Effects Of L-Arginine Applied In Distraction Osteogenesis On Rabbit Mandibulars

ObjectiveThe purpose of this paper was to observe the effects of L- Arginine applied in Distraction Osteogenesis on rabbit mandibulars and to explore mechanism of them,in order to provide new way to shortened teatment of DO.Methods32 rabbits, weighing 2.0±0.25kg, adapted for 1 week, were randomly assigned into control and L-Arg group, each group comprising 16. All rabbits underwent unilateral mandibular distraction osteogenesis. After surgeries, L-Arg group was fed L-Arg 1.1g in water every day and control group was fed ordinary water. Four days later ,all rabbits were distracted for 4 days, 0.5 mm per time and twice a day. They were sacrificed at 1, 7,14 and 28 days after DO .The new generated bone were detected by X-ray , histological examination and immunohistochemistry. Blood was drawn before scarification to test nitrite concentration in serum.The induced NOS (iNOS) and endothelial NOS (eNOS) were determined in the average optical density. All data was statisticed by the independent sample t test of SPSS.ResultsAll animals were no infection or rejection after surgery. X-ray and histological show the density increased and new bone formation constantly in the distraction gaps. New bone formation and mineralization was faster in L-Arg group.Serum concentration of NO was stable in L-Arg group ,and it fluctuate from the top down to bottom in control group. Histological found angiogenesis, proliferation and calcification of bone cell was earlier in L-Arg group. The expression of iNOS was more intense in the control group over the same period, and the expression of eNOS was higher but stable in L-Arg group. ConclusionsL-Arg could promote the new bone formation. L-Arg , catalyzed by NOS ,could release NO.NO could activate osteoblasts, inhibit osteoclast function, increase blood supply and coordinate relative factors to accelerate formation and mineralization of new bone.So it can reduce treatment of Distraction Osteogenesis.