What Are Angioid Streaks?

Located on the outer wall of the volute, it is a special stratified epithelium containing capillaries, which can produce endolymph. The cochlea is formed by surrounding the central conical snail shaft of the meningeal cochlea during the intubation period of the bone cochlea. Vascular striae are special stratified epithelial tissues that contain capillaries inside. Endolymph can be produced as a result.

Located on the outer wall of the volute, it is a special stratified epithelium containing capillaries, which can produce endolymph. The cochlea is formed by surrounding the central conical snail shaft of the meningeal cochlea during the intubation period of the bone cochlea. Vascular striae are special stratified epithelial tissues that contain capillaries inside. Endolymph can be produced as a result.

Chinese name

Blood vessel pattern

Foreign name

stria vascularis

Location

Volute outer wall

Nature

Capillary stratified epithelium

Vessel pattern I. Ultrastructure:

Vessel veins mainly include three cell components: marginal cells (MC), i-ntermediate cells (IC) and basal cells (BC). They have their own structural features and functions.

(A) edge cells:

Scanning electron microscopy showed that the surface of the marginal cells was spherical, with many microvilli, and the surface of the cell cavity contained a single moving ciliary; under transmission electron microscopy, there were many protrusions in the lower part of the cell body extending to the base of the vascular stratum, and the basal cell membrane had many folds. Contains a large number of mitochondria. The marginal cells are near the endothelium, which are divided into two parts, the basal layer and the top layer, according to their location. The connection between the two and the intermediate cells is not the same. The foot-like and enlarged processes at the base of the marginal cells and the surrounding intermediate cells are formed. There is a special space between the basal subtypes, and part of K is absorbed through this special space; while the apical part of the marginal cells forms a primary process filled with mitochondria and a large number of secondary processes connected to it, which are rich in Na / K-ATPase. The secondary process penetrates between the surface layers of the blood vessel striatum, and through this, K is absorbed from the apical subtype of the intermediate cell, and K is secreted to the endolymph.

(2) Intermediate cells:

It constitutes the main body of the vascular striae epithelial layer, which is discontinuously surrounded by cells, and surrounds the hair cell vascular network. The intermediate cell is a melanocyte that migrates and differentiates from the neural crest and intersects with the protrusions of the other two cells. Recently, researchers have divided the intermediate cells into basal and apical subtypes. The basal subtypes of the intermediate cells form leaf-like horizontal protrusions completely covering the basal cells, while the apical subtypes of the intermediate cells are mainly located in the apical epithelium of the vascular striae and Intermediate cell basal subtypes are widely connected with basal subtypes. The apical subtypes of dendritic processes intersect with surface edge cells. The role of this type of cell is to absorb basal subtype cells that do not enter the basal cell processes. K.
The apical and basal processes of the marginal cells are different. Similarly, the basal subtypes of the intermediate cells are different from the apical subtypes. The difference indicates that the vascular pattern has two layers of structures: the top intermediate cells and the marginal cells, and the basal intermediate cells and the marginal cells. These two layers of structures indicate that the basal layer of the blood vessel pattern and the top layer may have different physiological functions. The basal layer may be related to the generation of endolymph potentials, while the top layer has the function of secreting K.

(3) Basal cells:

From the mesenchymal cells during development, the basal part of the blood vessel pattern is formed, separating the blood vessel pattern from the spiral ligament below it. Basal cells are juxtaposed to form a tightly connected whole. During the development process, the formation of tight junctions is compatible with the generation of endolymph potentials.
Extensive tight connections exist between basal cells of vascular striae, basal cells and intermediate cells, and fibrous cells of the spiral ligament. They form a functional community in which basal cells play a central role. There is no gap junction structure in the cell membrane of the marginal cells and the junction between the basal cells and the marginal cells. It is functionally separated from the functional community of intermediate cells-basal cells-spiral ligament fibroblasts. Each edge cell is a Independent functional body.