体外培养小鼠耳蜗Corti器对庆大霉素的吸收

目的 观察庆大霉素-德州红耦联物在体外培养小鼠耳蜗Corti器的分布情况,比较不同时间庆大霉素吸收的差异.方法 分离小鼠耳蜗Corti器,体外培养,培养液中加有庆大霉素-德州红耦联物,分别于培养后3 h、6 h、12 h、24 h、48 h、3 d.4 d和7 d收集标本,荧光染色后行激光扫描共聚焦显微镜观察基底膜庆大霉素的分布情况.结果 小鼠耳蜗Corti器在培养3 h后即可见外毛细胞的纤毛和胞体两侧的胞膜有庆大霉素分布;随着培养时间的延长,庆大霉素在Corti器中的所有细胞均见分布,尤以外毛细胞明显,主要聚集在毛细胞顶端纤毛的下方;培养24 h后庆大霉素在外毛细胞的聚集达到最高峰,而在支持细胞未见明显的聚集;体外培养7 d后在毛细胞胞质中仍可见庆大霉素分布.结论 小鼠Corti器体外培养可用来动态检测庆大霉素在耳蜗细胞的吸收和聚集情况.

Uptake and accumulation of gentamicin by mouse hair cells from the cochlear explants in vitro

OBJECTIVE: To investigate the uptaking and accumulation of gentamicin by mouse hair cells in vitro. METHODS: Cochlear explants were prepared from the microdissected neonatal mouse cochlea. Cochlear explants were cultured with gentamicin-Texas-red conjunction (GTTR) for different time. Laser confocal microscopy was used to observe the distribution of GTTR in the cochlear sensoty cells after labeling with phalloidin-alexa-488. RESULTS: Soon after culture, there was diffuse red staining all tissue cells in the explants. At later time the hair cells were more staining than other cells in the explants. There was no obviously accumulation of GTTR in the supporting cells. The peak level of fluorescent density was reached at 24 hours culture. The GTTR was seen in the infracuticular zone of the hair cells. There was still accumulation of GTTR in the hair cells of the explants after 7 days culturing. CONCLUSIONS: GTTR and cochlea explants were useful methods to investigate the pharmacokinetics and mechanisms of gentamicin accumulation over time.