A quantitative light microscopic analysis and ultrastructural description of cholecystokinin-like immunoreactivity in the spinal trigeminal nucleus of the rat.
A quantitative light microscopic analysis and ultrastructural description of cholecystokinin-like immunoreactivity in the spinal trigeminal nucleus of the rat.
复制标题
大鼠三叉神经脊髓核中胆囊收缩素样免疫反应性的定量光学显微镜分析和超微结构描述。
DOI：
10.1016/0306-4522(87)90102-3
复制
发表时间：
1987
期刊：
影响因子：
3.3
通讯作者：
Beitz,AJ
中科院分区：
文献类型：
--
作者：
Clements,JR;Beitz,AJ
三叉神经脊核参与口面部感觉传递。胆囊收缩素八肽已在该核的轴突中被发现，并且似乎在口面部感觉从三叉神经节到三叉神经脊髓核的传递中发挥作用。尽管在光显微镜水平上已报道胆囊收缩素存在于三叉神经脊核内的轴突中，但对于这些胆囊收缩素轴突的突触关系尚不清楚。本研究的目的是定量测定三叉神经脊髓核三个亚核中缩胆囊素样免疫反应细胞体和纤维的体积分数，提供这些亚核内缩胆囊素样免疫反应过程的第一个超微结构描述，并分析三叉神经脊髓脊神经纤维内缩胆囊素样免疫反应过程的突触关系。通过过氧化物酶-抗过氧化物酶方法或过氧化物酶标记的抗生物素蛋白-生物素技术来定位免疫反应性，并通过点计数在光学显微镜水平上进行定量。免疫反应性纤维存在于所有三个亚核中，但免疫反应性轴突的最大体积分数是在尾核 I 和 II 层中获得的。在任何亚核中都没有明显的免疫反应性细胞体。所有三个亚核中的大多数免疫反应谱均在超微结构上被鉴定为轴突末端，其中包含小型和中型无颗粒囊泡以及罕见的大型致密核心囊泡。这些免疫反应末端通常与非免疫反应树突紧密接触，观察到它们与树突形成不对称突触。偶尔观察到免疫反应性末端与尾核 I 和 II 层边界上的大非免疫反应性神经元的细胞体接触。这些结果表明，胆囊收缩素样免疫反应过程存在于整个脊髓三叉神经核中，并且在尾核中显示出与脊髓背角报道相似的分布。免疫反应性轴突与脊髓三叉核神经元的树突和核周发生突触接触。没有观察到轴轴突触。这些发现表明胆囊收缩素在三叉神经脊髓核功能中发挥重要作用。还讨论了胆囊收缩素和 P 物质在三叉神经脊核中可能的共定位以及胆囊收缩素在减弱阿片类药物在三叉神经脊核中的作用中的可能作用。
The spinal trigeminal nucleus is involved in orofacial sensory transmission. Cholecystokinin octapeptide has been identified in axons in this nucleus and appears to play a role in the transmission of orofacial sensation from the trigeminal ganglia to the spinal trigeminal nucleus. Although cholecystokinin has been reported in axonal processes within the spinal trigeminal nucleus at the light microscopic level, nothing is known about the synaptic relationships of these cholecystokinin axons. The goals of this study were to quantitatively determine the volume fraction of cholecystokinin-like immunoreactive cell bodies and fibers in the three subnuclei of the spinal trigeminal nucleus, to provide the first ultrastructural description of cholecystokinin-like immunoreactive processes within these subnuclei and to analyse the synaptic relationships of cholecystokinin-like immunoreactive processes within the spinal trigeminal nucleus neuropil.Cholecystokinin-like immunoreactivity was localized by the peroxidase-antiperoxidase method or the peroxidase labeled, avidin-biotin technique and quantified at the light microscopic level by point counting. Immunoreactive fibers were present in all three subnuclei, but the greatest volume fraction of immunoreactive axons was obtained in laminae I and II of the nucleus caudalis. No immunoreactive cell bodies were evident in any of the subnuclei. The majority of immunoreactive profiles in all three subnuclei were identified ultrastructurally as axon terminals that contained both small and medium sized agranular vesicles and infrequently, large dense core vesicles. These immunoreactive terminals were usually found in close contact with non-immunoreactive dendrites with which they were observed to form asymmetric synapses. Immunoreactive terminals were occasionally observed to contact the cell bodies of large non-immunoreactive neurons on the border of laminae I and II in the nucleus caudalis.These results indicate that cholecystokinin-like immunoreactive processes are present throughout the spinal trigeminal nucleus and in nucleus caudalis show a distribution similar to that reported for the spinal cord dorsal horn. Immunoreactive axons make synaptic contact with both the dendrites and perikarya of spinal trigeminal nucleus neurons. No axoaxonic synapses were observed. These findings suggest that cholecystokinin plays an important role in spinal trigeminal nucleus function. The possible colocalization of cholecystokinin and substance P in the spinal trigeminal nucleus and the possible role of cholecystokinin in attenuating the action of opioids in the spinal trigeminal nucleus are also discussed.