Vestibular dark cells

Vestibular dark cells are specialized ion-transporting epithelial cells located in the vestibular apparatus of the inner ear, near the sensory epithelia. They are responsible for secreting potassium ions (K+) into the endolymph, thereby generating and maintaining the unique high-potassium, low-sodium composition of this fluid, which is essential for the proper function of vestibular hair cells in detecting balance and head movement.