| Objective: To investigate the effect of natural hirudin combined with flap in rats.Methods: A random skin flap in size of 2.5 cm 10.0 cm was elevated on the dorsum of 72 Sprague-Dawley rats.Then the 72 rats were randomly divided into4 groups(n=18)according to the therapy they received.At immediate and within 4 days after operation,the rats were treated with normal saline injection in control group,normal saline injection combined with hyerbaric oxygen treatment in hyerbaric oxygen group,the natural hirudin injection in natural hirudin group,and the natural hirudin injection combined with hyerbaric oxygen treatment in combined group.The flap survivals were observed after operation,and survival rates were evaluated at 6 days.The skin samples were collected for histological analysis,microvessel density(MVD)measurement,and evaluation of tumor necrosis factor α(TNF-α)expression level by the immunohistochemical staining at 2 and 4 days after operation.Results: Partial necrosis occurred in each group after operation.The survival rate of flap were significantly higher in hyerbaric oxygen group,naturalhirudin group,and combined group than in control group,in combined group than in hyerbaric oxygen group and natural hirudin group(P<0.05).There was no significant difference between hyerbaric oxygen group and natural hirudin group(P>0.05).At 2 days,more microvasculature was observed in hyperbaric oxygen group,natural hirudin group and combined group in comparison with the control group;while plenty of inflammatory cells infiltration was observed in all groups.At 4 days,the hyperbaric oxygen group,natural hirudin group,and the combined group still showed more angiogenesis.Meanwhile,there was still infiltration of inflammatory cells in control group whereas,inflammatory cells in the other groups were significantly reduced compared with at 2 days.At 2days,the MVDs were significantly higher in hyerbaric oxygen group,natural hirudin group,and combined group than in control group(P<0.05);the expressions of TNF-α were significantly lower in hyerbaric oxygen group,natural hirudin group,and combined group than in control group(P<0.05).There was no significant difference in above indexes among hyerbaric oxygen group,natural hirudin group,and combined group(P>0.05).At 4 days,the MVDs were significantly higher in hyerbaric oxygen group,natural hirudin group,and combined group than in control group,in natural hirudin group and combined group than in hyerbaric oxygen group(P<0.05).The expressions of TNF-α were significantly lower in hyerbaric oxygen group,natural hirudin group,and combined group than in control group,in combined group than in natural hirudin group and hyerbaric oxygen group(P<0.05).Conclusion: Hyperbaric oxygen and natural hirudin therapy after random-pattern skin flap transplantation can improve the survival rate.Moreover,combined therapy was seen to exhibit significant synergistic effect on transplanted flap to improve its survival rate.This effect may be related topromotion of angiogenesis and the reduction of inflammation response. |
