皮肤软组织扩张术对大鼠表皮细胞增殖分化的影响

目的观察皮肤软组织扩张术对大鼠表皮细胞增殖分化的影响。方法36只Wistar大鼠分为干预侧和假手术侧，制作皮肤扩张动物模型，利用表皮干细胞表达角蛋白（keratin 19，K19）、短暂扩充细胞表达K14及增殖细胞核抗原（proliferating cell nuclear antigen。PCNA）的特点，采用免疫组织化学PowerVision^TM二步法检测扩张皮肤表皮干细胞和短暂扩充细胞的分布特征。结果扩张皮肤的表皮层明显增厚，不仅其基底层K19、K14和PCNA阳性细胞的数量明显增多。而且在棘层和颗粒层也可见K19、K14及PCNA阳性细胞的表达。结论皮肤软组织扩张术的应力能诱导大鼠表皮干细胞的增殖与分化，其可能是皮肤软组织扩张术的重要生物学基础。

Effect of skin soft-tissue expansion on proliferation and differentiation of rat epidermal cells

Objective To observe the effect of skin soft-tissue expansion on the proliferation and differentiation of rat epidermal cells.Methods Totally 72 expanders were implanted under superficial fascia on the back of 36 male Wistar rats,two for each rat,one for experiment,one as control.The experimental lateral was performed conventional intermittent skin expansion.Skin samples were collected on day 1,2,3,7 and 10 during expansion process,and post-expansion day 7.Keratin 19,14 and proliferating cell nuclear antigen(PCNA) were employed to determine epidermal stem cells or transient amplifying cells with PowerVision~(TM) two-step immunohistochemical method.Results The expanded epidermis was thicker than control (P<0.01).The number of cells positive for K19,K14 and PCNA in the basal layer of expanded epidermis increased.These positive cells were found scattering within the stratum spinosum and stratum granulosum of the expanded epidermis.Conclusion The stress of skin soft-tissue expansion can induce epidermal stem cells to proliferate and differentiate,which probably is an important biological basis for skin soft-tissue expansion.