Klimaschewski L, Grohmann I, Heym C
Institute of Anatomy and Cell Biology, University of Heidelberg, Germany.
Neuroscience. 1996 May;72(1):265-72. doi: 10.1016/0306-4522(95)00551-x.
The expression of the neuropeptides galanin and vasoactive intestinal peptide (VIP) is increased in subpopulations of sympathetic neurons after axotomy of the rat superior cervical ganglion. We investigated whether postganglionic neurons innervating different targets show a prevalence for any of the two peptides in response to carotid nerve lesion. Before the respective postganglionic axons were crushed close to the ganglion, postganglionic neurons projecting either to the iris (through the internal carotid nerve) or to the submandibular gland (through both carotid branches) were identified by the retrograde tracer Fast Blue. Galanin and VIP immunoreactivities were demonstrated two and 30 days after crush and after successful regeneration of the lesioned neurons (60 days). In control ganglia, both peptides were detected in a few gland- but not in iris-projecting neurons. However, two days after crush of the respective carotid nerves, 14% of neurons within the iris and 46% within the gland population were immunoreactive for galanin. The percentage of neurons immunoreactive for VIP was significantly lower in both populations: only 3.5% of neurons projecting to the iris and 23% of the gland-projecting neuron population exhibited this peptide. After 30 days, the percentage of galanin- and VIP-positive neurons projecting to the submandibular gland was reduced (24% and 5.7%, respectively), whereas the proportion of galanin-immunoreactive neurons further increased within the iris population (55%), indicating that some neurons express galanin at later stages after the lesion. At 60 days after the crush, the percentage of galanin- or VIP-immunoreactive neurons had decreased to control levels within those neuron populations that re-innervated the iris or submandibular gland, although the total number of neurons exhibiting galanin or VIP was still increased within the ganglion, suggesting that re-establishment of target contact may play a role in down-regulation of both peptides.
大鼠颈上神经节轴突切断后，交感神经元亚群中神经肽甘丙肽和血管活性肠肽（VIP）的表达增加。我们研究了支配不同靶标的节后神经元在颈动脉神经损伤后是否对这两种肽中的任何一种有表达优势。在将各自的节后轴突在靠近神经节处压碎之前，通过逆行示踪剂快蓝鉴定出投射到虹膜（通过颈内神经）或下颌下腺（通过两个颈动脉分支）的节后神经元。在压碎后两天、30天以及受损神经元成功再生后（60天），检测甘丙肽和VIP免疫反应性。在对照神经节中，两种肽仅在少数投射到腺体的神经元中检测到，而在投射到虹膜的神经元中未检测到。然而，在各自的颈动脉神经压碎两天后，虹膜内14%的神经元和腺体群体内46%的神经元对甘丙肽呈免疫反应性。在这两个群体中，对VIP呈免疫反应性的神经元百分比显著更低：投射到虹膜的神经元中只有3.5%以及投射到腺体的神经元群体中有23%表现出这种肽。30天后，投射到下颌下腺的甘丙肽和VIP阳性神经元百分比降低（分别为24%和5.7%），而甘丙肽免疫反应性神经元在虹膜群体中的比例进一步增加（55%），表明一些神经元在损伤后的后期阶段表达甘丙肽。在压碎60天后，在重新支配虹膜或下颌下腺的神经元群体中，甘丙肽或VIP免疫反应性神经元的百分比已降至对照水平，尽管神经节内显示甘丙肽或VIP的神经元总数仍然增加，这表明靶标接触的重新建立可能在这两种肽的下调中起作用。
