Abstract:

Objective　To investigate the spatial and temporal expression changes of fibronectin and integrinβ1 mRNA during fracture healing.Methods　Using in situ RT-PCR technique, the spatial and temporal expression pattern of both fibronectin and integrinβ1 mRNAwas detected on paraffined slices in different rabbit mandibular fracture healing phases.Results　①The mRNA of integrinβ1 and fibronectin was widely expressed in fractured bone cells. The positive stain existed in cytoplasm and nucleolus. ②After 7 days of fracture, increaseded integrinβ1 mRNA expression was observed, and it reached maximal levels approximately 14~30 days post-fracture and returned to normal levels after 60~90 days.③Fibronectin mRNA was detected on 3 days post- fracture, it reached maximal levels at 7~14 days,faint expressionwas detected at 30 days, undetectable 60 days afterwards.Con- clusion　During fracture healing, the mRNA expression of integrinβ1 and fibronectin increased locally, FN and Itgβ1 cooperate with each other,it is suggested that they have an important influence on fracture healing.

Key words: integrinβ1, fibronectin, fracture healing, in situ RT-PCR