Altman J, Bayer S A
J Comp Neurol. 1980 Dec 15;194(4):877-904. doi: 10.1002/cne.901940410.
Groups of pregnant rats were injected with two successive daily doses of 3H-thymidine from gestational days 12 and 13 (E12 + 13) until the day before parturition (E21 + 22). In adult progeny of the injected rats the proportion of neurons generated on specific embryonic days was determined quantitatively in the vestibular and auditory nuclei of the upper medulla. In the vestibular nuclei, neurons are generated between days E11 and E15 in an overlapping sequential order, yielding a lateral-to-medial and a rostral-to-caudal internuclear gradient. In the lateral vestibular nucleus peak production time is day E12; in the superior nucleus, E13; in the inferior nucleus, E13 and E14; and in the medial nucleus, E14. The early generation of neurons of the lateral vestibular nucleus may reflect the early differentiation of the circuit from the gravity receptors (utricle) to neurons of the spinal cord controlling postural balance. The later production of neurons of the superior vestibular nucleus may reflect the subsequent differentiation of the circuit from the rotational receptors (semicircular canals) to the neurons of the brain stem controlling eye movements. The generation time of neurons of the nucleus prepositus hypoglossi overlaps with that of the medial vestibular nucleus. The neurons of the anteroventral and posteroventral cochlear nuclei are produced from days E13 to E17, with no temporal differences between the two nuclei. The neurons of the dorsal cochlear nucleus are generated over a very long time span, beginning on day E12 and extending into the postnatal period. There is a sequence in the production of neurons forming the different layers of the dorsal cochlear nucleus in the following order: pyramidal cells, cells of the inner layer, cells of the outer layer and, finally, cells of the granular layer. There is also a sequential production of neurons in four nuclei of the superior olivary complex. In the lateral trapezoid nucleus peak production time is day E12; in the medial superior olivary nucleus, day E13; in the medial trapezoid nucleus, day E15; and in the lateral superior olivary nucleus, day E16. This order yields a medial-to-lateral gradient in the dorsal aspect of the superior olivary complex, and a lateral-to-medial gradient ventrally. These mirror-image gradients were also seen intranuclearly in the lateral superior olivary nucleus and the medial trapezoid nucleus. The cytogenetic gradients could not be related to tonotopic representation; however, they could be related to the lateral location of ipsilateral cochlear nucleus input to the lateral superior olivary nucleus and the medial location of the contralateral cochlear nucleus input to the medial trapezoid nucleus.
将怀孕大鼠分为几组，从妊娠第12天和第13天（E12 + 13）开始，每天连续注射两次3H-胸腺嘧啶，直至分娩前一天（E21 + 22）。在注射大鼠的成年子代中，定量测定上延髓前庭和听觉核中在特定胚胎期产生的神经元比例。在前庭核中，神经元在E11至E15天之间以重叠的顺序产生，形成从外侧到内侧以及从嘴侧到尾侧的核间梯度。在外侧前庭核中，峰值产生时间是E12天；在上核中，是E13天；在下核中，是E13和E14天；在内侧核中，是E14天。外侧前庭核神经元的早期产生可能反映了从重力感受器（椭圆囊）到控制姿势平衡的脊髓神经元的回路的早期分化。前庭上核神经元的后期产生可能反映了从旋转感受器（半规管）到控制眼球运动的脑干神经元的回路的后续分化。舌下前置核神经元的产生时间与内侧前庭核的产生时间重叠。前腹侧和后腹侧耳蜗核的神经元在E13至E17天产生，两个核之间没有时间差异。背侧耳蜗核的神经元在很长的时间跨度内产生，从E12天开始并延伸到出生后时期。形成背侧耳蜗核不同层的神经元按以下顺序产生：锥体细胞、内层细胞、外层细胞，最后是颗粒层细胞。上橄榄复合体的四个核中也有神经元的顺序产生。在外侧梯形核中，峰值产生时间是E12天；在内侧上橄榄核中，是E13天；在内侧梯形核中，是E15天；在外侧上橄榄核中，是E16天。这种顺序在上橄榄复合体的背侧形成从内侧到外侧的梯度，在腹侧形成从外侧到内侧的梯度。这些镜像梯度也见于外侧上橄榄核和内侧梯形核的核内。细胞遗传学梯度与音频定位无关；然而，它们可能与同侧耳蜗核输入到外侧上橄榄核的外侧位置以及对侧耳蜗核输入到内侧梯形核的内侧位置有关。
