Sensory hair fusion and glycocalyx changes after gentamicin exposure in the guinea pig.

This study demonstrates the mechanism of sensory hair fusion and its relationship to glycocalyx on the inner ear sensory cells of gentamicin-treated guinea pigs, using the ruthenium red staining technique. 0.5 ml containing 5 mg gentamicin sulfate solution was injected in a single dose into the middle ear. After 7 days, various stages of sensory hair degeneration could be observed. The glycocalyx was clearly visualized by ruthenium red. The degeneration starts with a decrease in or even complete loss of glycocalyx in the sensory hairs, with subsequent local adhesion of the plasma membrane in neighbouring hairs. These findings suggest that the glycocalyx of the sensory cell may play an important role in separating the cilia, yet keeping them in a bundle.