抄録
The sequential changes of cochlear compound action potentials (CAPs) following transient cochlear ischemia was studied in the gerbil to reveal if transient ischemia causes delayed neuronal death of the organ of Corti. For chronic reading of the CAPs, a platinum wire electrode was inserted into the facial canal through the stylomastoid foramen. Cochlear ischemia was created by occluding the bilateral vertebral arteries for 5 minutes, as the posterior cerebral communicating arteries are lucking and the labyrinthine arteries are supplied only by the vertebral arteries in the gerbil. Occlusion of the vertebral arteries caused remarkable increase in the CAP threshold, which subsequently recovered after recirculation. Hearing impairment recovered completely during the 1st and 3rd day of ischemia in all animals (n=6). However, the threshold increased again after the 5th day. The increase was more than 10dB at the 10th day in 3 of 6 (50%) animals.
