Alibardi L
Department of Biology, University of Bologna, Italy.
J Submicrosc Cytol Pathol. 2000 Oct;32(4):555-66.
The type of synaptic terminals from the cochlear nucleus and inferior colliculus that terminate in the contralateral ventral cochlear nucleus are not known. These terminals were studied with the electron microscope and immunogold after injection of wheat germ agglutinin conjugated to horseradish peroxidase into the inferior colliculus or into the cochlear nucleus. The tracer anterogradely labelled boutons onto the main neurons of the contralateral ventral cochlear nucleus. Most of these cells (95%) were glycine immuno-negative and represent excitatory neurons. After injection of the tracer into the contralateral inferior colliculus few anterogradely labelled boutons were seen on spherical and multipolar cells of type II in the anteroventral cochlear nucleus. Rare labelled boutons were present on multipolar cells of type I and II, globular neurons and octopus cells in the posteroventral cochlear nucleus. After injection into the contralateral dorsal and ventral cochlear nucleus labelled boutons were seen more frequently than after injection into the inferior colliculus. These terminals contacted most of large neurons, especially multipolar cells of type II and less frequently of type I. Also globular and spherical cells were contacted by commissural terminals. Octopus cells received less frequently putative commissural terminals. Most boutons contained pleomorphic vesicles and stored GABA. A lower number of boutons with pleomorphic and flat vesicles contained glycine and sometimes GABA, both inhibitory neurotransmitters. Few boutons containing round vesicles were immuno-negative for both glycine and GABA, and were considered putative commissural excitatory terminals. The latter often contacted glycinergic neurons of type II so that also these terminals might elicit an inhibition with at least a disynaptic mechanism after contralateral stimulation.
终止于对侧蜗腹侧核的来自蜗神经核和下丘的突触终末类型尚不清楚。在将与辣根过氧化物酶结合的小麦胚凝集素注入下丘或蜗神经核后，用电子显微镜和免疫金对这些终末进行了研究。示踪剂顺行标记了对侧蜗腹侧核主神经元上的终扣。这些细胞中的大多数（95%）为甘氨酸免疫阴性，代表兴奋性神经元。将示踪剂注入对侧下丘后，在前庭蜗神经核II型的球形和多极细胞上可见少量顺行标记的终扣。在蜗后腹侧核的I型和II型多极细胞、球状神经元和章鱼形细胞上存在罕见的标记终扣。注入对侧背侧和腹侧蜗神经核后，标记终扣比注入下丘后更常见。这些终末与大多数大神经元接触，尤其是II型多极细胞，较少与I型多极细胞接触。连合终末也与球状和球形细胞接触。章鱼形细胞较少接受假定的连合终末。大多数终扣含有多形性囊泡并储存GABA。少数含有多形性和平扁囊泡的终扣含有甘氨酸，有时还含有GABA，二者均为抑制性神经递质。少数含有圆形囊泡的终扣对甘氨酸和GABA均呈免疫阴性，被认为是假定的连合兴奋性终末。后者常与II型甘氨酸能神经元接触，因此这些终末在对侧刺激后也可能至少通过双突触机制引发抑制。
