Effect of polyethylene particles on the expression of RANKL, RANK and OPG in bone calvariae. Quantitative real-time PCR analysis were performed 24 hours after calvariae culture (n = 5 per group). For every sample, experiments were carried out in triplicate and results are presented as mean ± standard error of the mean. a indicates P < 0.05, compared to sham-implanted internal controls. OPG, osteoprotegerin; RANK, receptor activator of the nuclear factor κB; RANKL, RANK ligand.
Nich et al. Arthritis Research & Therapy 2011 13:R100 doi:10.1186/ar3381