Preparations; D011994:Recombinant Proteins; C485817:beta-tricalcium phosphate; D017886:Durapatite