Age-related synaptic changes in the anteroventral cochlear nucleus of Fischer-344 rats.

Previous studies have demonstrated age-related decreases in the transmitters glycine and glutamate in the cochlear nucleus (CN) of the Fischer-344 (F344) rat, along with declining levels of binding for glycine receptors. The purpose of this study was to evaluate structural correlates to the transmitter and receptor losses that accompany aging in the anteroventral CN (AVCN). Thin sections were obtained from the middle-frequency area of the right AVCNs from five 3-month-, four 19-month-, and five 28-month-old F344 rats.

Hsp70 in the inferior colliculus of Fischer-344 rats: effects of age and acoustic stress.

Heat shock proteins 72 and 73 (hsp72 and hsp73) were studied in the inferior colliculus (IC) of Fischer-344 rats to determine if their levels are altered during normal aging and following exposure to intense acoustic noise. Three age groups of rats (3, 18, and 25 months) were exposed to ambient sound (control) or broad-band noise at 108 dB sound pressure level (0.0004 dyn/cm2) for 30 min.