Azizi S A, Mihailoff G A, Burne R A, Woodward D J
J Comp Neurol. 1981 Apr 20;197(4):543-8. doi: 10.1002/cne.901970402.
This study was undertaken to determine the origin of projections from the basilar pontine nuclei (BPN) and nucleus reticularis tegmentis pontis (NRTP) to the posterior vermal lobules VI-IX of the rat cerebellum. We describe the topographical organization of this component of the pontocerebellar projection, and the congruence of the cells of origin in the basilar pons with some of the major pontine afferent systems including the corticopontine and tectopontine projections. Horseradish peroxidase (HRP) was injected into the midline cerebellar vermal zones of Long-Evans hooded rats. The more sensitive chromogens, tetramethyl benzidine and benzidine dihydrochloride, were used to reveal the location of labeled neurons. With injections located near the midline, groups of labeled cells were observed bilaterally within the BPN. The basic trend of the projections noted was: lobule VIa receives a nonfocal projection from nearly all subdivisions of the BPN throughout its rostrocaudal extent, as well as a substantial input from NRTP. Lobules VIb-c receive input from NRTP, the rostral pons, and from the ventral, lateral, and medial groups of cells in the middle BPN project to lobule VII, in addition to projections from limited groups of cells in the rostral BPN. Lobule VIII receives afferents from the caudal aspect of the pontine gray. Lobules IXa-receive afferents from the medial and peduncular groups in the midline BPN, whereas lobule IXc receives inputs from a medial group and a small lateral cluster of cells in the caudal aspect of the BPN. Pontine neurons projecting to the posterior vermis originate from areas which appear to receive descending inputs from visual, auditory, and somatosensory regions of the cerebral cortex. However, a large number of pontine and NRTP neurons projecting to lobules VI and VII are located within the terminal fields of tectal neurons, perhaps indicating a stronger input from the tectum rather than visual and auditory cerebral cortical regions.
本研究旨在确定大鼠脑桥基底部核团（BPN）和脑桥被盖网状核（NRTP）向小脑蚓部后叶VI - IX的投射起源。我们描述了脑桥小脑投射这一组成部分的拓扑组织，以及脑桥基底部起源细胞与一些主要脑桥传入系统（包括皮质脑桥和顶盖脑桥投射）的一致性。将辣根过氧化物酶（HRP）注入长 - 伊文斯帽状大鼠的小脑蚓部中线区域。使用更灵敏的显色剂四甲基联苯胺和盐酸联苯胺来揭示标记神经元的位置。在靠近中线处注射时，双侧在BPN内观察到成群的标记细胞。所观察到的投射基本趋势是：小叶VIa在其整个前后范围内几乎从BPN的所有亚区接受非局灶性投射，以及来自NRTP的大量输入。小叶VIb - c接受来自NRTP、脑桥前部以及脑桥中部腹侧、外侧和内侧细胞群向小叶VII的投射，此外还有来自脑桥前部有限细胞群的投射。小叶VIII接受来自脑桥灰质尾部的传入纤维。小叶IXa接受来自中线BPN内侧和脚周组的传入纤维，而小叶IXc接受来自BPN尾部内侧组和一小群外侧细胞的输入。投射到小脑蚓部后部的脑桥神经元起源于似乎接受来自大脑皮质视觉、听觉和躯体感觉区域下行输入的区域。然而，大量投射到小叶VI和VII的脑桥和NRTP神经元位于顶盖神经元的终末场内，这可能表明来自顶盖而非视觉和听觉大脑皮质区域的输入更强。
