Apoptosis to cleft palate development in mice.

本研究假设细胞凋亡参与了二级腭架融合过程中上皮细胞的消失。5-溴脱氧尿苷（BrdU）于妊娠11-13天（塞天=0）腹腔注射给妊娠ICR小鼠，故意让细胞程序性死亡紊乱，制作腭裂模型小鼠。正常组和BrdU组分别用形态学和免疫组化方法观察腭架尖端的细胞活动。正常组在立体显微镜下观察细胞上硫酸尼罗蓝染色。结果识别出尼罗河蓝阳性细胞，融合区巨噬细胞聚集。BrdU组出现腭裂，腭架尖端内边缘上皮未见尼罗蓝阳性细胞。正常组的H-E染色证实二级腭架融合后间充质组织中存在上皮休息和凋亡小体。BrdU组腭壁分离，中线鳞状上皮缝比鼻侧和口腔侧表皮薄。采用TUNEL免疫组化方法观察细胞DNA片段，并将肿瘤坏死因子家族Fas/Fas配体系统作为细胞凋亡的执行过程。结果识别出正常组阳性细胞，未识别出BrdU阳性细胞。腭内缘上皮的消失与细胞凋亡有关，brou诱导腭裂的发生机制与细胞凋亡的不完全性有关。

This study hypothesized that apoptosis participates in disappearance of epithelial cell in fusion of secondary palatal shelves. 5-bromodeoxyuridine (BrdU) was administered to pregnant ICR mice by intraperitoneal injection at 11-13 day of gestation (plug day=0), and we made cleft palate model mouse by letting programed cell death be out of order intentionally. In normal group and BrdU group, cell action of the palatal shelf tips were observed by morphology and immunohistochemistry. In mormal group, supravital Nile blue sulphate staining was observed by using stereoscopic microscope. The result recognized Nile blue positive cells which showed accumulation of macrophage in fusion region. Cleft palate was observed in BrdU group, and Nile blue positive cells were not recognized in the medial edge epithelium of the palatal shelf tips. Epithlial rest and apoptotic body was confirmed during mesenchymal tissue after fusion of secondary palatal shelves in H-E staining of norma group. The palatal shelves were apart in BrdU group, and midline squamous epithelium seam to be thinner than epidermis of nasal cavity side and oral side. Furthermore, DNA fragmentation which used TUNEL method for immunohistochemistry was observed, Fas/Fas ligand sysyem which was TNF (tumor necrosis factor) family as execution course of apoptosis was referred. The result recognized a positive cell in normal group and didn't recognize positive cells with BrdU.The disappearance of palatal medial edge epithelium after fusion of secondary palatal shelves was suggested by the apoptosis, and the mechanisms of BroU-induced cleft palate was regarded as a thing by nonfulfillment of apoptosis.