Intellectual and scientific content of the study, surgical procedures, critical revision. ABSTRACT PURPOSE:To evaluate the potential of heterologous platelet-rich plasma (PRP) gel for surgical skin wound healing in rabbits METHODS: Blood from a single healthy dog was used for PRP production, with calcium gluconate added to the PRP to form the gel.Two surgical excisions, one to the right and the other to the left of the dorsal midline, were made in six rabbits. One side was randomly allocated to topical application of a physiological solution, and the other was allocated to treatment with heterologous PRP gel. Clinical assessments (weight, pain sensitivity, coloring, edema, hyperemia, exudation, crust, and granulation) and morphometric evaluations were performed 0, 3, 7, 10, 14, and 17 days postoperatively. Histological analysis was performed on the 17 th day. RESULTS:With the exception of the presence of a crust at day 10, clinical variables did not differ significantly between the experimental groups. In both the control and PRP-treated groups, differences were identified when comparing time-points in terms of wound area reduction. Histological results indicated no significant differences between the control group and the PRP-treated group. CONCLUSION:Heterologous platelet-rich plasma gel promoted dermal wound healing in rabbits with no adverse effects.

Over the years, autologous platelet-rich plasma (PRP) has been used to great advantage in the healing of acute and chronic wounds. However, it is impossible to use in some situations so alternative PRPs need to be considered, such as homologous or heterologous PRPs. In order to evaluate the effects of PRP in the form of autologous, heterologous and homologous gels on in vivo cutaneous wound healing, 18 animals divided into three groups of six, were used for the study, with another six animals used as PRP donors. For the heterologous group an adult, mixed breed dog was used to obtain the PRP. The wounds were induced using an 8 mm punch. The left side was treated with NaCl 0.9%® (A) and a PRP gel was applied (GA = autologous; GHE = heterologous and GHO = homologous) on the right side (B). The wounds were evaluated for a period of 17 days. On the 17th day biopsies were taken for histopathological assessment of the wounds. The percentage of contraction was evident in side B (treated), which was confirmed in the microscopic analysis of the histological sections. Thus, it was concluded that PRP, regardless of the source, improves and accelerates the healing process, demonstrating its therapeutic potential on cutaneous lesions and its use in patients with impaired wound healing.

Recent studies have been carried out to evaluate the role of platelet-rich plasma (PRP) in the cicatrization of wounds; however, the protocols for treatment have been based on a single application of PRP.To evaluate the effect of autologous platelet-rich plasma in gel form on the cicatrization of cutaneous wounds in vivo experimental model, wounds were induced in the dorsal areas of six New Zealand white rabbits with the aid of an 8-mm punch. The right side was used as a control (A) and treated with 0.9% NaCl, whereas the left side (B) was treated serially with the autologous platelet-rich plasma gel. Lesions were assessed over a 17-day period. At days 0, 10 and 17, the animals were evaluated and morphological and morphometric analyses of the wounds were performed. At day 17, a biopsy was performed for histopathological evaluation. Macroscopically, wounds treated with PRP showed better cicatrization and higher contraction percentages than the control wounds. Regarding the percentage of wound contraction, it was found that the average treated wound with autologous platelet-rich plasma gelwas 95% while withthecontrolwas88%. We concluded that autologous platelet-rich plasma gel is effective and accelerates cicatrization when used serially in short intervals, thus confirming its therapeutic potential in cutaneous lesions and potential as an alternative wound treatment option. Key words: Autologous platelet-rich plasma. Rabbit. Skin regeneration. Wounds. ResumoEstudos recentes demonstram uma evolução do papel do plasma rico em plaquetas (PRP) na cicatrização de feridas. No entanto, os protocolos para tratamento baseiam-se em uma única aplicação do PRP. Para avaliar o efeito da aplicação seriada do plasma rico em plaquetas autólogo na forma gel sobre a cicatrização de feridas cutâneas em modelos experimentais in vivo, induziu-se feridas no dorso de seis coelhos brancos da raça Nova Zelândia com auxílio de um punch de 8mm. O lado direito foi considerado controle (A) e tratado com NaCl 0,9% e o lado esquerdo (B)e tratado com gel autólogo de plasma rico em plaquetas. As lesões foram avaliadas por um período de 17 dias. Nos dias 0, 10 e 17, as feridas foram avaliadas morfológica e morfometricamente. No 17º dia foi feita biópsia para avaliação histopatológica. Macroscopicamente, as feridas tratadas com PRP evidenciaram melhor cicatrização e maior porcentagem de contração quando comparadas as feridas controle. Com relação ao percentual de contração das feridas, verificou-se que a média das feridas tratadas com plasma rico em plaquetas autólogo gel foi de 95%, enquanto o lado controle foi de 88%. Concluiu-se que o PRP autólogo gel é eficaz e acelera o processo de cicatrização, quando aplicado em intervalos curtos e de forma seriada, comprovando seu potencial terapêutico sobre lesões cutâneas, podendo ainda ser uma alternativa de tratamento de feridas. Palavras-chave: Cicatrização. Coelhos. Feridas. Plasma rico em plaquetas autólogo.