[Study on mechanism of the circulation reconstructing of skin flap after early-repeated short ischemia training]

To investigate the effects of repeated short ischemia training on flap survival area, vascular endothelial growth factor and the microvascularsel density.

Seventy-two rabbits were divided into: the experimental group (n=64), the skin flaps were constructed in two sides of back, one side flap were given ischemia training for 15 minutes and 8 times one day at the pedicles from the 1st to 8th day after operation (group A), the other side flap was served as a control (group B), the corresponding site was only marked as a blank control group (group C). Then, 8 pedicles of group A and group B were isolated every day. The surviving area of all skin flaps were calculated on the 5th day after isolating operation. The vascular endothelial growth factor (VEGF) and microvessel density(MVD) of the 3 groups were checked with immunohistologochemical staining.

After the operation, all animals were survival with normal vitality. The survival flap area of group A were significant more than that of group B after 3 days (P<0.05). The expressions of VEGF and MVD of group A and group B were higher than group C. The expression of VEGF of group A was significantly higher than that of group B (P<0.01). The counting of MVD of group A was also significantly higher than that of group B (P<0.05). There was positive correlation between flap survival area and MVD in group A. The relation of time point was n and n-2 respectively,correlation coefficient was 0.850. As well as MVD and VEGF were positive correlation, correlation coefficient was 0.801.

Early repeated short ischemia training can increase flap survival area, the mechanism maybe involve the increased expression of VEGF, which can increased skin flap microvascular density.