Calcium-binding sites on sensory processes in vertebrate hair cells.

Abstract

Vertebrate lateral line and vestibular systems center their function on highly mechanosensitive hair cells. Each hair cell is equipped with 1 kinocilium (which resembles a motile cilium) and 50-100 actin-containing stereocilia (which resemble microvilli) at the site of stimulus reception. This report describes EM localization of calcium-binding sites on the sensory processes of vertebrate hair cells. Observation made with the Oschman-Wall technique for Ca localization and with electron-probe X-ray microanalysis of thin sections included: Ca- and Fe-containing deposits in the region of the ciliary necklace in goldfish [Carassius auratus] lateral line hair cells, Ca deposits upon the surface of stereocilia of hair cells of the bullfrog [Rana catesbeiana] inner ear and Ca deposits upon stereocilia of hair cells of the guinea pig [Cavia porcellus] vestibular system.