Cochlear deoxyglucose uptake: relationship to stimulus intensity.

The relationship between stimulus intensity and the uptake of 2-deoxyglucose (2-DG) in the cochlea of the gerbil was studied using an autoradiographic technique. In silence, incorporation of labeled 2-DG into stria vascularis and the spiral ligament was significantly higher than for other inner ear structures. With increasing intensity of noise exposure, 2-DG uptake in the spiral ganglion and VIIIth nerve increased dramatically when compared to the lateral wall structures. In contrast, relative 2-DG uptake in the organ of Corti was much less affected by noise exposure. Only at 105 dB SPL, the highest intensity tested, was a modest but statistically significant increase observed in the sensory epithelium. The small change in relative 2-DG uptake observed in the organ of Corti during acoustic stimulation is consistent with Davis' (1965: Quant. Biol. 30, 181-190) battery model of the cochlear transduction process. Alternatively, a larger change may have occurred, but been restricted to a small portion of the epithelium, such as one or both populations of hair cells.