Objective:To establish a full-thickness skin defect wound model on rabbit dorsum and to observe the effects of platelet-rich plasma (PRP) with varying injection frequencies on wound healing.Methods:Forty New Zealand white rabbits were used, with two symmetrical 4.0 cm diameter circular full-thickness skin defects created along the spinal axis on each rabbit′s back, yielding 80 wounds. These wounds were randomly divided into 8 groups (4 experimental and 4 control groups, 10 wounds per group) using a random number table. Experimental group 1 and control group 1 received a single injection of autologous PRP or normal saline at the time of wound creation. Experimental group 2 and control group 2 received two injections at the time of wound creation and on day 5. Experimental group 3 and control group 3 received three injections at the time of wound creation and on day 5, day 10. Experimental group 4 and control group 4 received four injections at the time of wound creation and on day 5, day 10, day 15. Photographic documentation was performed on postoperative day 5, day 10, day 15 and day 20 to evaluate healing progression and calculate wound healing rates. Tissue samples harvested on day 20 underwent hematoxylin-eosin (HE) staining, Masson staining, and immunohistochemical staining to measure microvessel density.Results:The wound healing rate of each experimental group was higher than that of each control group. With the increase in the number of PRP injections, the wound healing rate became faster and the wound was closer to normal skin. The wound healing rates of the experimental group 3 and the experimental group 4 were higher than those of the experimental group 2, the experimental group 1, and the four control groups (all P<0.05). However, there was no statistically significant difference in the wound healing rate between the experimental group 3 and the experimental group 4 ( P>0.05). The results of HE staining indicated that with the increase in the number of PRP injections, there was less infiltration of inflammatory cells and more newly formed capillaries. The results of Masson staining suggested that as the number of PRP injections increased, the arrangement of collagen fibers became more regular. The results of immunohistochemical staining showed that the microvessel density of the four experimental groups was greater than that of the four control groups (all P<0.05). Conclusions:PRP injection enhances wound healing rates. Multiple PRP injections yield superior therapeutic outcomes compared to a single administration.

Objective:To establish a full-thickness skin defect wound model on rabbit dorsum and to observe the effects of platelet-rich plasma (PRP) with varying injection frequencies on wound healing.Methods:Forty New Zealand white rabbits were used, with two symmetrical 4.0 cm diameter circular full-thickness skin defects created along the spinal axis on each rabbit′s back, yielding 80 wounds. These wounds were randomly divided into 8 groups (4 experimental and 4 control groups, 10 wounds per group) using a random number table. Experimental group 1 and control group 1 received a single injection of autologous PRP or normal saline at the time of wound creation. Experimental group 2 and control group 2 received two injections at the time of wound creation and on day 5. Experimental group 3 and control group 3 received three injections at the time of wound creation and on day 5, day 10. Experimental group 4 and control group 4 received four injections at the time of wound creation and on day 5, day 10, day 15. Photographic documentation was performed on postoperative day 5, day 10, day 15 and day 20 to evaluate healing progression and calculate wound healing rates. Tissue samples harvested on day 20 underwent hematoxylin-eosin (HE) staining, Masson staining, and immunohistochemical staining to measure microvessel density.Results:The wound healing rate of each experimental group was higher than that of each control group. With the increase in the number of PRP injections, the wound healing rate became faster and the wound was closer to normal skin. The wound healing rates of the experimental group 3 and the experimental group 4 were higher than those of the experimental group 2, the experimental group 1, and the four control groups (all P<0.05). However, there was no statistically significant difference in the wound healing rate between the experimental group 3 and the experimental group 4 ( P>0.05). The results of HE staining indicated that with the increase in the number of PRP injections, there was less infiltration of inflammatory cells and more newly formed capillaries. The results of Masson staining suggested that as the number of PRP injections increased, the arrangement of collagen fibers became more regular. The results of immunohistochemical staining showed that the microvessel density of the four experimental groups was greater than that of the four control groups (all P<0.05). Conclusions:PRP injection enhances wound healing rates. Multiple PRP injections yield superior therapeutic outcomes compared to a single administration.