Three-dimensional features of the striated organelle in the vestibular hair cell.

The striated organelle, the Friedmann's body, of the vestibular hair cells in normal guinea pigs were examined using a freeze-fracture-etch technique. The striated organelles were composed of periodic parallel loose spirals of two fine fibrils, the thick strands. This main distance was divided by thin strands, and many fine fibrils cross-linked the thick strands to the central thin strands. Stereo-micrography showed that the thin strands were positioned on a different plane from that of the thick strands and that the thin strands were cross-linked with thick strands by fine fibrils in a radiating pattern, giving them a columnar appearance.