Woo C C, Oshita M H, Leon M
Department of Psychobiology, University of California, Irvine 92717, USA.
Brain Res. 1996 Apr 15;716(1-2):149-56. doi: 10.1016/0006-8993(96)00037-6.
Olfactory stimulation evokes a column of activity within the olfactory bulb extending from the glomerular layer to the granule cell layer that can be visualized with 2-deoxyglucose autoradiography, optical imaging, Fos protein immunohistochemistry and c-fos mRNA in situ hybridization. The Fos response to odors is typified by the activity of relatively few juxtaglomerular cells, which often occur in foci, and a large number of granule cells extending through much of the bulb. In this study, we characterized the granule cell response to an odor for which young rats had acquired a preference. Fos-like immunoreactive granule cells were quantified by image analysis, and densely stained cells were counted in a region previously shown to be responsive to peppermint odor. We found that odor-trained pups have about half the number of Fos-immunopositive superficial granule cells which respond to a learned odor than do control pups. We then determined whether there was a correlation between the juxtaglomerular cell response and the response of the superficial granule cells deep to those glomerular layer cells. We found a positive correlation between the number of juxtaglomerular cells and the number of granule cells demonstrating Fos immunoreactivity in both control and trained pups, a relationship that changed with early olfactory training.
嗅觉刺激会在嗅球内引发一列从肾小球层延伸至颗粒细胞层的活动，这一活动可用2-脱氧葡萄糖放射自显影、光学成像、Fos蛋白免疫组织化学以及c-fos mRNA原位杂交技术进行可视化观察。对气味的Fos反应的典型特征是相对较少的近肾小球细胞的活动，这些细胞常成簇出现，以及大量贯穿嗅球大部分区域的颗粒细胞的活动。在本研究中，我们对幼鼠已产生偏好的一种气味的颗粒细胞反应进行了特征描述。通过图像分析对Fos样免疫反应性颗粒细胞进行定量，并在先前显示对薄荷气味有反应的区域对深染细胞进行计数。我们发现，经过气味训练的幼崽中，对已习得气味产生反应的Fos免疫阳性浅层颗粒细胞数量约为对照幼崽的一半。然后，我们确定近肾小球细胞反应与这些肾小球层细胞深层的浅层颗粒细胞反应之间是否存在相关性。我们发现，在对照幼崽和经过训练的幼崽中，近肾小球细胞数量与显示Fos免疫反应性的颗粒细胞数量之间均呈正相关，这种关系会随着早期嗅觉训练而改变。
