Auditory brainstem response in hyperbilirubinemic rats: Part II.

The effect of an albumin-bilirubin solution on the auditory brainstem response (ABR) of rats was examined and compared with that of rats in which only bilirubin was administered. In albumin-bilirubin-loaded rats, the latencies of waves II and IV were prolonged and the amplitudes decreased, whereas the ABR wave I did not change significantly. The I-IV interpeak latency also was prolonged. These changes were more severe in rats loaded only with bilirubin. Mannitol injection hastened the appearance of ABR changes when only bilirubin was used, but peak levels of ABR changes were almost the same in the mannitol-injected groups. When the blood-brain barrier is intact, albumin administration is useful in hyperbilirubinemia for the prevention of damage to the central auditory pathways. The reversibility of the ABR changes were demonstrated in all bilirubin-administered groups.