Research Abstract |
The synthesizing process of the carbohydrate complex and its significant role in the vestibular end organs were investigated in order to reveal the early changes in the vestibular functional disorders. The surface of the vestibular sensory epithelia including sensory, supporting, transitional and dark cells, was covered by fuzzy layers of glycocalyx. It has been indicated that the significant role of the glycocalyx is to keep the cilia arranged in a bundle, to be involved in the sensory cell transduction system, to be related with the controlling mechanisms of the ionic environment of the endolymph and to play an important role for the protection of the supporting cells. The ultrastructural localization of the carbohydrate complexes were also demonstrated using gold-labelled lectins. It has been indicated that the glycocalyx and its associated structures contain N-acetyl-glucosamine, galactose, mannose and sialic acid. These sugars may thus be closely related to the different function of the glycocalyx. In the pathological conditions such as after ototoxic drug administration, endolymphatic hydrops, acoustic overstimulation etc, the first step of degeneration process in the vestibular sensory epithelia was a decrease in glycocalyx or changes of carbohydrate complexes. The further degeneration such as fusion, disarrangement and disappearance of the cilia were all occurred as a result of the damage of glycocalyx.
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