目的研究将1-分泌酶抑制剂(DAPT)与新生大鼠基底膜共培养,观察其对毛细胞发育和分化的影响。方法采用新生P0大鼠基底膜中圈及顶圈贴壁培养,随机分为正常培养组、DAPT组,按培养时间又分为4天、7天和9天组;其中DAPT为1-分泌酶抑制剂,溶解于终浓度低于0.1%的DMSO,每日换液均加入DAPT。采用扫描电镜观察基底膜毛细胞数量变化。结果正常组顶圈呈1排内毛细胞,2—3排外毛细胞;中圈呈1排内毛细胞,3排外毛细胞,内外毛细胞排列规则,随着培养天数的增加数量无明显变化。DAPT组顶圈呈1排内毛细胞,4—7排外毛细胞;中圈呈1排内毛细胞,4—5排外毛细胞。结论DAPT能够诱导基底膜顶圈产生大量额外的外毛细胞
Objective To study effects of γ-secretase inhibitor DAPT on the development and differentiation of hair ceils when co-cultured with neonatal rat basilar membrane. Methods Middle and apical turn basilar membrane from P0 rats were prepared for adherent culture. Specimens were randomly divided into a normal control group and a DAFT treat- ment group. Specimens were examined after incubation of 4, 7 and 9 days, respectively. The culture medium was replaced every day. DAPT was dissolved in DMSO of a less than 0.1% final concentration in the culture medium. DAPT was added to the medium every day. The distribution of hair cells was examined using scanning electron microscopy. Result The nor- mal control specimens showed one row of inner hair cells and two or three rows of outer hair cells in the apical turn, and three rows of outer hair cells in the middle turn, with minimal variations. In DAPT-treated specimens, there were one row of inner hair cells but four to seven rows of outer hair cells in the apical turn, and four or five rows of outer hair cells in the middle turn. Conclusion DAPT induces generation of large amount of additional outer hair cells in the apical turn of postna- tal organs of Corti.