ABSTRACT
Objective To investigate the accelerating role of recombinant human parathyroid hormone (PTH) in bone fracture repair.Methods 2-month old male Sprague-Dawley rats underwent closed unilateral femoral fracture and intramedullary nail fixation.The rats were divided into 2 equal groups randomly: the treatment group receiving subcutaneous injection of rhPTH(1-34) 10 μg/(kg·d) immediately after operation and for 2,7,14,21 and 42 d,respectively, and the control group receiving subcutaneous injection of normal saline in the same volume.X-ray and micro-CT were conducted at 2, 7, 14, 21 and 42 days after surgery.Results The continuity of porosis between fracture sides was better and fracture line has been blurred in the PTH-treated group at 21 days after fracture compared with the control group, the bone volume (BV),BV/TV, bone mineral density(BMD)and trabecular pattern factor (Tb.Pf) were significantly higher, and trabecular separation (Tb.Sp) and degree of anisotropy (DA) were significantly lower in the PTH-treated group at 42 days after fracture.Conclusions Our findings suggest that a low dose recombinant human parathyroid hormone can accelerate the bone fracture healing, probably through improving the BV, BV/TV, Tb.P and BMD, and decreasing the Tb.Sp and DA.
ABSTRACT
Objective To evaluate the possible mechanism of traumatic brain injury (TB1) affecting the speed of bone fracture healing.Method TBI combined with unilateral tibial fracture (group A) was used to build multiple injury model and simple unilateral tibial fracture (group B),and the FOS,JUN,bFGF,and VEGF protein expression in different time points between the two groups were compared,and roentgenogram was used for the evaluation of bone healing.Results The expression of FOS,JUN,bFGF,and VEGF protein of the cerebral tissue was low in the normal rats,but was slightly enhanced in group B.There was consistence of development for FOS and JUN expression in the brain tissue in group A,reaching peak at post-TBI 3 hours,and then reducing to control level after 12 hours.The bFGF and VEGF reached peak at post-TBI 12 hours and 24 hours and reduced to control level after 72 hours,respectively.In group A and group B,an increase in the FOS,JUN protein expression around the fracture site was observed at 3 hours after injury,which reached the peak at 6 hours,and reduced to the control level after 24 hours;the comparison between group A,group B and the control group at 3 hours,6 hours and 12 hours had significant difference (P