OBJECTIVETo study the effects of VAC on starting the process of wound healing and decreasing apoptosis.

METHODSTo examine the variations in expression of proto-oncogenes c-myc, c-jun and Bcl-2 in pig wound model with acute full-thickness skin defect and human chronic wounds by immunohistochemistry, calculate the numbers of expressive positive cells and the labelling index (LI), and observe the process of wound healing.

RESULTS(1) In pig experiment, the wound in experimental group was very clean and without obvious exudates, many neoepiderm and granulation tissue rapidly appeared or formed after 6 days, and healed completely by the 25th day. On the contrary, in the wound of control group, more exudates and blood crust could be seen and fewer neoepiderm and granulation tissue appeared after 6 days and was healed by 30th day. Immediately after the wound was created, the expression of c-myc, c-jun and Bcl-2 was lower and mainly situated in nucleus or cytoplasma of the basilar cells. After the wound was created in control group, or after starting the VAC treatment in experimental group, their expression rapidly and obviously increased, the distribution of the positive cells also became enlarged, but the amount of expression decreased rapidly after the expressive peak have reached. In the successive 12 days following the wound was created, the expression of c-myc, c-jun and Bcl-2 in the experimental group was constantly higher than that of the control group. (2) In human chronic wounds, there wasn't obvious secretions and more healthy granulation tissue was rapidly formed after VAC treatment. The expression of c-jun was mainly located in cytoplasma of basilar cells of epithelium, dermal fibroblasts and inflammatory cells, and the positive cell and labelling index obviously decreased. The expression of c-myc and Bcl-2 was mainly in cytoplasma of basilar cells, but the amount of expression and the labelling index became obviously increased after VAC treatment.

CONCLUSIONSVAC could rapidly start the healing course of the pig' s acute skin wound and human chronic wound, decrease apoptosis of the reparative cells, so as to accelerate wound healing.