Abstract：ObjectiveTo study the role of N-methyl-D-aspartate-receptor (NMDAR) expression in the development of hearing damage in neonatal rats with hyperbilirubinemia. METHODS: Sixty seven-day-old Sprague-Dawley rats were randomly injected with bilirubin of 100 μg/g (low-dose treatment group) or 200 μg/g (high-dose treatment group) or normal saline (control group). Auditory brainstem response (ABR) was examined. The concentrations of bilirubin in blood and brain were measured. NMDAR expression in the cochlear nucleus slices was examined by immunohistochemistry assay. RESULTS: ABR reflecting threshold obviously increased, and I, II and III wave latency as well as I-II, II-III and I-III interval were more prolonged in the two bilirubin treatment groups when compared with the control group. The NMDAR expression in the cochlear nucleuse in the two bilirubin treatment groups was obviously lower than that in the control group. The NMDAR expression in the cochlear nucleuse was negatively correlated with the brain bilirubin content and the ABR reflecting threshold in the two bilirubin treatment groups. CONCLUSIONS: An increased NMDAR activity may play an important role in hearing damage following hyperbilirubinemia.［Chin J Contemp Pediatr, 2010, 12 (3):201-204］
LI Ke-Fang,DU Kai-Xian,JIANG Yue-Xing et al. NMDAR expression in the cochlear nucleus and hearing damage in neonatal rats with hyperbilirubinemia[J]. CJCP, 2010, 12(3): 201-204.
［1］Rhee CK, Park HM, Jang YJ . Audiologic evaluation of neonates with severe hyperbilirubinemia using transiently evoked otoacoustic emissions and auditory brainstem responses［J］. Laryngoscope, 1999, 109(12):2005-2008.
［2］Inglefield JR, Schwartz-Bloom RD. Activation of excitatory amino acid receptors in the rat hippocampal slice increase intracellular Cl-and cell volume［J］. J Neuochem, 1998, 71(4):1396-1404.
［3］Simmons JL, Beauchaine KL. Auditory neuropathy: case study with hyperbilirubinemia［J］. J Am Acad Audiol, 2000, 11(6):337-347.
