EDN3在不同毛色小鼠皮肤中的表达与定位

内皮素3（endothelin 3, EDN3）对早期黑色素细胞的迁移及增殖分化有促进作用，并可通过与其受体结合促进黑色素的合成。EDN3在不同毛色小鼠皮肤中的差异及其在毛色形成过程中的作用仍有待研究。实时荧光定量PCR结果显示，灰色小鼠皮肤中EDN3的表达量显著高于黑色及棕色小鼠，约为其2倍(P<0.01)。蛋白免疫印迹结果显示，灰色小鼠皮肤内EDN3的含量为黑色小鼠的5倍，棕色小鼠为黑色小鼠的2倍。ELISA结果表明，灰色小鼠皮肤中EDN3的蛋白质表达量分别是黑色和棕色小鼠的1.8倍和1.4倍(P<0.01)。免疫组织化学显示，EDN3在毛囊的毛基质及内外毛根鞘有明显表达，毛乳头等部位有少量表达。EDN3在不同毛色小鼠皮肤中的表达存在显著差异，是维持黑色素细胞存在不可缺少的因子，可能对两种色素颗粒的相互转化有一定的作用。

Localization and Expression of EDN3 in Mouse Skin with Different Coat Colors

Endothelin 3 (END3) binds to its receptor to promote the migration, proliferation and differentiation of early melanocyte, also boosts the synthesis of melanin. The diversity of END3 among different coat color mice and the effects of END3 on the formation of coat color need to be investigated. The real-time quantitative PCR result showed that EDN3 expression in gray mouse skin was significantly higher about 2 folds (P< 0.01) than those from black and brown mice; whereas in EDN3 Western blotting, the fold difference was 5, or 2 between brown and black mice (P< 0.01). The ELISA result indicated that EDN3 protein levels in gray mice was 1.8 times higher than in black mice, or 1.4 times than in brown mice (P< 0.01). Immunohistochemistry showed that the EDN3 was predominantly expressed in the matrix, outer root sheath, but weak in dermal papilla of hair follicular. The results indicated that END3 was an essential factor in melanocytes, which played a role in the conversion between two types of pigment particles.