Abstract
A charge barrier has been found in the glomerular basement membrane of the kidney which plays an important role in the filtration of solutes.
In the present study, we observed electronmicroscopically the anionic sites of the charge barrier in the inner ear of healthy guinea pigs.
Tissues were removed after decapitation and immersed in a solution of cationized polyethyleneimine (PEI, MW 1800).
The results showed an arrangement of PEI particles with two strata in the basement membrane of the epithelium and the capillary.
These sites function as a charge barrier, and their locations in the stria vascularis and the endolymphatic sac may play important roles in the filtration system of water, ions and macromolecules.
