Objective      To explore the morphological development process of periphery vestibular organs in inner ear and expression of myosin VI in C57BL/6 mice.       Methods      Using embryo heads from E10 to E17 old mice and embryo inner ears from E18 to E20 old mice

the morphological development process of periphery vestibular organs in C57BL/6 mice inner ear and expression of myosin VI in vestibule on different developmental stages were investigated through frozen serial section

HE staining and immunofluorescence assay.       Results      Vestibular development of mice initiated early and the process was short. Otic capsule arose at E10. The large dorsal vestibular sac (VS) and small ventral cochlear sac (CS) began to form at E11. The differentiation of VS and CS became obvious

and the endolymphatic sac and tube and the superior and posterior semicircular canal primordium arose at E12. The superior and posterior semicircular canal cristae primordium and the lateral semicircular canal and utricle primordium arose at E13. The lateral semicircular canal cristae and   saccule primordium arose at E14. The mature structures of utricle

   saccule and semicircular canal began to form

and all macula and crista ampullaris formed at E15. The morphological development completed at E18. The myosin VI-positive hair cells were found in all macula and crista ampullaris at E15

but no myosin VI expression was detected in supporting cells.       Conclusion       Expression of myosin VI begins at E15

which may be a critical period for hair cell maturation.