地塞米松诱导胎鼠腭裂形成过程中鼻中隔软骨Bcl-2基因的表达

目的研究地塞米松诱导的腭裂胎鼠鼻中隔软骨Bcl-2基因的表达及其对鼻中隔软骨细胞发育的影响。方法选取孕鼠30只,随机分为实验组和对照组,实验组于11.5GD孕期（gestation day）鼠腹腔注射磷酸地塞米松（50mg/kg）,对照组以等剂量生理盐水代替。分别于12.5、13.5、14.5、15.5、16.5GD处死孕鼠,取胎鼠头部石蜡包埋,切片厚5μm。行HE染色和免疫组化染色,检测胎鼠鼻中隔软骨细胞中Bcl-2的表达。结果12.5、13.5GD几乎无Bcl-2蛋白表达;14.5、15.5、16.5GD鼻中隔软骨细胞中Bcl-2阳性信号强度和阳性细胞数密度依次递增,而同一时间点实验组阳性细胞数密度低于对照组。实验组和对照组胎鼠鼻中隔软骨细胞形态和数量随胚胎发育而变化。结论地塞米松诱导的腭裂胎鼠鼻中隔软骨细胞Bcl-2的低表达使细胞过度凋亡,影响鼻中隔发育,参与了腭裂的形成过程。

Bcl-2 gene expression in nasal septum cartilage in the Dexamethasone-induced cleft palate embryonic mice

Objective To determine the expression and effect of Bcl-2 gene on the development of nasal septum cartilage in dexamethasone（DEX） -induced cleft palate embryonic mice. Methods 30 pregnant mice were randomly divided into experimental group（EG） and control group（CG） . DEX was given in a dose of 50 mg/kg via intraperitoneal injection on in EG on 11.5 GD. Isodose normal saline was given for GC. Mice were sacrificed on 12.5、13.5、14.5、15.5、16.5GD.The embryonic head were embedded with paraffin on coronal plane,sectioned at 5 μm,followed by HE and Bcl-2 immunohistochemistry staining. Bcl-2 expression was determined in the cells of nasal septum cartilage. Results On 12.5 GD and 13.5 GD,no Bcl-2 protein expressed in the nasal septum. The Bcl-2 positive signal and NA gradually increased from 14.5 GD to 16.5 GD. Fewer Bcl-2 positive cells on EG were observed than that of CG on the same time. The morphology and the numerical densities on area of cells in nasal septum cartilage changed as the embryo developed. Conclusion Bcl-2 low expression induces cells apoptosis in nasal septum cartilage and thin,small nasal septum on EG,which resulted in cleft palate formation.