耳石膜の形態的観察

抄録

Morphological studies were made of the otolithic membrane in its normal and pathological states in guinea pig, mice and squirrel monkey using scanning and transmission electron microscopes.
The otolithic membrane normally consists of three layers; the first layer, situated nearest the endolymph, is an otoconial layer wherein otoconia of calcite form of varying sizes are contained; the second and third layers are made up of a gelatinoid substance which forms meshes similar to those of fibrous tissues. Sensory hairs of sensory cells were found to be in contact with these gelatin layers but not with otoconia. The two gelatin layers are considered to play the role of fixing otoconia on the macula. Electron microscopic pictures provided evidence that the dark cells of the utricle are able to absorb otoconia.
The intratympanic cavity injection of ototoxic drugs, on the other hand, was followed by degeneration of sensory cells as well as by a reduction in or the disappearance of otoconia or the appearance of giant otoconia or mosaic like clusters of otoconia.
Changes in the otolithic organ that were observed following loading with impact sounds were not only alterations due to excessive mechanical stimuli but also those suggestive of metabolic disturbances, e. g. irregularities of architecture of the gelatin layers and an augmentation of the accessory membrane.
In this presentation mention was thus made of findings on morphology of the otolithic membrane and those pertinent to the metabolism of the otoconia.