Jalenques I, Burette A, Albuisson E, Romand R
USN1, Centre Médico-Psychologique, CHU Saint-Jacques, Clermont-Ferrand, France.
Hear Res. 1997 May;107(1-2):113-24. doi: 10.1016/s0378-5955(97)00026-9.
The age-related changes in the ventral cochlear nucleus (VCN) as revealed by glial fibrillary acid protein (GFAP) immunoreactivity were analyzed in the following age groups: 3-, 6-, 12-, 18-, and 24-month-old Sprague-Dawley rats. A cartographic and a quantitative analysis showed a significant increase in the number of GFAP positive astrocytes during the first year of life and a significant decrease in older rats. We also observed an age-induced modification in the spatial distribution of GFAP positive astrocyte. In the anterior part of the VCN of the 3- and 6-month-old rats, we observed a significant decrease in the rostro-caudal as well in the dorso-ventral axes. In the posterior part of the VCN, a significant decrease in the dorso-ventral axis could be also observed, but no significant difference in the spatial distribution was obtained in the rostro-caudal axis. In older rats, the distribution appeared homogeneous throughout the nucleus. Additionally, aging was associated with a significant increase in GFAP positive astrocyte sizes, except for immunolabelled astrocytes in the granule cell layer. The different levels of GFAP expression occurring in the VCN during normal aging could reflect a progressive decline of cellular activity in the VCN, without severe cell degeneration or synaptic loss.
利用胶质纤维酸性蛋白（GFAP）免疫反应性分析了以下年龄组的腹侧耳蜗核（VCN）与年龄相关的变化：3、6、12、18和24月龄的Sprague-Dawley大鼠。制图分析和定量分析显示，在生命的第一年，GFAP阳性星形胶质细胞的数量显著增加，而在老年大鼠中则显著减少。我们还观察到GFAP阳性星形胶质细胞的空间分布随年龄发生了改变。在3月龄和6月龄大鼠VCN的前部，我们观察到其在 rostro-caudal 轴以及背腹轴上均显著减小。在VCN的后部，也可观察到背腹轴显著减小，但在rostro-caudal轴上未获得空间分布的显著差异。在老年大鼠中，整个核内的分布显得均匀。此外，衰老与GFAP阳性星形胶质细胞大小的显著增加有关，但颗粒细胞层中的免疫标记星形胶质细胞除外。正常衰老过程中VCN中出现的不同水平的GFAP表达可能反映了VCN中细胞活性的逐渐下降，而没有严重的细胞变性或突触丧失。
