两种毛色牦牛皮肤黑色素组织学分析

Melanin Histologic Analysis of Yak Skin in Two Different Colors

【目的】观察两种不同毛色的牦牛皮肤中黑色素分布。【方法】采用冰冻切片和石蜡切片技术,用甲苯胺蓝和HE染色进行组织学分析。【结果】两种切片方法均能展现毛囊结构、皮肤组织分层结构。甲苯胺蓝染色:石蜡切片比冰冻切片着色较浅,易观察到黑色素的分布;冰冻切片通过显微镜观察发现牦牛毛囊由毛鞘、毛乳头和毛球外围的结缔组织形成。HE染色:冰冻切片着色较深,皮肤结构层次分明;石蜡切片着色均匀,细胞分布明显。【结论】天祝白牦牛表皮的基底层和毛囊周围发现分布着少量的黑色素。大通牦牛的毛囊和表皮中均发现有大量黑色素的存在。大通牦牛毛囊中与毛发相连毛乳头附近的黑色素含量比毛囊周围其他部位含量高,皮肤表皮基底层相对毛囊黑色素含量少。大通牦牛毛囊周围黑色素比天祝白牦牛密集,且更为明显。大通牦牛的毛囊群比天祝牦牛毛囊群密集,毛囊的直径比天祝牦牛的长,毛发较粗。石蜡切片的HE染色是比较好的方法。

【Objective】To study the melanin distribution in two different coat colors of yak skin.【Methods】The experiment used frozen section and paraffin section technique,Toluidine blue and HE dye wereused to histologic analysis.【Results】Two kinds of slice methods could show the hair follicle structure,stratification of the skin tissue structure.Toluidine blue staining:paraffin had shallower color thanfrozen,and easier for observing the distribution of melanin;frozen section showed that yak hair folliclewas made up of wool sheath,hair papilla and the bulb outside the surrounding connective tissueformation through microscope.HE staining:frozen section was deeper colored,and had distinct skinstructure;paraffin section colored uniformly,and cell distributed obviously.【Conclusions】A smallamount of melanin was found in Tianzhu's skin and hair follicles and a large amount of melanin wasfound in Datong's skin and hair follicles.The hair dermal papilla near the melanin content in Datongyak hair follicles was higher than other parts around the hair follicles,and skin epidermal basal layerrelatively less hair melanin content.Hair follicle melanocytes of Datong yak was denser than Tianzhuyak,and more obvious.Datong yak hair follicle group was denser,the diameter of the hair follicle was longer than Tianzhu and with thicker hair.Paraffin section with HE staining was a better method.