Sinakevitch Irina, Bjorklund George R, Newbern Jason M, Gerkin Richard C, Smith Brian H
School of Life Sciences, Arizona State University, PO Box 874501, Tempe, AZ, 85287-4501, USA.
Biol Cybern. 2018 Apr;112(1-2):127-140. doi: 10.1007/s00422-017-0728-8. Epub 2017 Aug 29.
Despite divergent evolutionary origins, the organization of olfactory systems is remarkably similar across phyla. In both insects and mammals, sensory input from receptor cells is initially processed in synaptically dense regions of neuropil called glomeruli, where neural activity is shaped by local inhibition and centrifugal neuromodulation prior to being sent to higher-order brain areas by projection neurons. Here we review both similarities and several key differences in the neuroanatomy of the olfactory system in honey bees, mice, and humans, using a combination of literature review and new primary data. We have focused on the chemical identity and the innervation patterns of neuromodulatory inputs in the primary olfactory system. Our findings show that serotonergic fibers are similarly distributed across glomeruli in all three species. Octopaminergic/tyraminergic fibers in the honey bee also have a similar distribution, and possibly a similar function, to noradrenergic fibers in the mammalian OBs. However, preliminary evidence suggests that human OB may be relatively less organized than its counterparts in honey bee and mouse.
尽管嗅觉系统有着不同的进化起源，但各门类之间嗅觉系统的组织却极为相似。在昆虫和哺乳动物中，来自受体细胞的感觉输入最初都在神经纤维网中突触密集的区域（称为嗅小球）进行处理，在那里，神经活动在通过投射神经元被发送到更高阶脑区之前，会受到局部抑制和离心神经调节的塑造。在此，我们结合文献综述和新的原始数据，回顾了蜜蜂、小鼠和人类嗅觉系统神经解剖学中的相似之处和几个关键差异。我们重点关注了初级嗅觉系统中神经调节输入的化学特性和支配模式。我们的研究结果表明，血清素能纤维在所有这三个物种的嗅小球中分布相似。蜜蜂中的章鱼胺能/酪胺能纤维与哺乳动物嗅球中的去甲肾上腺素能纤维也具有相似的分布，并且可能具有相似的功能。然而，初步证据表明，人类嗅球的组织性可能相对低于蜜蜂和小鼠的嗅球。
