Domestic cat nose functions as a highly efficient coiled parallel gas chromatograph.
Domestic cat nose functions as a highly efficient coiled parallel gas chromatograph.
复制标题
DOI：
10.1371/journal.pcbi.1011119
复制
发表时间：
2023-06
影响因子：
4.3
通讯作者：
中科院分区：
文献类型：
--
作者：
哺乳动物感觉器官的外围结构通常支持它们的功能，例如毛细胞与内耳的机械特性的排列。在这里，我们通过建立一个解剖学上精确的家猫（Felis catus）鼻腔计算模型，基于高分辨率微ct和顺序组织学切片，研究了哺乳动物嗅觉的结构-功能关系。我们的研究结果显示了呼吸和嗅觉流动机制的明显分离，具有高速的背内侧流，增加了气味传递到筛状嗅觉区域的速度和效率，同时又不影响鼻子的过滤和调节目的。这些结果证实了先前在其他哺乳动物物种中的发现，这暗示了一个共同的主题，即处理头部的物理尺寸限制，限制了鼻导气管作为直管的长度无限增加。因此，我们假设这些筛状嗅觉通道的功能是平行的盘状色谱仪通道，并进一步表明，在安静呼吸状态下，猫鼻子中的理论板数（一种广泛使用的气相色谱仪效率指标）比适合类似颅骨空间的“两栖类”直通道高100倍以上。平行特性还降低了每个线圈内的气流速度，这对于实现高板数至关重要，同时从高速背中流集体进料，因此不会牺牲总气味采样速度。筛鼻甲骨的出现是哺乳动物进化的重要一步，与它们的嗅觉功能和大脑发育有关。我们的发现揭示了这种结构如何促进更好的嗅觉表现的新机制，进一步加深了我们对哺乳动物物种（包括F. catus，一种受欢迎的宠物）对不同环境的成功适应的理解。哺乳动物鼻子中出现的螺旋状鼻甲结构，与另一种感觉器官——蜗牛状的螺旋耳蜗非常相似，这也是哺乳动物所特有的。在鸟类和其他非哺乳动物的脊椎动物中，内部听觉器官，尽管被称为“耳蜗”，实际上是一个盲端管。虽然哺乳动物耳蜗的进化增强了我们的听觉频率敏感性和范围，但哺乳动物嗅鼻甲的功能效益只是推测。利用解剖学上精确的计算模型，我们发现，作为一个模型，家猫的旋转鼻甲结构可以作为一个平行的螺旋色谱仪，显著提高气味传递速度和色谱效率：与“类两栖动物”的直鼻通道相比，这一速度和色谱效率要高100倍。
The peripheral structures of mammalian sensory organs often serve to support their functionality, such as alignment of hair cells to the mechanical properties of the inner ear. Here, we examined the structure-function relationship for mammalian olfaction by creating an anatomically accurate computational nasal model for the domestic cat (Felis catus) based on high resolution microCT and sequential histological sections. Our results showed a distinct separation of respiratory and olfactory flow regimes, featuring a high-speed dorsal medial stream that increases odor delivery speed and efficiency to the ethmoid olfactory region without compromising the filtration and conditioning purpose of the nose. These results corroborated previous findings in other mammalian species, which implicates a common theme to deal with the physical size limitation of the head that confines the nasal airway from increasing in length infinitely as a straight tube. We thus hypothesized that these ethmoid olfactory channels function as parallel coiled chromatograph channels, and further showed that the theoretical plate number, a widely-used indicator of gas chromatograph efficiency, is more than 100 times higher in the cat nose than an “amphibian-like” straight channel fitting the similar skull space, at restful breathing state. The parallel feature also reduces airflow speed within each coil, which is critical to achieve the high plate number, while feeding collectively from the high-speed dorsal medial stream so that total odor sampling speed is not sacrificed. The occurrence of ethmoid turbinates is an important step in the evolution of mammalian species that correlates to their expansive olfactory function and brain development. Our findings reveal novel mechanisms on how such structure may facilitate better olfactory performance, furthering our understanding of the successful adaptation of mammalian species, including F. catus, a popular pet, to diverse environments. The evolutionary occurrence of convoluted ethmoid turbinate structures in mammalian nose, remarkably resembles a different sensory organ, the snail-like coiled cochlea that is also unique to mammals. In birds and other non-mammalian vertebrates, the inner hearing organ, despite being called “cochlea”, is instead a blind-ended tube. While the evolution of mammalian cochlea enhances our auditory frequency sensitivity and range, the functional benefit of the mammalian olfactory turbinates has only been speculated. Using anatomically-accurate computational models, we revealed that convoluted turbinate structures in the domestic cat, as a model, may function as a parallel coiled chromatograph to significantly increase odor delivery speed and chromatography efficiency: > 100 times higher, compared to an “amphibian-like” straight nasal channel fitting the same skull space.
登录
查看更多内容
影响因子：
1.8
作者：
ETTRE, LS
通讯作者：
ETTRE, LS
影响因子：
3.9
作者：
Craven, Brent A.;Paterson, Eric G.;Settles, Gary S.
通讯作者：
Settles, Gary S.
影响因子：
7.4
作者：
GOLAY, MJE
通讯作者：
GOLAY, MJE
影响因子：
1.3
作者：
ISHII, D;TAKEUCHI, T
通讯作者：
TAKEUCHI, T
影响因子：
5.4
作者：
Koeppl, Christine;Manley, Geoffrey A.
通讯作者：
Manley, Geoffrey A.