The glycocalyx and stereociliary interconnections of the vestibular sensory epithelia of the guinea pig. A freeze-fracture,low-voltage cryo-SEM,SEM and TEM study

In this study freeze fracture, low-voltage cryo-SEM, SEM and TEM were used to characterise the glycocalyx and stereociliary interconnections in the hair cell bundle of the vestibular sensory epithelia of the guinea pig. The glycocalyx resembles a shell-like structure separately surrounding each stereocilium and kinocilium over its entire length. The lateral interciliary connections emerge from the glycocalyx layer, forming an extensive extracellular network maintaining the stereocilia as a bundle. These connections are morphologically similar to the glycocalyx, and grossly oriented in the same direction, indicative of a role in the mechanical transduction system. The matrix material around the glycocalyx also appears to be morphologically similar to the glycocalyx, suggesting the glycocalyx to be even more important in the mechanical transduction system. The tip-links are covered with a layer, which is a continuation of the glycocalyx covering the stereocilia.