Influence of thyroid state and improved hypoxia tolerance on noise-induced cochlea damage.
Guinea pigs were exposed to pure tone noise (2.7 kHz, 130 dB, 1 h) and cochlear microphonic potentials were measured 24 h after exposure. There is the possibility to modify the resulting noise-induced cochlea damage by regulating the function of the thyroid gland to alter the rate of metabolism. A hypofunction of the thyroid gland during sound exposure lessens, an over-function aggravates the damage. After gradual adaptation of the animals to a simulated 10,000 m altitude, the electrophysiologically demonstratable noise-induced damage was reduced. This might be explained by the greater hypoxia tolerance and perhaps additional better oxygen supply to the receptor cells.
D000531:Altitude; D000818:Animals; D003051:Cochlea / Q000293:injuries*; D004734:Energy Metabolism; D006168:Guinea Pigs; D006317:Hearing Loss, Noise-Induced; D000860:Hypoxia; D013961:Thyroid Gland / Q000502:physiology*; D013965:Thyroidectomy; D013974:Thyroxine / Q000008:administration & dosage
D013974:Thyroxine