Effect Of Postoperative PRP Injection In Promoting The Survival Of Narrow Pedicle Skin Flap In SD Rats

Objective To investigate the effect of immediately postoperative PRP injection on the survival of narrow and narrow pedicled flap in SD rats.Methods 36 male SD rats were randomly divided into PRP group,PPP group and control group.6ml of blood was collected from each group of rats,and the platelet count was measured,The blood samples of PRP group and PPP group were prepared by Landersberg method,and the products were analyzed again.The animal model of the narrow pedicle skin flap was established in the back of rats.After the skin flap was transplanted in situ,PRP was injected into the skin flap of PRP group,PPP group was injected with PPP of the same volume,and rats in the control group were injected with calcium chloride solution of the same volume,Immediately,one day,three days,five days and seven days after the operation,the distal part of the flap was cut and divided into two parts.One part was stained for analysis of HE staining,CD34 and TGF-βR immunohistochemistry,the other was stored in a refrigerator at-80℃ and measured by ELISA.The survival rate of the flap was calculated 7 days after the operation.The MVD and TGF-β R in the flap were analyzed semi quantitatively at different times.All rats were killed 7 days after the operation.The concentration of TGF-β1and VEGF in the whole blood of the rats in each group was measured by ELISA.The data were analyzed statistically.Results There was no significant difference in platelet count among the three groups(F=1.032,P>0.05).Before and after PRP and PPP preparation,the platelet count in blood samples was tested by paired t test(t=282.56,t=38.84,P<0.05).The survival rates of the flaps were(86.67±2.80)%,(72 ± 3.10)%,(64.17±3.79)%,(61.75 ± 2.60)%,respectively The difference was significant(F=234.70,P<0.05).MVD value,CD34 and TGF-βr quantitative analysis showed that in the three groups of flaps,the three showed a trend of first increasing to the peak value and then falling back.TGF-βr reached the peak value 3d after operation,and CD34 and MVD value reached the peak value of 5d.Compared with PPP and control group,MVD,TGF-β R and CD34 were significantly higher in PRP group at different time points,the difference was significant,and there was no significant difference between PPP group and control group.The expression of TGF-β1and VEGF in 7 days after operation was significantly different in PRP group,and there was no significant difference between the other two groups.Conclusion PRP Injection can promote the expression of TGF-β and VEGF,induce angiogenesis,accelerate wound healing,and promote the survival of narrow pedicle skin flap.