EFFECT OF SENSORY NEUROPEPTIDE ON MIGRATION OF EPIDERMAL STEM CELLS IN WOUND REPAIR / 解放军医学杂志

ABSTRACT

Objective To study the effect of neuropeptide on migration of epidermal stem cells in wound repair. Methods 90 new born rats (3～4d old) were randomly divided into three groups SP group, capsaicin group, and normal group. BrdU labeling, combined with specific protein markers of epidermal stem cells, K19 and ?1 integrin, were used to identify epidermal stem cells. The migration of epidermal stem cells was observed in full thickness skin wound on back on 21 days after injury. Substance P was applied to the skin wound after injury in SP group. The status of migration of epidermal stem cells in SP group was compared with that in capsaicin group, in which capsaicin was injected to destroy sensory neuron before skin injury, and with normal group, in which the skin wound was not treated with any medication. Results Wounds of rats in SP group were healed 18 days after injury. It was shortened by three days compared with normal group. Only 25.54% of wound area was healed in capsaicin group on day 18. There were many epidermal stem cells in the edge of the wound and granulation tissue in Group SP. Only a small number of epidermal stem cells were seen in capsaicin group, where SP release was blocked by chemical destruction of sensory neurons, in the wound edge, but not in granulation tissue. The amount of epidermal stem cells as seen in the wound edge, but not in granulation tissue, in normal group was less than in the SP group but more than in capsaicin group. Conclusions SP obviously promotes wound healing and shortens the healing period. SP can induce epidermal stem cells to migrate into the skin wound edge and granulation tissue.