Effects of spinal lesions on substance P levels in the rat sympathetic preganglionic cell column: evidence for local spinal regulation.
Effects of spinal lesions on substance P levels in the rat sympathetic preganglionic cell column: evidence for local spinal regulation.
复制标题
脊柱病变对大鼠交感神经节前细胞柱 P 物质水平的影响：局部脊柱调节的证据。
DOI：
10.1016/0306-4522(84)90300-2
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发表时间：
1984
期刊：
影响因子：
3.3
通讯作者：
Cabot,JB
中科院分区：
文献类型：
--
作者：
Davis,BM;Krause,JE;McKelvy,JF;Cabot,JB
在光镜和电镜研究中，P物质定位于交感节前神经元的神经鞘。最近的两份报告表明，大鼠中间外侧细胞柱中的大部分P物质包含在球脊髓轴突的突触末端。然而，在我们实验室以前的研究表明，存在的主要P物质脊髓交感节前神经元回路的鸽子。本研究采用放射免疫分析和免疫组织化学方法，以评估球脊髓和椎管内P物质神经元的相对贡献的中间外侧细胞柱的P物质含量的各种脊髓损伤后，在大鼠中间外侧细胞柱的P物质水平。从这些实验的结果支持存在的球脊髓和脊髓内的P物质含有的预测到大鼠中间外侧细胞柱。此外，结合高效液相色谱和放射免疫分析法的脊髓P物质样免疫反应的表征，发现P物质在大鼠中间外侧细胞柱是无法区分的合成P物质。横断胸髓后，P物质免疫反应染色仍然明显的中间外侧细胞柱尾侧的病变。这些P物质阳性纤维上布满钮扣样的分泌物，表现正常。高位颈椎半切后，P物质的消耗（放射免疫测定法测量）是双边和平等的中间外侧细胞柱：25%，消耗后7天和35%消耗后14天。然而，在颈部低位和/或胸部中段被半切的大鼠，中间外侧细胞柱中的P物质含量正常或升高。由于P物质在完全横切后仍保留在中间外侧细胞柱中，因此P物质脊髓-交感神经节前神经元回路一定存在。此外，高位颈椎半切术后P物质的耗竭提示存在一条含P物质的双侧延髓脊髓通路通往中间外侧细胞柱。观察到P物质水平正常或升高后，下颈椎病变提出的可能性，脊髓内的P物质神经元可以补偿的P物质在脊髓中的损失。脊柱内P物质神经元的发芽或改变P物质代谢和/或释放可能是原因，这表明维持中间外侧细胞柱内P物质含量的重要稳态机制。
Substance P has been localized to the neuropil of sympathetic preganglionic neurons in light and electron microscopic studies. Two recent reports have suggested that the majority of substance P in the rat intermediolateral cell column was contained in synaptic terminals of bulbospinal axons. However, previous investigations in our laboratory indicated the presence of major substance P spinal-sympathetic preganglionic neuron circuitry in pigeon. The present study used radioimmunoassay and immunohistochemistry to examine substance P levels in rat intermediolateral cell column following various spinal lesions in order to assess the relative contributions of bulbospinal and intraspinal substance P neurons to the substance P content of the intermediolateral cell column. The results from these experiments support the existence of both bulbospinal and intraspinal substance P-containing projections to the rat intermediolateral cell column. In addition, characterization of spinal cord substance P-like immunoreactivity by combined high performance liquid chromatography and radioimmunoassay, revealed that substance P in rat intermediolateral cell column was indistinguishable from synthetic substance P.Following transection of thoracic spinal cord, substance P-immunoreactive staining was still evident in the intermediolateral cell column caudal to the lesion. These substance P-positive fibers were studded with bouton-like swellings and appeared normal. Following high cervical hemisection, depletion of substance P (radioimmunoassay measurements) was bilateral and equal in the intermediolateral cell column: 25%, depletion was observed after 7 days and 35% depletion after 14 days. However, rats which were hemisected at low cervical and/or mid-thoracic levels contained normal or elevated amounts of substance P in the intermediolateral cell column.Since substance P remains in the intermediolateral cell column following total transection, substance P spinal-sympathetic preganglionic neuron circuitry must exist. Additionally, depletion of substance P following high cervical hemisection suggests the existence of a substance P-containing, bilateral bulbospinal pathway to the intermediolateral cell column. The observation that substance P levels were normal or elevated following low cervical lesions raises the possibility that intraspinal substance P neurons can compensate for loss of substance P in the spinal cord. Sprouting or altered substance P metabolism and/or release by intraspinal substance P neurons could be responsible, suggesting an important homeostatic mechanism for maintaining substance P content within the intermediolateral cell column.