Mario H. Burgos

The fine structure of the stria vascularis of the guinea-pig inner ear

SummaryThe stria vascularis lining the external wall of the cochlear duct is a thick epithelium consisting of three cell types, with numerous blood capillaries embedded within it. The columnar marginal cells have extensive lateral and basal infoldings of the plasma membrane with each compartment, formed by these infoldings, filled with clusters of mitochondria. Marginal cells have numerous pinocytotic-like vesicles located in the apical region and few short microvilli on the luminal surface. The surface of the cell has a thick unit membrane.Intermediate and basal cells are irregular in shape, have a clear cytoplasm with a few organelles and some pigmentary inclusions and have extensive cytoplasmic processes which interdigitate with the other cells or make direct contac with the basal lamina of the capillaries. Ascending prolongations from a number of basal cells isolate the infolded membrane complex of each marginal cell in a cup-like arrangement. Basal cells limit the stria vascularis and demarcate it from the spiral ligament and from the spiral prominence.