成モルモット蝸牛蓋膜の微細構造に対する再検討
2001 年 11 巻 1 号 p. 25-32
詳細
2001 年 11 巻 1 号 p. 25-32
Recently, low vacuum scanning electron microscope (nSEM) and scanning probe microscope (SPM) had been developed in order to avoid even slight changes in tissue. Employing this new technique, any process of treatment of the specimen is unnecessary, and contamination of artifact is considered to be minimum.
The tectorial membrane is particularly known as soft tissue that easily sustains a damage under the process of preparation and fixation.
The authors used untreated specimen (normal 15 guinea pigs 30 ears) and examined the tectorial membrane using nSEM and SPM. And also analyzed the surface of tectorial membrane using dispersion-typeαwave analyzer.
The results are as follows,
1. The limbal zone of the tectorial membrane was observed as a meshed-like appearance (limbal net) and a structure of pillar was identified lying under it.
2. Covering net in the middle zone was not observed by nSEM, however, under the method of SPM it was detected morphologically and moisture was also content between the fibers of it. This may suggest amorphous substance that covers surface of the tectorial membrane, however, it seemed inconsistent.
3. Former studies reported the marginal zone as a band and ends free, however, it was observed as a pillar structure (marginal pillar) and was tightly attached to the surface of Hensen's cell both by nSEM and SPM.
Strand-like substance was observed in the marginal hole by nSEM. The fibers were not confirmed under SPM, however, moisture was detected here. An unknown substance was considered to exist in the subtectorial membrane space.
4. The result of above was found through all turns of the cochlea.
5. The analysis using dispersion-typeαwave analyzer in three different portions of the tectorial membrane (limbal, middle, and the marginal zone) confirmed that there was no difference between each point, however, in comparison between the untreated specimen and treated tissue, a difference of composition in magnesium, potassium, sodium, phosphorus, sulfur and osmium was noticed. This difference was considered to be due to the treatment of the specimen and in addition, the existence of amorphous substance covering the surface of the tectorial membrane may be suggested.
The authors also considered the function of new structures that have been found in this study.
