OBJECTIVETo investigate the influence of the prostaglandin E2 on the proliferation of the melanocytes in the full-thickness skin graft.

METHODSSixty-eight guinea-pigs were divided into experimental-1 group (skin graft), experimental-2 group (skin graft + diclofenac), and control groups. After the full-thickness skin graft, the dynamic changes of the prostaglandin E2 were measured and the proliferation of the melanocyte with its density was also evaluated by using histochemical and autoradiographic methods.

RESULTSIn the experimental-1 group, the content of PGE2 was increasing in seven days after the operation, continued to the one month, and then returned to the base level. The labelling indices of 3H-MC-TdR of the group was also increasing postoperatively between the second day and the fourteenth day, and reach a second peak after one month, then came to the normal level. The density of the melanocytes was decreasing rapidly 3 days after the surgery, then began to increase and exceeded over the normal level 21 days after the operation. However, in the experimental-2 group, the content of PGE2 decreased in two days after the surgery, and then showed the inclination similar to the experimental-1 group with the different points in narrower range. The number of melanocytes labelled by 3H-TdR began to increase at the first day after the surgery, which appeared earlier than the experimental-1 group and was similar in the changing tendency with a less extent. The density of MC showed the similar tendency to the experimental-1 group in a narrower changing range with both of increasing and decreasing. The density of the MC was much lower in 21 after the operation than the experimental-1 group and normal control group.

CONCLUSIONThe increased PGE2 in the earlier stage of the skin grafting could enhance the inflammatory reaction to the tissue, as well as the melanocytes. It may stimulate the proliferation of the MC with the result of increasing their density. The use of the diclofenac might reduce the inflammation and suppress the proliferation of melanocytes, and result in the skin with light color due to decreasing the number of MC in the epidermis of the graft.