C_(57)BL/6遗传背景下无毛突变基因对胸腺及皮肤结构的影响

目的　探讨在C57BL/6背景下突变基因对胸腺及皮肤结构的影响。方法　观察脱毛规律 ,并用常规组织学方法对 19日龄正常C57BL/6小鼠及C57BL/6无毛小鼠的胸腺及皮肤结构进行了对比观察。结果　C57BL/6无毛小鼠 12日龄左右发生脱毛现象 ,2周左右时间除触须外全部脱净 ,并终生保持无毛状态 ;随年龄增长 ,头部、腹部和体侧形成特别的皱纹和褶痕 ,似犀牛状 ,指甲过度生长。皮肤有黑色素沉着 ,而且表面出现一些小的丘疹。组织学发现 19日龄C57BL/6无毛小鼠皮肤表皮有一层角化的角质层 ,毛干消失 ,毛囊腔宽大 ,在真皮深部可见毛球的残余部分 ,皮脂腺结构正常。 19日龄C57BL/6无毛小鼠胸腺的形态、结构与对照鼠无明显差异 ,但萎缩较早。结论　无毛突变基因影响C57BL/6小鼠的毛发周期和胸腺退化

The Effect of Hairless Mutant Gene on The Thymus and Skin Under The C57 BL/6 Genetic Background

Objective To study how the mutation gene affects the thymus and skin of the C 57BL/6 hairless mice. Methods The procedure of shedding hair and histological structure on the thymus and skin of the C 57BL/6 hairless mice in 19 days were studied,and compared with C 57BL/6 mice of the same age. Results The C 57BL/6 hairless mice developed a normal coat up to the age of 12 days,but then lost all hair.At the age of 4 weeks the hairless-like mutant mice become essentially naked except for some vibrissae,and grew no new hair.With increased age,the mutant skin form folds and flaps and had rhinoceros-like appearance.The claws were noticeably elongated.Mutant mice had heavily pigmented skin,and had some small papules on the surface of skin.Histologically,There was keratotic cuticular layer in the epidermis.The hair follicle of C 57BL/6 hairless mice in 19 days lost shaft to distend to be lenient cavity, some follicles contained keratin fragments.The Remains of hair papilla became trapped deep in the dermis.Sebaceous glands were well developed.As for the morphology and structure of thymus in 19 days,there was no distinct difference between C 57BL/6 hairless mice and normal mice,but the thymus of hairless mice atrophy early than that of contrast mice. Conclusion The hairless mutant gene effects hair follicles cycle and thymus degeneration of the C 57BL/6 hairless mice.