The roles of vasopressin and aquaporins in water transport

Abstract

　The membranous labyrinth is composed of the endo and perilymphatic spaces. The endolymphatic space is filled with endolymph, a K-rich and positively polarized fluid, whereas the surrounding perilymphatic space is filled with perilymph, with a composition similar to the usual extracellular fluid. The homeostasis of the inner ear fluid is essential for maintenance of audio-vestibular function. Since the discovery of aquaporin water channels, it has become known that these channels play a crucial role in inner ear fluid homeostasis. In this paper, experimental evidence to support the above-mentioned hypothesis will be presented mainly based on our recent studies.