Prenatal and Early Postnatal Odorant Exposure Heightens Odor-Evoked Mitral Cell Responses in the Mouse Olfactory Bulb.
Prenatal and Early Postnatal Odorant Exposure Heightens Odor-Evoked Mitral Cell Responses in the Mouse Olfactory Bulb.
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DOI：
10.1523/eneuro.0129-17.2017
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发表时间：
2017-09
期刊：
影响因子：
3.4
通讯作者：
Urban NN
中科院分区：
文献类型：
--
作者：
Liu A;Urban NN
早期的感觉经验塑造了感觉回路的解剖结构和功能。在小鼠嗅球（OB），出生前和出生后早期的气味暴露通过气味的食物（食物/气味配对）不仅增加了激活的肾小球的体积，但也增加了二尖瓣和簇状细胞（M/TC）连接到激活的肾小球的数量。考虑到M/TC在OB输出和介导侧抑制网络中的重要性，增加连接到单个肾小球的M/TC的数量可以通过增加该肾小球的总输出和/或通过增加由连接到受影响肾小球的细胞介导的侧抑制的强度来显著改变气味表示。在这里，我们试图了解这种长期气味暴露模式对二尖瓣细胞（MC）群体活动的功能影响。我们使用病毒表达的GCaMP 6s检查气味诱发的反应的MC出生前和出生后早期的气味暴露于两种不同的气味，水杨酸甲酯（MS）和己醛，这都是强激活剂的肾小球背侧OB表面。以前的工作表明，气味熟悉性可能会降低气味诱发的MC反应在啮齿动物。然而，我们发现，早期的食物为基础的气味暴露显着改变MC的反应，在一个意想不到的方式，导致广泛的幅度增加，数量和可靠性的兴奋性MC响应整个背OB。
Early sensory experience shapes the anatomy and function of sensory circuits. In the mouse olfactory bulb (OB), prenatal and early postnatal odorant exposure through odorized food (food/odorant pairing) not only increases the volume of activated glomeruli but also increases the number of mitral and tufted cells (M/TCs) connected to activated glomeruli. Given the importance of M/TCs in OB output and in mediating lateral inhibitory networks, increasing the number of M/TCs connected to a single glomerulus may significantly change odorant representation by increasing the total output of that glomerulus and/or by increasing the strength of lateral inhibition mediated by cells connected to the affected glomerulus. Here, we seek to understand the functional impact of this long-term odorant exposure paradigm on the population activity of mitral cells (MCs). We use viral expression of GCaMP6s to examine odor-evoked responses of MCs following prenatal and early postnatal odorant exposure to two dissimilar odorants, methyl salicylate (MS) and hexanal, which are both strong activators of glomeruli on the dorsal OB surface. Previous work suggests that odor familiarity may decrease odor-evoked MC response in rodents. However, we find that early food-based odorant exposure significantly changes MC responses in an unexpected way, resulting in broad increases in the amplitude, number, and reliability of excitatory MC responses across the dorsal OB.