Hypercholesterolemia and Auditory Dysfunction

Rabbits were used for the long-term study of auditory function associated with experimental hypertension and hypercholesterolemia. Auditory dysfunction (threshold changes of sound evoked responses) was monitored with an electrode, chronically implanted into the contralateral inferior colliculus. Hypertension was created using the renal encapsulation technique. Auditory function in the hypertension trial demonstrated a dip at higher frequencies as well as improvement at lower frequencies. One gram of cholesterol fed daily for three months was capable of making rabbits atherosclerotic. Cholesterol-fed rabbits showed increasing auditory dysfunction over time at all frequencies. When experimental hypertension was combined with hypercholesterolemia, the auditory changes appeared additive. This work, although in preliminary stages, seems to provide experimental evidence that auditory dysfunction is associated with cholesterol diet.