OBJECTIVETo explore the relationship between neuropeptide substance P (SP) and wound healing in scalded rats.

METHODS(1) Scalded rats with different degrees of scald injury were employed as the experimental model and were sacrificed at 24 post scald hour (PSH), and on 3, 7 and 14 post scald days (PSD). The SP content in the wound was detected with radioimmunoassay method. (2) The murine granulation tissue fibroblasts (GTF) were cultured with different culture media, and divided into control, SP and Spantide (SP receptor antagonism) groups. The effects of SP and Spantide on the cellular activity and apoptotic rate of murine GTF were assessed in vitro.

RESULTSThere was significant difference of the SP content among the superficial (145 +/- 78) ng/g, partial (94 +/- 48 ng/g) and full thickness (53 +/- 27 ng/g) scald wounds at 24 PSH (P < 0.01), while the SP content in partial thickness burn wound on 3 and 7 PSD obviously increased; and that in deep partial thickness burn wound obviously increased on 7 and 14 PSD. But the SP content remained unchanged in full thickness scald wound. (2) SP could promote the activity of GTF and inhibit its apoptosis (The GTF activity in control, SP groups were 0.21 +/- 0.05, 0.36 +/- 0.07, respectively, P < 0.01). Spantide could inhibit the interaction between SP and GTF.

CONCLUSIONSP can promote GTF proliferation, and the SP content in wound is closely associated with the depth of the injury and wound healing capacity.