Pigmented epithelial cells of the membranous saccular wall of the chinchilla.

Abstract

The posterior-superior portion of the membranous wall of the chinchilla saccule is lined by pigmented epithelial cells which contain golden brown granules having three components (lipid droplets, granular matrix, and dense globules). Histochemical and electronmicroscopic studies indicate that the dense component is a form of melanin. The pigmented cells show morphological features suggestive of fluid transport function; they are also involved in decalcification and phagocytosis of otoconial crystals. These findings provide evidence that the saccular wall epithelium plays an active role in regulating endolymph composition and in clearance of debris from the endolymphatic space.