Postnatal Development of the Vestibular Sensory Epithelium in the Mouse

Abstract

The vestibular epithelium of the CBA/CBA mouse was analyzed from birth until the adult stage. Hair cells type I and type II develop in parallel. Initially, the innervation progresses rapidly post partum. A few mature type I hair cells with fully developed nerve calyces occur 4 days post partum. An early temporary innervation of both type I and type II hair cells occurs and is later rebuilt forming mature nerve endings and nerve calyces. Synap-tic bodies develop within the cytoplasm of hair cells without the contact of nerve endings. Efferent nerve endings develop late on both typ I and type II hair cells and moreover are few in the adult animal. The vestibular epithelium is not completely mature until 3–4 weeks post partum.