Smith Philip H, Massie Ann, Joris Philip X
Department of Anatomy, University of Wisconsin, Medical School-Madison, 1300 University Ave., Madison, Wisconsin 53706, USA.
J Comp Neurol. 2005 Feb 21;482(4):349-71. doi: 10.1002/cne.20407.
The mammalian cochlear nucleus (CN) has been a model structure to study the relationship between physiological and morphological cell classes. Several issues remain, in particular with regard to the projection patterns and physiology of neurons that exit the CN dorsally via the dorsal (DAS), intermediate (IAS), and commissural stria. We studied these neurons physiologically and anatomically using the intra-axonal labeling method. Multipolar cells with onset chopper (O(C)) responses innervated the ipsilateral ventral and dorsal CN before exiting the CN via the commissural stria. Upon reaching the midline they turned caudally to innervate the opposite CN. No collaterals were seen innervating any olivary complex nuclei. Octopus cells typically showed onset responses with little or no sustained activity. The main axon used the IAS and followed one of two routes occasionally giving off olivary complex collaterals on their way to the contralateral ventral nucleus of the lateral lemniscus (VNLL). Here they can have elaborate terminal arbors that surround VNLL cells. Fusiform and giant cells have overlapping but not identical physiology. Fusiform but not giant cells typically show pauser or buildup responses. Axons of both cells exit via the DAS and take the same course to reach the contralateral IC without giving off any collaterals en route.
哺乳动物的耳蜗核(CN)一直是研究生理和形态细胞类别之间关系的模型结构。仍有几个问题存在,特别是关于通过背侧(DAS)、中间(IAS)和连合纹从背侧离开CN的神经元的投射模式和生理学。我们使用轴突内标记法对这些神经元进行了生理和解剖学研究。具有起始斩波器(O(C))反应的多极细胞在通过连合纹离开CN之前支配同侧腹侧和背侧CN。到达中线后,它们转向尾侧支配对侧CN。未见侧支支配任何橄榄复合体核。章鱼细胞通常表现出起始反应,几乎没有或没有持续活动。主要轴突使用IAS,并沿着两条路径之一,偶尔在其通向对侧外侧丘系腹侧核(VNLL)的途中发出橄榄复合体侧支。在这里,它们可以有围绕VNLL细胞的复杂终末树突。梭形细胞和巨细胞具有重叠但不完全相同的生理学特征。梭形细胞而非巨细胞通常表现出暂停或增强反应。两种细胞的轴突都通过DAS离开,并沿着相同的路径到达对侧IC,途中不发出任何侧支。