刺鼠信号蛋白对自体移植皮片中黑素细胞功能的影响

Influence of agouti signal protein on melanocyte function in skin autograft

目的:通过检测刺鼠信号蛋白对自体移植皮片中黑素细胞功能的影响,进一步认识自体移植皮片过度色素沉着的原因。方法:建立过度色素沉着的自体移植皮片动物模型,皮片下分别注射刺鼠信号蛋白和生理盐水(对照组)。利用RT-PCR方法检测刺鼠信号蛋白作用后自体移植皮片(n=12)黑素细胞中酪氨酸酶mRNA的表达,银染-丽春红染色后检测皮片中黑色素的含量,并与对照组(n=13)及正常豚鼠皮肤(n=5)相比较。结果:经刺鼠信号蛋白作用后,皮片中酪氨酸酶mRNA表达和黑素含量均明显减少,与对照组皮片和正常豚鼠皮肤相比其差异具有显著性意义(P<0.01)。结论:刺鼠信号蛋白在自体移植皮片中,能竞争性拮抗α-黑素细胞刺激素的黑素合成作用,使皮片着色能力降低。进一步证明了皮片移植后表皮细胞中α-黑素细胞刺激素的表达上调是皮片呈过度色素沉着的重要原因。

Objective：To study the influence of agouti signal protein （ASIP） on melanocyte function in skin autograft, so as to understand the cause of hyperpigmentation in skin autograft. Methods： Guinea pigs were used to establish a skin autograft hyperpigmentation model. The skin autografts in model animals were injected with ASIP or normal saline （control）. RT-PCR technique was used to detect the tyrosinase mRNA expression in melanocytes of skin autografts and Masson-Fontana staining technique was used to detect the melanin contents in skin autografts in ASIP treatment group; and the results were compared with those of control group （n= 13） and normal guinea pigs （n= 5）. Results： The expression of tyrosinase mRNA and the melanin content in skin autografts in ASIP treatment group were both lower than those of control group and normal guinea pigs （P〈 0.01）. Conclusion： The results indicate that ASIP can antagonize the melanogenic effect of α-MSH, resulting in reduced pigmentation in skin autografts. It is also indicated that overexpression of α-MSH in epidermal cells after skin grafting is an important cause of hyperpigmentation in skin autografts.