TY - JOUR
T1 - Quantification of skeletal blood flow and fluoride metabolism in rats using PET in a pre-clinical stress fracture model
AU - Tomlinson, Ryan E.
AU - Silva, Matthew J.
AU - Shoghi, Kooresh I.
N1 - Funding Information:
Acknowledgments. Funded by a grant from the National Institutes of Health (AR050211). The authors would like to acknowledge Nikki Fettig, Lori Strong, Dr. Richard Laforest, and JR Rutlin for their assistance in PET scanning. Mechanical loading performed in facilities supported by the Washington University Center for Musculoskeletal Research (P30AR057235).
PY - 2012/6
Y1 - 2012/6
N2 - Purpose: Blood flow is an important factor in bone production and repair, but its role in osteogenesis induced by mechanical loading is unknown. Here, we present techniques for evaluating blood flow and fluoride metabolism in a pre-clinical stress fracture model of osteogenesis in rats. Procedures: Bone formation was induced by forelimb compression in adult rats. 15O water and 18F fluoride PET imaging were used to evaluate blood flow and fluoride kinetics 7 days after loading. 15O water was modeled using a one-compartment, two-parameter model, while a two-compartment, three-parameter model was used to model 18F fluoride. Input functions were created from the heart, and a stochastic search algorithm was implemented to provide initial parameter values in conjunction with a Levenberg-Marquardt optimization algorithm. Results: Loaded limbs are shown to have a 26% increase in blood flow rate, 113% increase in fluoride flow rate, 133% increase in fluoride flux, and 13% increase in fluoride incorporation into bone as compared to non-loaded limbs (p<0.05 for all results). Conclusions: The results shown here are consistent with previous studies, confirming this technique is suitable for evaluating the vascular response and mineral kinetics of osteogenic mechanical loading.
AB - Purpose: Blood flow is an important factor in bone production and repair, but its role in osteogenesis induced by mechanical loading is unknown. Here, we present techniques for evaluating blood flow and fluoride metabolism in a pre-clinical stress fracture model of osteogenesis in rats. Procedures: Bone formation was induced by forelimb compression in adult rats. 15O water and 18F fluoride PET imaging were used to evaluate blood flow and fluoride kinetics 7 days after loading. 15O water was modeled using a one-compartment, two-parameter model, while a two-compartment, three-parameter model was used to model 18F fluoride. Input functions were created from the heart, and a stochastic search algorithm was implemented to provide initial parameter values in conjunction with a Levenberg-Marquardt optimization algorithm. Results: Loaded limbs are shown to have a 26% increase in blood flow rate, 113% increase in fluoride flow rate, 133% increase in fluoride flux, and 13% increase in fluoride incorporation into bone as compared to non-loaded limbs (p<0.05 for all results). Conclusions: The results shown here are consistent with previous studies, confirming this technique is suitable for evaluating the vascular response and mineral kinetics of osteogenic mechanical loading.
KW - Bone blood flow
KW - F fluoride
KW - Mechanical loading
KW - O water
UR - http://www.scopus.com/inward/record.url?scp=84861483063&partnerID=8YFLogxK
U2 - 10.1007/s11307-011-0505-3
DO - 10.1007/s11307-011-0505-3
M3 - Article
C2 - 21785919
AN - SCOPUS:84861483063
SN - 1536-1632
VL - 14
SP - 348
EP - 354
JO - Molecular Imaging and Biology
JF - Molecular Imaging and Biology
IS - 3
ER -