Abstract: Objective To investigate the levels of serum IGF-Ⅰ and PDGF and the role they played in healing of femoral fracture complicating cerebral trauma.Methods One hundred and fifty-two rats were divided into four groups randomly.They were group A,negative control;group B,cerebral traumas;group C,fracture of femur;and group D fracture of femur complicating cerebral trauma.Rat models with femoral fracture and cerebral trauma were established and blood serum collected at day 1,4,week 1,2,3 and 4 after the operations.The levels of IGF-Ⅰ and PDGF were detected by ELISA method.Results The concentrations of IGF-Ⅰ in group C had not changed significantly.The IGF-Ⅰ in group B and D changed more significantly(P<0.01).They increased positively in the first day and the maximum value was detected after four days,and decreased gradually in two weeks,however still much higher than those in groups A and C(P<0.01).After four weeks,the levels in groups B and D declined to that in group A and there was no statistical difference among those four groups then.At the first day,the PDGF levels in group B,C and D were lower than that in group A(P<0.01).Two weeks later,the PDGF levels in groups B and group C decreased to the same level as that in group A.However,there was statistical difference between group D and the other three groups(P<0.01).Conclusion The levels of IGF-Ⅰ and PDGF in serum may be involved in the fast healing process of femoral fracture complicating cerebral trauma,and there may be a synergetic relationship between IGF-Ⅰ and PDGF.

Key words: cerebral trauma, union of fracture, IGF-Ⅰ, PDGF, ELISA