title: Long-term therapeutic effect of novel calcium phosphate-based compounds injected in ovariectomized rats.
abstract: The specific aim of this study was to evaluate the efficacy of well-characterized Mg/Zn/F-CaP preparations (administered by injection) in preventing bone mineral deficiency in ovariectomized (OVX) rats. Donryu rats (4 weeks old, average weight 70 g) were divided into six experimental groups: GN (normal), GC (control, OVX), and OVX rats injected with suspensions of MZF-CaPs (G2, G3, and G4) or with Zn-containing tricalcium phosphate (ZnTCP, G1). The composition of the preparations was G1: 34.1 wt % Ca; 19.5 wt % P; and 6.17 wt % Zn; G2 (#51): 23.7 wt % Ca; 13.6 wt % P; 1.1 wt % Mg; 2.9 wt % Zn, and 1.1 wt % F; G3 (#68): 22.4 wt % Ca; 14.1 wt % P; 2.6 wt % Mg, 2.6 wt % Zn, and 2.3 wt % F; G4 (#76): 28.5 wt % Ca; 15.5 wt % P; 1.9 wt % Mg, 1.8 wt % Zn, and 3.0 wt % F. The suspensions (10 mg/0.2 mL) were injected into the right thigh once a week for 12 weeks. Bone mineral density (BMD) was measured by X-ray computed tomography and bone mechanical strength (BMS) was measured as femoral three-point bending strength. BMD and BMS were significantly higher in the femurs from groups G1, G2, G3, and G4 than from GC. No significant difference was observed in BMD or BMS between the left and right femurs for any group. The results indicate that the injected Mg/Zn/F-CaP compounds were effective in preventing bone loss induced by ovariectomy in rats and suggest that these compounds have potential use for treating osteoporosis.
authors.affiliation: Research Institute of Pharmaceutical Sciences, Faculty of Pharmacy, Musashino University, Tokyo, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Tokudome
authors.forename: Makoto
authors.initials: M
authors.lastname: Otsuka
authors.forename: Atsuo
authors.initials: A
authors.lastname: Ito
authors.forename: Racquel Z
authors.initials: RZ
authors.lastname: LeGeros
mesh_terms: D000818:Animals; D001835:Body Weight; D015519:Bone Density; D002130:Calcium Phosphates / Q000008:administration & dosage*; D005260:Female; D010052:Ovariectomy; D051381:Rats; D014057:Tomography, X-Ray Computed; D014961:X-Ray Diffraction
chemical_list: D002130:Calcium Phosphates; C020243:calcium phosphate