牛蛙皮肤显微结构与组织化学研究

Investigation on microstructure and histochemistry of bullfrog skin

运用HE染色和3种组织化学方法—改良甲苯胺蓝、阿利新蓝-PAS和多巴氧化酶法染色对牛蛙皮肤显微结构和特性进行了研究。结果表明,牛蛙皮肤由表皮和真皮组成,表皮由角质层、颗粒层和生发层组成,表皮内无黑色素分布,微血管较少。真皮比表皮厚,分为疏松层和致密层。真皮疏松层内有大量团块状、致密的黑色素,微血管较多。真皮疏松层中分布着黏液腺和颗粒腺,黏液腺多于颗粒腺。牛蛙皮肤肥大细胞主要分布于真皮疏松层和皮下层,且多为长条形。真皮致密层呈阿利新蓝-PAS染色强阳性,表皮与真皮交界处以及真皮疏松层和致密层交界处也有强阳性带。多巴氧化酶法染色结果表明,无黑色素分布的表皮层有许多弥散、细小的阳性棕黑色颗粒状色素,而有大块天然黑色素分布的真皮疏松层阳性颗粒色素较少。结果提示,牛蛙皮肤可通过腺体、肥大细胞和黑色素发挥重要的免疫防御和保护作用。

Microstructure and histochemical property of the bullfrog skin(Rana catesbeiana)was studied by using HE staining and three histochemical staining methods,including toluidine blue,alcian blue– PAS and dopa oxidase staining.The results showed that the skin was consisted of epidermis and dermis.The epidermis was made of stratum corneum,stratum granulosum and stratum germinativum.There were no melanin and a few capillaries in the epidermis.The dermis was thicker than the epidermis and was made of stratum spongiosum and stratum compactum.The stratum spongiosum contained a large number of massive and thick melanin.Numerous microvessel,mucous glands and granular glands in stratum spongiosum,and the mucous glands were more plentiful than granular glands.Many mast cells were in the skin of bullfrog,most of which were slim and mainly inhabited in stratum spongiosum and hypodermis.The stratum compactum of the dermis was strongly positive by alcian blue– PAS staining.The junctures of the epidermis and dermis,stratum spongiosum and stratum compactum of dermis were also positive.The results of dopa oxidase staining demonstrated that there were numerous diffuse,granular and small positive brown pigment in the epidermis without nature melanin.There were a few positive!particles with black nature melanin in the stratum spongiosum.The results suggest that skin of bullfrog can play an important role in the immune prevention and protection through the glands,mast cells and melanin.