大鼠嗅球在不同年龄阶段的Fos表达

FOS EXPRESSION IN OLFACTORY BULB OF RAT IN DIFFERENT AGE

本实验用免疫组化方法检测大鼠嗅球在不同年龄阶段的Fos表达.结果如下:胚鼠18天时,嗅球颗粒细胞层最先出现少许Fos阳性神经元.随后至P7天前Fos阳性神经元以缓慢速度逐渐增多.僧帽细胞层和小球层的Fos阳性神经元出现较颗粒细胞晚,僧帽细胞在P7天、小球旁细胞在P10天才出现Fos表达.从P14天以后这三层的Pos阳性神经元数有较明显的增多,到P30天达第一次高峰,P40天稍有下降,P50天颗粒细胞层的Fos阳性神经元数又有所上升,P60天达第二次高峰,但僧帽细胞层和小球层的Fos阳性神经元却逐渐减少.到成年期(3个月),颗粒细胞层仍有少量的Fos阳性神经元,但僧帽细胞层和小球层不再表达Fos.而在老年期(30个月),整个嗅球已没有Fos的表达.因此本结果提示:①嗅球出现FOS表达的顺序是:颗粒细胞--僧帽细胞—小球层细胞,而消失的顺序则相反,这提示分化越早的细胞其保持分化的能力越长,而分化越晚的细胞其保持分化的能力越短;②嗅球三细胞层出现较多的Fos阳性神经元是在P30天至P60天,提示大部分细胞的分化期主要集中在生后30～60天之间.

The purpose of this article is to detect Fos expression in olfactory bulb of rat in different age by immunocytochemistry. The results showed that as follow: Fos expression first appears in the granular cell layer of olfactory bulb at embryonic day 18 ( E18) . The Fos positive neurons increase slowly untill postnatal day 7 ( P7) . They are initially foud in mitral cell layer at P7 and in glomerular layer at P10. From P14 , the number of Fos positive cells in these three layers grows up obviously and reaches to the first peak at P30. But it declines slightly at P40, then increases again at P50 and arrive at the second peak at P60. At adult, some Fos positive cells are still found in the granular cell layer. However there is no Fos expression in the mitral cell layer and glomerular layer. And in the aged period, no Fos expression can be seen in tha whole olfactory bulb . So the results shows : (1) that the order of Fos expression article. In these three layers of the olfactory bulb, is from granular layer to mitral layer then to glomerular layer, whereas it is just oppisite when Fos expression disappaers, which suggest the earlier the cells differentiate,the longer they keep the ability of differenciation. (2) the differentiated period of most cells of olfactory bulb is mainly between P30-P60.