Bhatnagar K P, Kallen F C
Acta Anat (Basel). 1975;91(2):272-82. doi: 10.1159/000144389.
The nasal epithelia of two species of bats were quantified with respect to relative surface areas and olfactory epithelial volumes. In the macrosmatic Aribeus jamaicensis 55.9% of the nasal cavity surface was covered by olfactory epithelium (232.4 mm2), in contrast to only 28.9% in the microsmatic Myotis lucifugus (36.4 mm2). The roles of the various nasal epithelia have been discussed as they may relate to olfaction, respiration and echolocation. In the olfactory bulbs of both species, the estimated concentration of mitral cells approximated at 2,500/mm2 compared to an olfactory nerve concentration of 5/mm2. In Artibeus, calculated total volume of olfactory epithelium was on the order of 16 times greater than in Myotis, and Artibeus' olfactory bulb diameter was twice as great. These findings, together with previously published surface, volume and physiological relationships, suggest a developmental design mechanism for an olfactory bulb in which the number of olfactory receptors increases some 450-fold above an initially established ratio of 2:1 between receptors and mitral cells. Key governing factors could be requisite mechanical rigidity of the cribriform plate of the ethmoid bone and response thresholds of higher brain centers.
对两种蝙蝠的鼻上皮进行了相对表面积和嗅上皮体积的量化研究。在嗅觉灵敏的牙买加短尾叶鼻蝠中，鼻腔表面的55.9%被嗅上皮覆盖（232.4平方毫米），相比之下，嗅觉不灵敏的大鼠耳蝠中只有28.9%被嗅上皮覆盖（36.4平方毫米）。讨论了各种鼻上皮的作用，因为它们可能与嗅觉、呼吸和回声定位有关。在这两种蝙蝠的嗅球中，估计的二尖瓣细胞浓度约为2500个/平方毫米，而嗅神经浓度为5个/平方毫米。在短尾叶鼻蝠中，计算得出的嗅上皮总体积约为大鼠耳蝠的16倍，且短尾叶鼻蝠的嗅球直径是大鼠耳蝠的两倍。这些发现，连同先前发表的表面、体积和生理关系，提示了一种嗅球的发育设计机制，即嗅觉受体的数量比最初建立的受体与二尖瓣细胞2:1的比例增加约450倍。关键的控制因素可能是筛骨筛板所需的机械刚性和高级脑中枢的反应阈值。
