Liang Zhi, Xie Cheng-yu, Lin Hai-bo, Guo Zheng-dong, Yang Wei-guo
Department of Burns and Plastic Surgery, The Sixth People's Hospital, Shenzhen 518052, PR China.
Zhonghua Shao Shang Za Zhi. 2006 Feb;22(1):29-32.
To further explore the relationship between hypertrophic scar and injury to conical structure of skin and the pathogenesis of hypertrophic scar, and to reproduce an optimal animal model of hypertrophic scar.
The back of two FRDP pigs were shaved, and a piece of normal skin was harvested for the observation of conical structure of skin. Skin wounds with depth of 0.38 mm, 0.76 mm, 1.14 mm and 1.52 mm, respectively, were created by gas-driven dermatome. Eight wounds measuring 7.0 cm x 7.0 cm were created on each pig. The wounds were divided into 4 groups according to the wound depth with 4 wounds in each group, i.e. 0.38 mm group, 0.76 mm group, 1.14 mm group and 1.52 mm group. The 0.38 mm and 0.76 mm groups were designated as superficial wound groups and 1.14 mm and 1.52 mm groups as deep wound groups. The wounds were allowed to heal without treatment. Tissue samples from the wound were harvested on 0, 10, 30, 60, 90 and 150 post injury day (PID) , and they were sectioned for HE staining and staining for elastic fibers (VVG). The wound healing and the scar formation were observed with naked eye. The skin conical structures in normal and injured skin were also observed. The morphology of hypertrophic scar was observed, and the thickness of the scar tissue was determined and scored.
The wounds in superficial wound groups healed within 3 weeks with flat surface without scar formation. The wounds in deep wound groups healed later than 4 weeks with thick, hairless, hard in texture, with depigmentation or pigmentation, finally forming contracture. The skin conical structure could be found on the back of FRDP with HE and VVG staining, and it was similar to that of human in terms of the structure. In superficial wound groups, the upper part of the skin conical structure was injured, but fat fornix and glands were intact. In deep wound groups, the lower part of the skin cone, together with the fat fornix and gland were all injured. On the 150th post injury day, the histological picture of the tissue in superficial wound groups was similar to that of normal skin. But the skin conical structure could not be found in deep wound groups, and the wounds were filled by a large accumulation of disarrayed and irregularly arranged collagen fibers. With passage of time, the scar became thicker and thicker, and the scar hypertrophy reached the zenith in 150th PID.
The injury of skin conical structure can lead to the formation of hypertrophic scar. FRDP can be used to reproduce and ideal model of hypertrophic scar.
为进一步探讨增生性瘢痕与皮肤圆锥结构损伤的关系及增生性瘢痕的发病机制，并建立理想的增生性瘢痕动物模型。
将两头巴马小型猪背部毛发剃净，取一块正常皮肤观察皮肤圆锥结构。用气动式取皮刀分别制作深度为0.38mm、0.76mm、1.14mm和1.52mm的皮肤创面。每头猪制作8个7.0cm×7.0cm的创面。创面按深度分为4组，每组4个创面，即0.38mm组、0.76mm组、1.14mm组和1.52mm组。将0.38mm和0.76mm组定为浅创面组，1.14mm和1.52mm组定为深创面组。创面不予处理任其愈合。于伤后0、10、30、60、90和150天（PID）取创面组织样本，进行切片，行HE染色及弹性纤维（VVG）染色。肉眼观察创面愈合及瘢痕形成情况。观察正常及损伤皮肤的皮肤圆锥结构。观察增生性瘢痕的形态，测定瘢痕组织厚度并评分。
浅创面组创面3周内愈合，表面平整，无瘢痕形成。深创面组创面愈合时间超过4周，愈合后瘢痕厚，无毛发生长，质地硬，有色素脱失或色素沉着，最终形成挛缩。通过HE和VVG染色可在巴马小型猪背部发现皮肤圆锥结构，其结构与人相似。浅创面组皮肤圆锥结构上部受损，但脂肪穹窿和腺体完整。深创面组皮肤圆锥下部连同脂肪穹窿和腺体均受损。伤后150天，浅创面组组织学图像与正常皮肤相似。但深创面组未发现皮肤圆锥结构，创面被大量排列紊乱、不规则的胶原纤维充填。随着时间推移，瘢痕逐渐增厚，伤后150天瘢痕增生达到高峰。
皮肤圆锥结构损伤可导致增生性瘢痕形成。巴马小型猪可用于建立理想的增生性瘢痕模型。
