Fech Tatiana, Calderón-Garcidueñas Lilian, Kulesza Randy J
Department of Anatomy, Lake Erie College of Osteopathic Medicine, Erie, PA, USA.
The University of Montana, Missouola, MT, USA; Universidad del Valle de Mexico, Mexico.
Hear Res. 2017 Aug;351:130-140. doi: 10.1016/j.heares.2017.06.010. Epub 2017 Jun 15.
The superior olivary complex (SOC) is a collection of brainstem auditory nuclei which play essential roles in the localization of sound sources, temporal coding of vocalizations and descending modulation of the cochlea. Notwithstanding, the SOC nuclei vary considerably between species in accordance with the auditory needs of the animal. The canine SOC was subjected to anatomical and physiological examination nearly 50 years ago and was then virtually forgotten. Herein, we aimed to characterize the nuclei of the canine SOC using quantitative morphometrics, estimation of neuronal number, histochemistry for perineuronal nets and immunofluorescence for the calcium binding proteins calbindin and calretinin. We found the principal nuclei to be extremely well developed: the lateral superior olive (LSO) contained over 20,000 neurons and the medial superior olive (MSO) contained over 15,000 neurons. In nearly all non-chiropterian terrestrial mammals, the MSO exists as a thin, vertical column of neurons. The canine MSO was folded into a U-shaped contour and had associated with the ventromedial tip a small, round collection of neurons we termed the tail nucleus of the MSO. Further, we found evidence within the LSO, MSO and medial nucleus of the trapezoid body (MNTB) for significant morphological variations along the mediolateral or rostrocaudal axes. Finally, the majority of MNTB neurons were calbindin-immunopositive and associated with calretinin-immunopositive calyceal terminals. Together, these observations suggest the canine SOC complies with the basic plan of the mammalian SOC but possesses a number of unique anatomical features.
上橄榄复合体（SOC）是脑干听觉核团的集合，在声源定位、发声的时间编码以及耳蜗的下行调制中发挥着重要作用。尽管如此，SOC核团在不同物种之间因动物的听觉需求而有很大差异。犬类的SOC在近50年前就接受了解剖学和生理学检查，之后几乎被遗忘。在此，我们旨在通过定量形态计量学、神经元数量估计、神经周网的组织化学以及钙结合蛋白钙结合蛋白和钙视网膜蛋白的免疫荧光来表征犬类SOC的核团。我们发现主要核团发育得非常好：外侧上橄榄核（LSO）包含超过20,000个神经元，内侧上橄榄核（MSO）包含超过15,000个神经元。在几乎所有非翼手目陆生哺乳动物中，MSO以细长的垂直神经元柱形式存在。犬类的MSO折叠成U形轮廓，并在腹内侧尖端与一小群圆形神经元相连，我们将其称为MSO的尾核。此外，我们在LSO、MSO和梯形体内侧核（MNTB）中发现了沿内外侧或头尾轴存在显著形态变化的证据。最后，大多数MNTB神经元钙结合蛋白免疫阳性，并与钙视网膜蛋白免疫阳性的杯状终末相关。这些观察结果共同表明，犬类SOC符合哺乳动物SOC的基本结构，但具有一些独特的解剖学特征。
