Davis B M, Cabot J B
J Neurosci. 1984 Aug;4(8):2145-59. doi: 10.1523/JNEUROSCI.04-08-02145.1984.
The origin of substance P-like immunoreactivity (SPLI) in the neuropil of sympathetic preganglionic neurons (SPNs) was investigated in pigeon (Columba livia). Previous investigators had suggested that a major SPLI-containing projection to SPNs arose from caudal brainstem (Johansson, O., T. Hokfelt, B. Pernow, S. L. Jeffcoate, N. White, H. W. M. Steinbusch, A. A. J. Verhofstad, P. C. Emson, and E. Spindel (1981) Neuroscience 6: 1857-1881; Gilbert, R. F. T., P.C. Emson, S. P. Hunt, G. W. Bennett, C. A. Marsden, B. E. B. Sandberg, H. W. M. Steinbusch, and A. A. J. Verhofstad (1982) Neuroscience 7: 69-87; Helke, C. J. J. J. Neil, V. J. Massari, and A. D. Loewy (1982) Brain Res. 243: 147-152) and, furthermore, that the bulbospinal fibers and terminals in the SPN neuropil which contained SPLI also contained serotonin-like immunoreactivity (5-HTLI) (Johansson, O., T. Hokfelt, B. Pernow, S. L. Jeffcoate, N. White, H. W. M. Steinbusch, A. A. J. Verhofstad, P. C. Emson, and E. Spindel (1981) Neuroscience 6: 1857-1881; Gilbert, R. F. T., P.C. Emson, S. P. Hunt, G. W. Bennett, C.A. Marsden, B. E. B. Sandberg, H. W. M. Steinbusch, and A. A. J. Verhofstad (1982) Neuroscience 7: 69-87). In the present study, various spinal lesions were made and the SPLI and 5-HTLI content of thoracic spinal cord was examined using immunohistochemistry. Interruption of descending bulbospinal fibers by cervical hemisection had no demonstrable effect on SPLI in the SPN neuropil, while 5-HTLI was almost totally depleted in the half of the spinal gray (including the SPN cell column) ipsilateral to the hemisection. Following a complete thoracic transection, SPLI was only depleted 2 to 3 mm rostral and caudal to the lesion, while normal SPLI staining was present in the remainder of the spinal cord. 5-HTLI was totally depleted caudal to a thoracic transection. Dorsal rhizotomy of three to six sequential spinal segments significantly depleted SPLI in the dorsal horn but had no effect on SPLI in the region of SPNs. Major depletion of SPLI within the SPN cell column was only seen when portions of thoracic spinal cord were isolated by complete transections or unilateral hemisections. Finally, evidence was found for intraspinal SPLI-containing fiber systems. These results demonstrate that the majority of SPLI in the SPN cell column in the pigeon is probably of intraspinal origin. The data also confirm that 5-HTLI is contained in axons and terminals arising from cell bodies of supraspinal origin.
在鸽子（Columba livia）中，对交感神经节前神经元（SPN）神经纤维网中P物质样免疫反应性（SPLI）的起源进行了研究。先前的研究人员曾提出，向SPN的一个主要含SPLI投射源自延髓尾端（Johansson, O., T. Hokfelt, B. Pernow, S. L. Jeffcoate, N. White, H. W. M. Steinbusch, A. A. J. Verhofstad, P. C. Emson, and E. Spindel (1981) Neuroscience 6: 1857 - 1881; Gilbert, R. F. T., P.C. Emson, S. P. Hunt, G. W. Bennett, C. A. Marsden, B. E. B. Sandberg, H. W. M. Steinbusch, and A. A. J. Verhofstad (1982) Neuroscience 7: 69 - 87; Helke, C. J. J. J. Neil, V. J. Massari, and A. D. Loewy (1982) Brain Res. 243: 147 - 152），此外，SPN神经纤维网中含SPLI的延髓脊髓纤维和终末也含有5-羟色胺样免疫反应性（5-HTLI）（Johansson, O., T. Hokfelt, B. Pernow, S. L. Jeffcoate, N. White, H. W. M. Steinbusch, A. A. J. Verhofstad, P. C. Emson, and E. Spindel (1981) Neuroscience 6: 1857 - 1881; Gilbert, R. F. T., P.C. Emson, S. P. Hunt, G. W. Bennett, C.A. Marsden, B. E. B. Sandberg, H. W. M. Steinbusch, and A. A. J. Verhofstad (1982) Neuroscience 7: 69 - 87）。在本研究中，制作了各种脊髓损伤，并使用免疫组织化学方法检测胸段脊髓的SPLI和5-HTLI含量。颈髓半切中断下行的延髓脊髓纤维对SPN神经纤维网中的SPLI没有明显影响，而在半切同侧的脊髓灰质（包括SPN细胞柱）中，5-HTLI几乎完全耗尽。在进行完全的胸段横断后，SPLI仅在损伤部位头端和尾端2至3毫米处减少，而脊髓其余部分的SPLI染色正常。5-HTLI在胸段横断以下完全耗尽。对三到六个连续脊髓节段进行背根切断术可使背角中的SPLI显著减少，但对SPN区域的SPLI没有影响。仅当通过完全横断或单侧半切将部分胸段脊髓分离时，才会在SPN细胞柱内看到SPLI的主要减少。最后，发现了脊髓内含有SPLI的纤维系统的证据。这些结果表明，鸽子SPN细胞柱中的大多数SPLI可能起源于脊髓内。数据还证实，5-HTLI存在于源自脊髓上神经元胞体的轴突和终末中。
