豫医无毛小鼠皮肤透射电镜观察

Observation on the Dorsal Skin in YYHL by Electron Microscopy

采用透射电镜技术对12～28日龄豫医无毛小鼠(YYHL)背部皮肤超微结构进行了观察。结果发现:12日龄时,无毛小鼠皮肤毛囊上皮细胞簇集成团,占据毛球的位置;14日龄时,毛囊上皮细胞出现不同程度的凋亡形态学改变,核染色质凝聚呈"新月形"或形成圆形或椭圆形的凋亡小体;18日龄时,毛囊上皮细胞胞核部分区域退变形成大小不一的类似脂滴的空泡;21日龄时,毛囊上皮细胞退变消失,角化成纤维样的物质;到28日龄时,毛囊上皮细胞完全退变成空洞样结构。由此推断,无毛基因的突变诱发了豫医无毛小鼠皮肤毛囊上皮细胞的凋亡,从而引起小鼠的脱发。

The dorsal skin from Yuyi hairless mice（YYHL）aged 12 to 28 days after birth was studied by electron microscopy.At 12 days,dermal cysts were formed by epithelial cells which clustered in islets.The apoptotic epithelial cells in the hair follicles of skin appeared crescent and the apoptotic bodies were seen in YYHL aged 14 days.Sebocyte-like cells were observed in the cysts of an 18-day-old YYHL.The central part of the cyst was characterized by an accumulation of fibrillar material from degenerative cells on the 21st day.Progressively,the number of cells in these islets increased and a central cavity was formed 28 days after birth.The present results revealed increased apoptosis in epithelial cells of the initial follicular unit,which affected the normal growth of the hair follicle in YYHL.