Innervation of cholinergic vestibular efferent system in vestibular periphery of rats

Abstract

The innervation of cholinergic efferent fibers in the vestibular endorgans of the rat was investigated using a modified preembedding immunostaining technique of immunoelectron microscopy. A monoclonal antibody to choline acetyltransferase (ChAT) was used as a marker of cholinergic fibers. It was found that there were four types of cholinergic innervation in the vestibular endorgans of the rat: (1) cholinergic nerve endings formed axo-dendritic synapses with afferent chalice surrounding the type I sensory hair cells; (2) cholinergic nerve endings formed axo-somatic synapses with type II hair cells; (3) cholinergic fibers synapse with afferent nerve fibers and (4) a synaptic contact developed between cholinergic nerve endings. The results demonstrated that a multiform innervation of the cholinergic efferents exists in the rat vestibular periphery.

Keywords

acetylcholine / cholinergic nerve fiber / efferent / immunocytochemistry / vestibular sensory periphery / rat

References

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