[Effect of hirudin on random skin flap survival in rats].

Objective: To investigate the effect of Hirudin on random skin flap survival in rats.

Methods: 24 SD rats were randomly divided into control group and experimental group. The "McFarlane flap (3 cm x 9 cm)" rat models were established on the rat dorsum. 3 ml Hirudin (30 ATU) was injected into the flap in the experimental group, while 3 ml saline in the control group. The injection was performed for 7 days. The flap survival area in the two groups was measured. The tissue samples were taken from proximal (I), middle (II) and distal (III) portions of flaps for histologic study. The VEGF and bFGF expression was also detected with immunohistochemistry method.

Results: 7 days after operation, the flap survival rate was (69.52 +/- 3.23)% in the experimental group, while (50.36 +/- 2.37)% in control group, showing a significant difference between the two groups (P < 0. 01). In the middle portion, tissue edema and infiltration of neutrophils in experimental group was markedly slighter than that in control group. The VEGF and bFGF expression and neovascularization was enhanced markedly in experimental group.

Conclusions: Hirudin can increase the survival of random pattern skin flaps. It may increase the VEGF, bFGF expression through a series of complex regulatory pathway. Then flap neovascularization is promoted and the flap blood supply is increased.