鸡前庭感觉上皮细胞的再生能力与细胞增殖特点

Patterns of cell proliferation in the avian vestibular epithelium onphysiological and pathological condition

目的 :探讨鸟纲动物前庭感觉上皮细胞在生理和病理条件下的再生能力和细胞增殖活动特点。方法 :庆大霉素 6 0mg/kg(体重 )给鸡大腿肌肉注射 (庆大霉素中毒组 ) ,每天 1次 ,共 10d ;分别于庆大霉素注射后1、7d ,经腹腔内注射 5 溴脱氧尿核苷 10 0mg/kg ,6h后处死动物 ,取颞骨制备内耳石蜡切片 ,应用免疫组织化学染色方法 ,观察病理状态下前庭感觉上皮细胞增殖活动。生理条件组不接受庆大霉素注射 ,其余步骤均同庆大霉素中毒组 ,以观察生理条件下的细胞增殖状态。结果 :生理状态下 ,鸡前庭器官 ,包括椭圆囊斑、球囊斑及壶腹嵴感觉上皮存在数量很少的标记支持细胞和标记毛细胞。而在庆大霉素中毒损伤后 ,被标记的阳性细胞 ,包括支持细胞和毛细胞数量显著增多。随庆大霉素中毒时间的延长 ,标记细胞向腔面迁 g的趋势明显 ,许多标记毛细胞与标记支持细胞成对出现 ,呈直线排列。结论 :鸡前庭器官的细胞增殖活动是一个可动态调节的过程 ,生理状态下 ,细胞增殖的数量和速率呈低水平 ,但在庆大霉素损伤后 ,表现为上调 ,即细胞增殖活动显著活跃 ;支持细胞可能是再生毛细胞的前体细胞。

Objective:To investigate the characteristic of cell proliferation in chick vestibular epithelium upon physiological and pathological condition.Method:The chicks received daily intramuscular injections of gentamicin sulfate(60 mg/kg) for 10 days.At 1,7 days after the last GM injection,the chicks received an intraperitoneal injection of 5-bromodeoxyuridine (BrdU;100 mg/kg),and 6 hours later,they were sacrificed and the temporal bones were removed and prepared for Brd U immunohistochemistry to examine the mitotic activity in chick's vestibular epithelium.In physiological group,animals only received an intraperitoneal injection of BrdU.Result:A small number of labeled hair cells and supporting cells were found on physiological basis in all ampullary and otolithic organs, however the treatment group had a much larger number of labeled cells than the untreated animals.The labeled hair cells can immigrate and locate finally at the surface layer of the vestibular epithalium.Additionally,in many tissue sections,more than half of the labeled hair cells are aligned with labeled supporting cells.Conclusion:The level of cell proliferation in the chick's vestibular system can be up-treated in response to a lesion.The supporting cells may be progenitors of the regenerated vestibular hair cells.