Coleman J R, Clerici W J
J Comp Neurol. 1987 Aug 8;262(2):215-26. doi: 10.1002/cne.902620204.
Brainstem and forebrain projections to major subdivisions of the rat inferior colliculus were studied by using retrograde and anterograde transport of horseradish peroxidase. Retrograde label from injection into the external cortex of the inferior colliculus appears bilaterally in cells of the inferior colliculus, as well as in other brainstem auditory groups including the ipsilateral dorsal nucleus of the lateral lemniscus and contralateral dorsal cochlear nucleus. The external cortex is the only collicular subdivision where an injection labels cells in the contralateral cuneate nucleus, gracile nucleus, and spinal trigeminal nucleus. Other projecting cells to the external cortex are found in the lateral nucleus of substantia nigra, the parabrachial region, the deep superior colliculus, the midbrain central gray, the periventricular nucleus, and area 39 of auditory cortex. Injection of the dorsal cortex of inferior colliculus heavily labels pyramidal cells of areas 41, 20, and 36 of the ipsilateral neocortex. Anterograde label from a large injection of auditory cortex is densely distributed in the dorsal cortex, lesser so in the external cortex, and only slightly in the central nucleus. Labelled cells appear in the central nucleus, dorsal cortex, and external cortex, primarily ipsilaterally, following dorsal cortex injection. Relatively few cells from other brainstem auditory groups show projections to the dorsal cortex. Injection of the central nucleus of the inferior colliculus results in robust labelling of nuclei of the ascending auditory pathway including the anteroventral, posteroventral, and dorsal cochlear nuclei (mainly contralaterally), and bilaterally the lateral superior olive, lateral nucleus of the trapezoid body, dorsal nucleus of the lateral lemniscus, and the central nucleus, dorsal cortex, and external cortex of the colliculus. The medial superior olive, superior paraolivary nucleus, and ventral nucleus of the trapezoid body essentially show ipsilateral projections to the central nucleus. The differential distribution of afferents to the inferior colliculus provides a substrate for functional parcellation of collicular subdivisions.
利用辣根过氧化物酶的逆行和顺行运输，研究了大鼠下丘主要亚区的脑干和前脑投射。向下丘外侧皮质注射后的逆行标记，双侧出现在下丘的细胞中，以及包括同侧外侧丘系背核和对侧蜗背侧核在内的其他脑干听觉组中。外侧皮质是下丘唯一的一个亚区，在此注射会标记对侧楔束核、薄束核和三叉神经脊束核中的细胞。向外侧皮质投射的其他细胞见于黑质外侧核、臂旁区、上丘深部、中脑中央灰质、室周核和听觉皮质39区。向下丘背侧皮质注射会大量标记同侧新皮质41、20和36区的锥体细胞。大量注射听觉皮质后的顺行标记密集分布于背侧皮质，外侧皮质较少，中央核仅有少量。向下丘背侧皮质注射后，标记细胞主要同侧出现在中央核、背侧皮质和外侧皮质。来自其他脑干听觉组的细胞向背侧皮质投射的相对较少。向下丘中央核注射会使包括前腹侧、后腹侧和蜗背侧核（主要是对侧）在内的上行听觉通路核，以及双侧的外侧上橄榄核、斜方体外侧核、外侧丘系背核，以及下丘的中央核、背侧皮质和外侧皮质出现强烈标记。内侧上橄榄核、上橄榄旁核和斜方体腹侧核主要同侧投射至中央核。下丘传入纤维的差异分布为下丘亚区的功能划分提供了基础。
