Yasui Y, Nakano K, Mizuno N
Department of Anatomy (1st Division), Mie University School of Medicine, Japan.
Exp Brain Res. 1992;90(3):508-18. doi: 10.1007/BF00230933.
In the course of our study on the neuronal connections of the subparafascicular nucleus (SPF) in the rat, descending projections from the SPF to the lower brain stem were examined by using the anterograde tracer PHA-L (Phaseolus vulgaris leukoagglutinin) and retrograde tracer WGA-HRP (horseradish peroxidase conjugated to wheat germ agglutinin). When PHA-L was injected into the magnocellular and/or parvicellular division of the SPF (SPFm and/or SPFp), presumed terminal labeling was seen, bilaterally with an ipsilateral dominance, in the mesencephalic and pontine central gray matter, peripheral shell regions of the inferior colliculus, cuneiform nucleus, and superior olivary complex (mainly in the superior paraolivary nucleus, and additionally in the nuclei of the trapezoid body). A few labeled axon terminals were also seen in the cochlear nuclei bilaterally with a contralateral dominance. In the second set of experiments, WGA-HRP was injected into the inferior colliculus, superior olivary complex, or cochlear nuclei. When WGA-HRP was injected into the peripheral shell regions of the inferior colliculus or the superior olivary complex, many labeled neuronal cell bodies were seen in the SPFm bilaterally with an ipsilateral dominance, and a moderate number of labeled neuronal cell bodies were observed in the SPFp (lateral SPF) bilaterally with an ipsilateral dominance. When WGA-HRP was injected into the cochlear nuclei, a moderate number of labeled neuronal cell bodies were observed in the SPFm and SPFp bilaterally with a contralateral dominance. The results indicate that the SPFm and SPFp (lateral SPF) of the rat send a considerable number of projection fibers to the lower brain stem. The target regions of these projection fibers include the auditory relay nuclei, such as the inferior colliculus, superior olivary complex, and cochlear nuclei.
在我们对大鼠束旁下核（SPF）神经元连接的研究过程中，使用顺行示踪剂PHA-L（菜豆白细胞凝集素）和逆行示踪剂WGA-HRP（与小麦胚凝集素结合的辣根过氧化物酶）检查了从SPF到低位脑干的下行投射。当将PHA-L注入SPF的大细胞和/或小细胞部分（SPFm和/或SPFp）时，在中脑和脑桥中央灰质、下丘外周壳区、楔状核和上橄榄复合体（主要在上橄榄旁核，另外在斜方体核）中可见双侧推测的终末标记，且同侧占优势。双侧耳蜗核中也可见少数标记的轴突终末，对侧占优势。在第二组实验中，将WGA-HRP注入下丘、上橄榄复合体或耳蜗核。当将WGA-HRP注入下丘外周壳区或上橄榄复合体时，双侧SPFm中可见许多标记的神经元细胞体，同侧占优势，双侧SPFp（外侧SPF）中可见中等数量的标记神经元细胞体，同侧占优势。当将WGA-HRP注入耳蜗核时，双侧SPFm和SPFp中可见中等数量的标记神经元细胞体，对侧占优势。结果表明，大鼠的SPFm和SPFp（外侧SPF）向低位脑干发出大量投射纤维。这些投射纤维的靶区包括听觉中继核，如下丘、上橄榄复合体和耳蜗核。
