Author/Authors :
Yang، Y. نويسنده , , Lee، H.J. نويسنده , , Jang، H. G. نويسنده , , Lee، J.H. نويسنده , , Moon، C. نويسنده Chonnam National University Moon, C. , Kim، J.C. نويسنده , , Jung، U. نويسنده Advanced Radiation Technology Institute, KAERI Jung, U. , Jo، S.K. نويسنده Advanced Radiation Technology Institute, KAERI Jo, S.K. , Kang، C.M. نويسنده Korea Institute of Radiological & Medical Science Kang, C.M. , Kim، S.H. نويسنده ,
Abstract :
Background: The trabecular bone changes in the tibia of C3H/HeN mice were measured 12 weeks after whole body irradiation with various doses of fast neutrons (0-2.4 Gy) or 137Cs-generated gamma-rays (0-6 Gy). Materials and Methods: Serum calcium, phosphorus, estradiol concentration and alkaline phosphatase activity were measured. Tibiae were analyzed using microcomputed tomography. Biomechanical property and osteoclast surface level were measured. Results: There was a significant relationship between the loss of bone architecture and the radiation dose, and the best-fitting dose-response curves were linear-quadratic. Mean relative biological effectiveness (RBE) values (Ref. gamma) of 2.05 and 2.33 were estimated for fast neutron irradiation in trabecular bone volume fraction and bone mineral density, respectively. There was a substantial reduction in osteoclast surface level in tartrate-resistant acid phosphatase-stained histological sections of tibial metaphyses in irradiated mice with high dose of neutrons. Conclusion: There was a significant relationship between the loss of bone architecture and the radiation dose. The difference of osteoclastic bone resorption may represent a contributor to the low RBE in high dose of irradiation level relative to that of low dose level.
