Objective This study aims to explore whether the extracellular signal-regulated kinase(ERK) 1/2 signaling pathway could regulate the osteogenic differentiation of periodontal ligament cells. Methods The human periodontal ligament cells from the third passage were divided into three groups, namely, black control group, osteogenic induction group, and experimental group(10 nmol·L-1PD98059, an inhibitor of ERK1/2 phosphorylation, was added in the osteogenic medium). One or three weeks after culture, the osteogenic capability of the periodontal ligament cells was evaluated using quantitative polymerase chain reaction(qPCR), alkaline phosphatase(ALP) staining, and alizarin red staining. Results Osteogenic induction promoted ERK1/2 phosphorylation. One week after culture, inhibition of ERK1/2 phosphorylation up regulated the expression of Runx2, ALP, and osteocalcin(OCN) in periodontal ligament cells. Statistically significant differences were found in OCN and the osteogenic induction group(PPPPin vitro.
